Time to SAS Hawairish's truck

[adamzan]

This is great! I seriously envy your ambition to tackle this project.

[hawairish]

On 2/24/2025 at 10:20 PM, Slartibartfast said:

Congrats on the milestone of working steering! Feels like this thing's getting close.

 

14 hours ago, adamzan said:

This is great! I seriously envy your ambition to tackle this project.

 

Thanks fellas!  Yeah, it's a big push right now and I'm stressing about it a bit.  My next "Brodeo" trip with the guys is coming up early April and we're off to Moab again, so this has to be on the road ASAP, particularly to get it through emissions, registration renewed, and of course, at least one shakedown run...hopefully two.  Current goal is to have it able to roll under power by the end of this weekend, but it won't be streetable quite yet.  I still need to do the bump stop pads, limit straps, steering stabilizer, and a front driveshaft, but I can at least move it out of the garage without those.  More to come soon!

[R50JR]

6 hours ago, hawairish said:

 

 

Thanks fellas!  Yeah, it's a big push right now and I'm stressing about it a bit.  My next "Brodeo" trip with the guys is coming up early April and we're off to Moab again, so this has to be on the road ASAP, particularly to get it through emissions, registration renewed, and of course, at least one shakedown run...hopefully two.  Current goal is to have it able to roll under power by the end of this weekend, but it won't be streetable quite yet.  I still need to do the bump stop pads, limit straps, steering stabilizer, and a front driveshaft, but I can at least move it out of the garage without those.  More to come soon!

No invite!?...joking of course, but I'm actually planning on flying back into town early April. Can't wait to see the finished product!

[hawairish]

Alright, bit of an update...

 

First off, I did not meet my goal of having it rolling by the end of Feb.  Maybe this weekend, we'll see.  Right now, the axle has been removed from the truck for hopefully the last time.  Pulled it off to finish welding the bump stop pads, steering stabilizer mount, whatever touch-ups, and then paint.  To that extent, axle work is DONE!  Will get some pics when it's daylight.

 

The last couple weeks have been super busy.  Almost every day and/or night that I can.  Updates...

 

Finished the air conversion for the sway bar disconnect.  Big thanks again to @TowndawgR50 for making the piston rod and all his support on this project!  Have yet to test it on the truck (my OBA setup has been pulled for re-work) but it's ready to go.

 

 

 

Not sure I showed this previously, but I made it so that I don't have to pull parts from the engine bay to access the strut tower/mount hardware any more.  Now I can just unbolt the upper coilover mount from underneath.  Maybe one day I'll pursue a strut tower brace.

 

 

Finished the brake caliper mounts!  Well...almost.  Still need to powder coat the RH side, but the LH side is done.

 

 

 

 

 

This f$kc!ng pic just reminded me right now that I forgot to grind the knuckle for clearance to install the lower caliper bolt, which I needed to switch out to socket bolts due to the space.  Well, guess that's happening tomorrow and some repainting...

 

...

 

I did have a bit of a setback with the power steering setup.  I was mocking up the steering stabilizer and had the truck running with the wife turning the wheel so I could change for clearances.  *SPLOOSH*  ATF spraying all over.  The aftermath...

 

 

After assessing the failure, I deemed it operator error on two faults:

1. Despite being as gentle as I could to push the braided sheathing back using a small screwdriver per instructions, I must've weakened the PTFE liner enough.
2. I must've pushed the braids too far back with insufficient overlap on the ferrule.

 

 

So, I can tell you that ATF absolutely sucks to clean up.  It is a nasty, nasty chemical.  (And for those wondering, yes, I am using ATF as my power steering fluid...it's what is spec'd.)  That $hit got everywhere.  I cleared the space out and power washed the engine and concrete shortly after this happened and the engine is still dropping ATF in spots...and I only worsened the mess during the repair process.  I can't wait to get the truck out of the garage to really hose it down!

 

Anyway, I ponied up for a proper tool from JEGS that pushes the braid down uniformly and to the correct depth.  I was reluctant to drop $50 initially, but I paid the price and then some for not getting it in the first place.  I pulled all the lines (two; four fittings total) to inspect and redo them.  My original fitting installs were showing a little bit of fatigue that likely would've let to failure again.  I have a little more confidence this time around having used the tool.

 

Here's the new line, shown on the concrete where the spill occurred as indicated by the silhouette where my foam mat was.

 

 

This was the direction the steering stabilizer was heading before the busted line:

 

 

After doing all the other work on steering angles and such, this is basically the only place I had left to mount it.  It hangs about as low as the axle tube, so it's not really eating any more ground clearance, but it will likely be the first thing to be struck.  I tried to keep the brackets simple, and while this piece worked great, the plate came too close to the diff cover for my liking.  I went with a different design that rotates the plate around (the u-bolts have plenty of clearance) and allows me to slide the bracket a couple inches towards the passenger side just in case.  Pics to follow.

 

...

 

I received my front driveshaft!  Ebay special for $300, custom length for my project, intended for "hack-n-tap" Jeep applications where they do a slip-yoke eliminator (SYE).  Double-cardan unit with a probably generic Spicer 211229X/Neapco N2-83-388X flange and uses Spicer 1310 series u-joints.  The TX10 flange is equivalent to Spicer 2-2-1309.  They're fairly similar, dimensionally, but an adapter is needed.

 

I fired up my CNC router to make a mock-up adapter based on Nissan Nut's version.  He pockets one side to hide the hardware used to attach it to the TX10, and then has threaded holes bolts to attach the Spicer flange to it.

 

 

I eventually realized either it's not a good design, or I still can't understand half the stuff he writes.  Probably both.  There's not really a good way to get a wrench on those bolts.  Use of socket bolts wouldn't be much easier.  (I came up with what I think is a better design, discussed below.)

 

 

As far as clearances go, this should do nicely!  Clearance over my crossmember is perfect.

 

 

 

At full compression, there's "enough" clearance under the sway bar.

 

 

This is what full compression would look like (I didn't have the bump stop pads welded on, but you can see I'm nearly maxed on the coilover), but I will be limiting compression beyond what is shown in this pic, so my max compression will be less than this.

 

 

After confirming the driveshaft fitment and clearance is good, I went back to thinking about the adapter and bastardized my v1 to make it v2:

 

 

 

This actually uses rear wheel studs for the truck and the leftover axle shaft studs from when I did the disc brake swap.  The lengths on these not only end up being perfect, but they're the same size and thread as the OE hardware for both the TX10 flange and the H233B flange, so I've got new OE hardware on order to replace everything (I still need to pull the rear diff to swap gears).  This adapter will be 3/4" thick, with 1/4" pockets for the stud heads.  Master TownDawg will be producing the finished piece from aluminum, since neither of us are convinced redwood is a suitable material.

 

And unrelated to the SAS, I bought new terminals and really like them.  I made something similar using replacement lugs and terminals, but this is way cleaner and better for some of the stuff I need terminals for.

 

 

 

 

Ok, that's it for now.  Getting closer to having it back to being on the ground.

[Slartibartfast]

Sucks about the surprise baptism, but better for it to happen in the shop than on the road!

[hawairish]

18 hours ago, Slartibartfast said:

Sucks about the surprise baptism, but better for it to happen in the shop than on the road!

 

Absolutely!

[fleurys]

beautiful... Love your posts.. keep them coming

 

[hawairish]

Well, this weekend was very productive.  Wasn't able to roll it out, but we're getting close.  Last update I mentioned the axle was being done.  It's officially done and back on the truck.

 

 

 

 

 

 

The bulk of the weekend was getting the axle back under the truck and slowly completing the final assembly.  Right now, everything's torqued down and ready to go.  Axle's centered, thing's aligned as best as I can get them with my eyechrometers.  Got it to the point where the truck is resting on the axle, and tires were slapped on for a while.

 

 

Still needed to tweak the steering stabilizer a bit.  I finished up the mount v3 today and it's finally in a position where I don't think it's going to contact anything. 

 

Also figured I'd work on the center caps while some parts baked (powder coating).

 

 

Limit straps, driveshaft adapter, and custom brake lines delivering tomorrow, among other small goodies.  Been waiting on the brake lines to start the ring and pinion swap in the rear, so hopefully I get started on that mid-week.

[hawairish]

Falling behind on updates again...

 

My guys' trip to Moab has come and gone, but unfortunately the truck was not ready in time for it.  I still made it up there and had a great trip riding shotgun in Towndawg's truck (recently fitted with 4:1 t-case gears and a rear ARB locker...front ARB didn't get installed in time).

 

Long story short, I was able to get the truck out of the garage and around the block a few times, but the steering and alignment didn't feel right, and the gear box started leaking.  I had already rebuilt the power steering lines again (they had sprung a leak a 2nd time) so I have little confidence in their ability at the moment, but they seem to be holding now.  This time around I snugged the fittings up a little less thinking maybe I was over-tightening them and compromising the liner.  But frankly, if they're this sensitive to assembly, I probably don't want them.  For now, they'll do.  Parts are on order to rebuild the gear box, which I probably should have done in the first place.

 

Beyond that, the setup has not been tested at all...but at least it drives now!  Here were the finishing pieces of the build...

 

The driveshaft adapter turned out great:

 

 

 

 

 

 

 

 

 

 

Got the new rear 5.13 (41:8 = 5.125) gears installed.  That took a lot of effort, though.  I've surely mentioned it before, but the H233 used thick rings/spacers/washers of different thicknesses to set pinion height and preload, and practically all of those pieces are either no longer available, or several bucks each (and you don't really know which piece you'd need unless you have the proper setup tools).  It didn't use traditional shims, and even then, there aren't really any good options available due to odd metric sizes.

 

Fortunately, the new pinion gear sat high, so I was able to grind down OE spacer pieces on a flat belt sander.  Unfortunately, it was a lot of trial-and-error to dial in the height (a lot of pressing pieces on and pulling pieces off), and I basically took the pieces down to the minimum factory dimensions to get it as close as I could.  It sucked and took a lot of time, but the pattern is good.

 

 

 

 

I also managed to strip some threads on the bracket that holds the actuator piston for my TJM, so I had to pull that off to weld some nuts on get some threads.

 

I got the switches wired up for the overhead console the other week.  I ran some 8-conductor wiring up the passenger A-pillar and into the engine bay.  Six of the wires are for the overhead panel, and the other 2 I'll wire up for powering a USB port for the dash cam eventually.

 

 

I ended up drawing ACC power, ground, and illumination from the compass module.  Opened it up, soldered on leads, and crimped on terminals and harnesses.  The panel is for a Patrol, and while the color isn't a perfect match for my gray "K" trim, it's close enough for me and I'm super happy to finally put it to use.

 

 

Things are wired up in a way that's consistent with their usage; i.e., you can't engage the front locker unless the rear locker is engaged, and you can't engage the sway bar disconnect or rear locker until the compressor is on.  Remote Air is for the tire inflation setup; it can either hold the air, deflate, or inflate. 

 

 

I was not able to get the compressor, relays, or solenoids wired up until last night, and tonight I needed to sort out some leaks from having to shuffle around my setup.  These are not the finished pics, but close enough for now.

 

 

 

I opted to use some modular solenoids that stack together instead of the ARB style solenoids...that 4-solenoid modular unit costs less than one ARB solenoid, but was a little tough to find.

 

That funky rubber boot thing is an adjustable pressure sensor switch that I was hoping to use for the tire inflation (Remote Air) switch, so that it would stop inflating at a set PSI.  Unfortunately, it's so sensitive that it'll just flutter at the set temperature and cause the compressor to keep cycling.  So, I'll probably just retain it as a safety cut-off.  Also determined tonight that gauge is garbage...it's way off.

 

Lastly, this is how it sat as of yesterday before a powerwash.  I spy something SASsy.

 

[adamzan]

Damn.. looks like it was meant to be that way.

[hawairish]

It's been a minute and I hate to say this project is still not done.

 

I think somewhere since my last post I had another power steering line failure (I've honestly lost count) and then there was a fight were I spent weeks trying to remove the pitman arm off the box, having destroyed a pitman arm puller and time spent waiting for oddball-sized sockets and such, all while just coping with hot weather and declining motivation.  At some point I did eventually get the pitman off using my floor press.  Insane battle...thing wasn't even rusted on or anything, and I tried penetrating oil and heat a few times, too.  Gearbox got rebuilt (hope to never do again), but the repeated steering line failures just shut me down mentally.  ATF is a nasty, nasty fluid and it's frustrating to work around...that @!*% permeates everything, particularly after it's sprayed all over.

 

Oh yeah, I did also install a K&N FIPK kit at some point.  Looks good, no clue if it works because I can't drive the truck or even start it without the power steering system in place.

 

I had a moment earlier this week where out of the 4 vehicles I own, 3 were non-operational, and it kind of pissed me off.  One is the Pathfinder, of course.  The other is my 98 Frontier which has been having an issue of stalling immediately after start-up months that I've not been able to figure why, and it basically can't be driven let alone moved.  Then the battery in my 2020 Telluride crapped out.  Fortunately the battery was under warranty and replaced for free.  In the end, the situation provided some motivation to work on the Nissans this weekend.

 

I've been thinking about the power steering situation in the Pathfinder for weeks now and have been dragging my feet to just call a shop to come out and build some custom lines.  I had ordered some pre-made crimped lines from Summit a few weeks ago but the lengths just weren't going to work (the lengths I needed were right in between sizes of 4" increments, and these sort of lines just aren't flexible enough to account for it).  But tonight I stumbled across a style of fittings that, for whatever reason, never seemed to surface during all my searches in the past.  These seem specifically for high pressure power steering, which pisses me off because I was looking specifically for custom high pressure power steering lines the whole time!  Anyway, found a few manufacturers, went with one that seemed the most reasonable in price (i.e., least expensive), and found an online shop that didn't have tax or shipping.  Suck it, Uncle Sam.  This style of fittings looks far more promising, so hopefully it's exactly what I need.  Stay stay stay away from the crap style I bought previously.

 

I think beyond that, I just need to get new brake lines still.  I bought some nice custom ones months ago, but I apparently did not measure correctly as they are too long to be useful.  More to follow soon, hopefully.

[Slartibartfast]

On 7/28/2025 at 2:30 AM, hawairish said:

ATF is a nasty, nasty fluid and it's frustrating to work around.

 

Hopefully the new fittings do the trick and you can escape it for a while!

 

A friend of mine feels the same way about power steering fluid, after going multiple rounds with a dying hydroboost system in a van. For me, it's brake fluid.

 

Weird issue on the Fronty. Have you confirmed that the computer still has power when you let off the key? Would be a weird way for the switch to fail, but I'm reminded of older points/condenser systems that'll do that if the ballast resistor lets go. Only has spark while cranking.

[hawairish]

30 minutes ago, Slartibartfast said:

Hopefully the new fittings do the trick and you can escape it for a while!

 

Hopefully!  They arrive tomorrow so we'll find out if I have the motivation to dive into it after work.

 

This is the video that convinced me this was the better direction.  The company that posted it does steering stuff for automotive applications, and I've since seen similar kits used for hydro-steer setups.
 

 

36 minutes ago, Slartibartfast said:

A friend of mine feels the same way about power steering fluid, after going multiple rounds with a dying hydroboost system in a van. For me, it's brake fluid.

 

Brake fluid is nasty stuff, too.  I'm certain it's not the case on the WD21, but ATF is used in the transmission, power steering system, and transfer case on the R50, btw.  It's a universal fluid that universally pisses me off.  I can't wait to power wash the crap out of the truck.

 

42 minutes ago, Slartibartfast said:

Weird issue on the Fronty. Have you confirmed that the computer still has power when you let off the key? Would be a weird way for the switch to fail, but I'm reminded of older points/condenser systems that'll do that if the ballast resistor lets go. Only has spark while cranking.

 

I think it's just a combination of crappy fuel pumps and the truck sitting too long.  I've had similar problems over the years, and each time the pump had seized and a new pump fixed it.  I barely drove it from 2017-2024.  I last replaced the pump in April 2024 with a new sender unit so I could address the misreading of my fuel gauge and install a new fuel temp sensor, which had failed and was throwing a code.  Commuted with the truck from April to August, and it ran fine, but it's been sitting since September.

 

The truck will start up instantly, every time.  And always a good start, not just stumbling over.  It just stalls out maybe 5-15 seconds later.  Won't idle or won't rev, for the most part, and has not thrown a code throughout all of it, not even for a misfire.  I've swapped the fuel pressure regulator, fuel filter, and vacuum tubing since they're inexpensive and easier to change out than pulling the bed.  I put a pressure gauge on the line and it was reading 40-45psi prior to starting, but dropped soon after starting.  The fact that it'd always start and run suggested it was at least getting some fuel.  Spark and air were for sure good.  As of the weekend, it was not building pressure...but it was also still able to start every time and run for a couple seconds.  Guessing vapors, but I was kind of surprised.  It never got to the point where it just cranked and didn't start.

 

I had ruled out the fuel pump relay because I can hear it clicking just fine, but I tested it and swapped it anyway.  When the key is turned to ON, the relay engages for a few seconds, the pump primes, and then the relay clicks off.  This time around, I didn't hear the pump whirring, which aligned with the no-pressure reading.

 

Rather than testing the ECU for power after the key is off, I tested the fuel pump relay to see when it was turning on and off.  The pre-starting signals were good.  When the truck is running, the camshaft position sensor that's integrated into the distributor tells the ECU to keep the relay closed.  The ECU controls the relay.  A faulty signal from the CPS will tell the ECU to open the relay, which will cut fuel.  Since the relay remained closed several seconds after the engine had stalled, it means the CPS (and distributor) and ECU are fine.  And apparently, a bad CPS signal won't throw a code according to the FSM.

 

Beyond that, no codes present, a functional relay, and no pressure seem to suggest the pump has seized again.  I have a new one coming, but before pulling the bed, I'm going to see if I can "shock" the pump loose by alternating the polarity on the leads or smacking the tank with a mallet a few times.  Pulling the bed isn't difficult, but still sucks to do.

 

Not sure I ever shared pics or info of my Frontier, but we got it new in 1998 and it's just been passed back and forth between my dad and I since.  In 2021, I swapped in an H233B, WD21 discs, LSD, and 3.9 gears into it.  In 2022, I tore it all down to the body and got it all repainted.  In 2023, I redid the interior carpeting and headliner, including adding insulation/sound barrier stuff, and getting a set of LE wheels repaired and powder coated.  Got it all tinted mid-2024.  On the last day I was going to use the truck for commuting in August (I had just bought a new car and was picking it up a couple days later), some fskchead hit the truck.  The damage was super trivial on the bedside and it's since been repaired, but I've not driven it since.  That accident is still an ongoing @!*%show...last I heard, he was still trying to sue me...yes, after HE hit MY truck.

 

Anyway, here's how it sat when it was still on the road.

 

 

And here's the proof I changed the fuel pump last year, lol.

 

[Slartibartfast]

Yeah, WD21 PS uses ATF too. This made me assume that ATF was good enough to top up the PSF res on my friend's van, which led to one of the more puzzling things I've seen a vehicle do. Over the next couple of hours, it pissed all the ATF I'd added past the pitman shaft seal, while somehow holding onto the old burned GM PSF, or at least enough of it that we didn't lose power steering or brakes. Maybe PSF has slightly larger molecules than ATF. Maybe the fluid was 90% stop leak by that point. Or maybe that van ran on spite more than it ran on gasoline.

 

If the fuel pump is priming enough for that initial startup, that suggests it's not seized. It just can't keep up, which is weird. Weak pump would make sense. I'd be tempted to swap out the rubber lines on the pressure side, in case one is falling apart and blocking itself off somehow. I assume you've thrown a filter at it already.

 

Fronty looks clean! Too bad there's no access hatch for the fuel pump like there is on the WD21/R50.

[hawairish]

33 minutes ago, Slartibartfast said:

If the fuel pump is priming enough for that initial startup, that suggests it's not seized. It just can't keep up, which is weird. Weak pump would make sense. I'd be tempted to swap out the rubber lines on the pressure side, in case one is falling apart and blocking itself off somehow. I assume you've thrown a filter at it already.

 

Yeah, that's the thing.  It was putting enough pressure a few months ago, but as of the other day it's not putting any noticeable pressure.  I also don't hear it whirring when the pump relay clicks, but it was whirring a few weeks ago.

I swapped out some of the hose when I installed the pressure gauge...there's only about 1' of hose that's not been replaced in the last 2 years, but I'm going to try pushing some air back into the tank just for kicks.  New K&N fuel filter went on a few weeks ago.  The air filter is otherwise fine...issue doesn't change when it's removed.  Pulling the vacuum lines off the throttle body and FPR made no difference.  Leaning towards something with the pump.  Haven't ruled out rodents on the tank, lol.

Edited July 30 by hawairish

[Slartibartfast]

Ah, yeah, that sounds like it's good and dead then.

 

Funny you mention rodents. I had a packrat on top of my gas tank the other day. Had this weird noise like fuel was sloshing, when the truck wasn't moving. I'm not sure what the little guy was chewing on or kicking or what, but it led me right to him. Naturally he also crapped all over the intake manifold.

[hawairish]

Ordered new brake lines (again) tonight from HEL Performance.  First ones I got seemed like good quality and price, despite never installing them.  Hopefully this time I ordered the right length...I've found it difficult to simulate the full range of movement these might see that also allows them to move without contacting other things.  The new ones will be about about 26.5", or about 4.5" longer than stock at 22" (from mounting clip to center of banjo).  The Rogue ones I've been using forever are 25", and they're still attached and seem almost right, but I just need a little more slack and movement.  I previously ordered 31.5" ones, which were just comically too long, but seemed like what I needed at the time.  Hopefully I can find another Nissan SAS guy in the FB group that can help me recoup some money.

Speaking of money, tonight's purchase has me over the $5K mark for all parts, tools, and supplies (purchased, sold, returned), and $6K after tax and shipping.  Having a personal machinist in @TowndawgR50 has been a real project saver.  I should be able to recoup another $500-$800 in leftover, unused, or rebuilt parts.  At some point I'll rebuild the R200A with 4.6s and a Lokka and get that out the door.  I have enough parts to rebuild the CVs and steering rack, but not sure how I feel about doing that work.

[hawairish]

New lines (silver fittings) made and installed!

 

 

 

 

PTFE hose vs. rubber.  Same ID, both steel braided, both with fabric cover.  The rubber hose just feels better, and while I still think the PTFE can withstand the working pressure, it was the end fittings that make all the difference.  The new fitting style just feels superior to the PTFE ones.

 

Installation of the new fittings wasn't too bad.  Less prep work required for the hose; it cut easily with a mini-cutoff saw I have.  The only tough thing about the new fittings was preventing the hose from untwisting in the outer nut piece when tightening the main fitting thingy in.  It takes a fair amount of torque to tighten it, and because the hose installs into the outer nut as left-hand threaded, it wants to twist out.  I had to misused some non-marring jaws on my vise to hold the hose stationary.  Maybe I didn't lube it up enough, but eventually got it.  

 

 

 

 

 

Those hoses are rigid enough to stay in position.  Good clearance all around, shouldn't interfere with belts and radiator fan.  I'll find out the hard way if they ever do.

 

K&N installed the other month...mostly straight-forward install.  Heat shield didn't line up the way I expected, so just had to make a new hole.  Also, this gave me a little more room around the fittings coming off the steering gearbox.  There was room with the factory air box after it was shifted over and raised up a little.  Definitely not a requirement for the SAS...but I figured why not.

 

 

After topping off the power steering reservoir and cycling things a few times, I was stoked to see that the hoses had not grenaded!  No leaks, no squeals, no nothing, which is great.

 

Took it for a ride in the neighborhood and around the block a few times.  The first trip was sketchy!  Truck was wandering pretty badly and there was a lot of slop in the steering wheel.  Fixed the slop easily...it was just an adjustment on the steering gearbox that I left loose when I rebuilt the box.  Guess I could've tightened it up before the drive.

 

Fixing the slop fixed the majority of the driving issues.  It was still wandering a little, and steering was a bit tight.  I increased the caster to be more positive, but it did not seem to improve the wandering or self-centering.  Changing the caster means I need to adjust the drag link a little to correct the steering wheel, but I suspect the toe is also off a little, and maybe I'll fix that first to see what changes.

 

There may still be other tweaks I need on the suspension.  Feels a little hard hitting dips, but otherwise the streets feel smooth.

 

Anyway...I was able to put 10 miles on it today, which is pretty huge.  Acceleration feels laggier than I recall, but I'm sure the 114°F temp and 5.12s gears are surely factors.  AC still works well, the ABS tone rings are doing their job, the engine is nice and quiet and maintained temperature (not sure who recalls all the mild-overheating issues I was going through before the SAS started).  I mean, it better maintain temp...I replaced nearly every damn part on the system.

 

For now I just need to sort out the remaining steering/alignment issues, get some miles on it to get the ECU emissions ready, get it tested, and get the tags renewed (I'm just a little late on those).

[hawairish]

Pulled it out to give it a wash today.

 

 

 

 

 

 

 

[tmoore4512]

Been following this for a while, and it looks great!

 

Helluva job dude!

[hawairish]

Took the truck for about a 45-mile drive on Saturday to get it emissions-ready...and it's ready.  The day didn't go as planned in terms of driving it and taking it straight to emissions, and annoyingly, when I got home I saw that there's a pending P0430 code.  I can still get it tested in that state, but I'm screwed if the code becomes "stored".  Fingers crossed I can get it through emissions before it stores.

 

Overall, the truck did well!  Got it up to 75mph without the axle falling off (there's still a vibration from the rear that was there before the SAS).  It still wanted to wander a tiny amount, but manageable.  The toe is dialed in, but the caster may still need some dialing in.  Steering is still a little on the heavy side, even after removing the stabilizer.  I may need to explore options for a smaller pump pulley, perhaps.  Brakes work great.  Acceleration seems to suck, but I feel like I was facing some issues before the swap.  During the project, I had swapped out the radiator...the truck ran nicely right at 185°F the entire trip, no overheating...which was an issue before the project.

 

I tried to find some dirt near the end of my drive, but the little spot in the desert I was planning to check out has since been gated off.  I had to settle for some gravel under an overpass.  Gears, lockers, and sway bar disconnect working just fine.  No real articulation test, and being so close to the road couldn't really kick up any dust.  Once it's through emissions and re-registered, I'll do a shakedown.

 

The only thing that is completely baffling me right now is the speedometer.  It's way off, and in the wrong direction...it reads slower than actual.  I'm expecting it to read about 5% faster than actual, but somehow it's about 8% slower than actual...which makes absolutely no sense.

 

I've confirmed (as I already knew before) that the speedometer gets a voltage signal directly from the ABS control unit based on the wheel sensors.  There is not a mechanical or electrical speedo pinion on my t-case like there was on older/other Nissans with the TX10/A.  There is a VSS turbine sensor on the transmission, but everything in the FSM says the signals come from the ABS system.  My OBDII scanner displays live data and all 4 sensors were reading in unison when expected (the rear tone rings being my control data), but interestingly, there is a VSS data point that also seems to read the same.

 

Notably, the wheel sensor speeds were all about 6% slower than the speedometer, which was about 8% slower than actual as measured with GPS (via my iPhone which is spot on in my other newer vehicles in stock form).  In real numbers, we're talking like 52 mph on the sensors, 55 mph on the speedometer, and 59 mph via GPS.  It makes for a delicate balance when the speed limit is 55, I need to be positively in the 53-60 mph range for several minutes, and not get busted for speeding in a truck with expired tags (though technically, I got a 3-day restricted use permit to do this drive), without pissing off other drivers.

 

But anyway, it just doesn't make sense.  I've crunched the numbers on this multiple times...I have a full blown spreadsheet that handles all my what-ifs and calculations.  My tires are about 13% larger than stock (32.7" vs 29.1") and my gears are 17.4% lower (4.363 vs 5.125)...so I'm expectedly over geared by 4-5%, not under geared by 8%.  The truck seems to behave like it's over geared in terms of acceleration, but I'm trying to figure out why the speedometer is so far off.  Even if I can re-index the needle on the cluster, the input signal is still what's ultimately too low.  There's not really a good way to boost the voltage signal up, but I'm all ears if there's any EEs in the crowd.

[Slartibartfast]

I'd hazard a guess that the vehicle speed data point is the average of the four sensors, so it's feeding the speedo (and likely the engine and transmission computers as well) a single data point instead of four. Wouldn't explain the discrepancy between that data point and the speedo, though. That's bizarre. Maybe it's checking that average wheel speed against how fast it thinks it should be going, given the engine RPM and what gear the trans is in, getting confused because the ratios aren't what it expects, and attempting some kind of correction?

 

I've heard of speedo calibration boxes that apply a conversion factor to the speed sensor signal. Seems like it should work, provided the speedo's getting a pulse signal, not reading the data point via canbus or something.

 

Good luck with the inspection! Sucks the cat is still giving you issues, but at least the cooling system is finally working right.

[hawairish]

It's as good a guess as any, so I'll take it.

 

I think it's an average, too.  I don't think my scanner has very granular data units, and I suspect it's programmed to do its own conversion of voltage to speed based on "Nissan" vehicles that's slightly different from the speedometer.  It's reasonably close, but I trust the speedometer more than the scanner.  It's just useful to confirm that the wheel sensors are functioning.

 

The FSM shows no other data inputs to the ABS system beyond the wheel sensors and the G-sensor, unless I had the all-mode setup or VDC.  VDC-equipped trucks do use CANbus.  But otherwise seems very clear cut in descriptions, diagrams, and schematics.  Single wire feed from the ABS unit to the gauge cluster.

 

A speedo calibration box is basically what I need to find and just put it on that wire.  But still, the total offset I'm seeing just doesn't make sense.

[hawairish]

Alright, got it through emissions and re-registered!  Only 8 months late...

 

Last night I installed a non-fouler on the downstream driver's O2 sensor and it seemed to do the trick.  Not only did the P0430 not move to stored to screw up my day, but it's also no longer in pending.

 

Steering was a little more squirrelly today.  I need to get to the bottom of that.  But otherwise, the truck is operational.  Hoping to do a shakedown run soon.

Edited August 20 by hawairish

[system_f]

It's been a minute, and I haven't been up to date on where your R50 was before the SAS.  So anything done that isn’t pictured I am not aware of and it may make the comments seem redundant.  I have a couple of questions and some comments.

1. Rear vibration you are experiencing.  Did you do a hack and tap slip yoke on your rear driveshaft?  That was the only way I could get rid of the rear vibration when I was 6" ++ lift.  

2. Steering: Toe and Camber, you'll find the right settings.

I have two questions for you.  These aren’t criticisms, I’m in no place to criticize this kind of work, but I am curious about your thought process?

1.    What about side-to-side bracing, under the radiator support?  Something to replace what the subframe did.  This may be completely unnecessary, but what are your thoughts?
2.    Strut tower bracing.  Do you think the strut towers are strong enough?  I know they were designed to handle the vehicle load, again, your thoughts.