SkiMachine

Uhhh, Tapatalk kept telling me this post was not submitted since I was posting too fast (even though I had not posted anything recently). Apparently this was not the case. Can a mod please delete all the other threads and merge any replies in those threads into this one? Thanks.

Here's the PO's solution to a broken exhaust stud on the passenger side: Stove bolts are high-strength rated, right? [emoji6] I saw this when I purchased the truck but at the time everything else looked good. In hindsight this should have been a monumental red flag and I have paid the price dearly since. At the time I thought it would be a straight forward drill out and replacement with the correct stud, until I saw this: Not on centre at all. And it appears that he was drilling even further away from centre (and into the head) the further in he went: . (this is a new, straight stove bolt) Good thing he only drilled about half the length of the original threads. So basically it looks like the existing threads are probably done for, which will mean there is no backing this stud out. I'm assuming I can drill out an extra size up to get a heli-coil in without hitting a water jacket, but what I'm struggling with is how to get back on centre to do so? Any ideas?

The best way to replace one of these transmissions is to pay somebody else! I'm about half-way through re-installing mine and will never do so again. I'd rather ride a bicycle 30 km to work in a -20C hail storm. Naked.

Dead upon purchase? Who knows what really happened to it then, unless the PO is family or something. Time to go down the checklists in the FSM. As others have said, a line pressure check would be a good place to start. The magnet in the pan is another good indicator of what really happened since it is unlikely the PO pulled the pan if trying a fluid change quick-fix. Once the pan is off the solenoids and VB are right there if the evidence suggests they're the culprits.

How long has it been in there and what does the fluid look like? The stock cooler obviously competes with engine heat anyways, and that new one is a good size. Good call on getting max airflow from the fan.

+1 on the above. Unless you know and trust the PO really well assume nothing has ever been changed, and/or the wrong stuff was put in if it was. To the OP's problem - If the AT light is blinking at startup, then you have a TCU code and should check it. It might provide some insight.

.... or it could be you are down an injector, as you've said in the other thread..

The timing marks are probably telling you the truth from the sounds of things. I'd verify your overall valve timing right away since that is what this is starting to sound like. I had an issue last year with very similar symptoms. In particular no power at all at sub 1k RPM - it got to the point I could not even get the truck moving from a stop if it was facing uphill. The upper TB cover can be removed fairly easily, from there you can verify your cams are at TDC using the marks on them/TB cover rear plate and the crank pully - or a drinking straw stuck into cyl #1. You can also inspect the belt its self for signs of missing teeth and wear. Also, the middle of the timing marks is probably where you want to be - the first (left) most is TDC, with the middle being 15 deg before TDC. If you are to the left of the first mark, then you are after TDC which would be why you have no power at low RPM. It makes sense once one realizes the ECU advances timing as the engine speeds up - the spark starts to occur closer to TDC if your timing is otherwise retarded. ATDC ignition will often lead to backfire, and knock. Any of that going on?

The brass debris is telling - The reverse clutch drum bushing that mates up with the pump stator is a brass (friction side) / steal combo. This bushing is indeed known to fail - it is what happened to my transmission, and almost happened to the used reverse drum I bought to replace it. Someone else posted on here last year detailing the same issue with their tranny as well. Once this bushing wears to its steal backing it's all over. The wear becomes exponential at that point, with shards of steel breaking off and traveling through the transmission, in turn doing more damage. The mating surface of the stator and reverse drum took quite the beating in my case, but then I drove it for months after reverse failed The excess play will also lead to the stator to drum reverse circuit seals failing - usually quite suddenly hence all of the no warning loss of reverse cases one reads about. A chunk of one seal was missing in my case. All of the other bushings are aluminum and seem to hold up much better - I have no idea why Nissan made just one out of brass/steel but it is a weak link for sure.

By chance did the ECM or its connectors get wet? It is under the front passenger seat thus is vulnerable to being flooded out. Like dropping a cellphone in the water, it could work ok during/immediately after but then start failing a few weeks later as the corrosion (both connectors and PCB) sets in. Just a guess though.

Yeah that seems to be the consensus. If my rebuild doesn't work out then an Xterra tranny will be my next move. Good on ya for finding a good unit. In case you've missed the other threads on the subject, don't use the stock cooler and flush those cooler lines.

First mistake: Don't "expect" any problems - that's negative thinking! You are driving a WD21 Pathfinder, it is basically a tank without tracks. It is made for this type of duty, in fact, I would be more concerned for your pathy's well-being if you had only driven on dry pavement all weekend. More specifically, I would feel sorry for it. If it did not die at the time (water ingestion), then a check of your fluids (in particular the diffs as mentioned above, plus tranny and T-case) for water ingress is all you need to do. Google will be your friend for how to perform these checks. If you do find water, it is time to replace seals since this shouldn't happen. Stock electrical connectors (stock connectors have rubber seals in them, and are mostly placed up high), so likely no problems there. It probably wouldn't hurt to get underneath and pump grease into every grease lug you can find in case anything got washed out. But I think you have nothing to worry about.

That's a good deal considering the effort involved in pulling these beasts. I spent a bit of time trying to find a doner tranny here to no success thus I'm rebuilding mine (after shelving the project over the winter). FWIW, in my case reverse failing was due to hard parts damage leading to a compelete reverse drum to stator seal failure, not a stuck valve. Though reverse simply went and never came back on my transmission. If the problem is intermittant it could indeed be a stuck valve. I mention this since the VB can apparently be worked on on-vehicle which saves a ton of missery (pulling the whole tranny is pure hell). See my thread here for a bit more detail re the potential hard parts failure. If the tranny does need to be pulled, then the Xterra HD option is the way to go. I'd take a real good look at the magnet, fluid color, millage, etc on the donor tranny before lifting it into the truck though. If anything seems off, find another or have it rebuilt. This is not something you want to have to lift in/out twice.

Hi. Does anyone know of anywhere else I can buy authentic Nissan parts? Nissanpartszone.com looked promising, but they apparently have some bugs with their address verification system thus I can't order from them. Can't say I appreciated the complete waste of time, but that's life. I'm getting back to my transmission rebuild and need a couple valve springs, and a new pump cover. Not exactly stuff I can pick up from the local NAPA. The "local" dealer is 2 hours away, and expensive.. Thanks.

Also - the band is only applied in 2nd and 4th.

Which gear is it slipping in? The band adjustment is an allen key screw with a lock nut. I'm pretty sure it is located on the driver's side, facing up, not too far behind where the bell housing meets the transmission. I'm not sure what access will be like with the tranny on the truck - but assume it will be bad. Look at the FSM in the rebuild section - I think in the part that details the re-installation of the reverse drum assembly. FWIW, I think you're running the risk of having the band wear down to metal-on-metal at which point you'll be replacing hard parts.

Documenting it is kinda the goal. It's surprising how little info there is out there on this subject, despite a loss of reverse being the typical failure mode for these transmissions. Here are some somewhat better photos, with annotations: Front Drum: Front stator (on oil pump): Both of the above as they would sit together in the tranny, for clarity: Stator/Drum bushing. The diagonal grooves should spread oil evenly across the surface. The new one has grooves facing the same direction, where the old one had opposing groves pushing in opposing directions, I'm not sure if the change is intentional. The stator has lube circuit ports that inject oil "under" this bushing (into the diagonal grooves) to keep wear to a minimum. The inside of the bushing (and only this bushing) is copper or brass. Any loss of lubrication due to plugged fliters, bad seals, cooked/old oil, or abrasive material in the oil, etc would be disastorous for this bushing given the softer metal on the wear surface. If you take a good look at edge of the worn bushing, you'll see a shard of metal coming off of it (top of photo)... not good at all. Difference in thickness was about 0.25mm, or .5mm inner diameter. I'm pretty sure the stator has worn down by a mm or so diameter as well which adds up to quite a bit of play.

Yeah if I get this thing back up and running a inline filter will be installed for sure. I already have a Hayden cooler ready to go on the truck. The stock rad cooler was still in use, and judging by its condition, pre-dates the previous rebuild. It's unfortunate that someone went to all that work/expense for a rebuild and didn't pay attention to that detail. I think I can get this back on the road if I replace the reverse drum and the oil pump, along with that drum's bushing, which came in the bushings kit from Rock Auto. Everything else seems fine, except some bearings. Speaking of the rear drum's bushing - metal shards were apparently being gouged off of it. This seems to be a common cause of this common issue, judging by the description in this post here (off-site), and the photo of the reverse clutch in this post

It looks like that magnet really was the black flower of transmission death. Something clearly did some bouncing around in this tranny, and it did some damage. Ultimately what ever it was tore a chunk of the first of two reverse clutch sealing rings out of its grove on the oil pump cover's snout: Looks like a part of the missing piece got wedged up on the other side: Note that's not debris on the edges of the seal seats - they're ground up and jagged. Thus the oil pump cover is a lost cause. Coupled with the suspect clutch pack and I'd say this transmission is toast. Any thoughts? FWIW, the friction plates in both the reverse clutch and high clutch are in like new condition - they measure in at standard, nowhere near the wear limits. It had to have been rebuilt not too long before I bought the truck.

That fluid is basically black without a light right on it. When it's shallow it still looks red-ish, maybe. So far the only thing I've seen that is suspect (other than the fluid and that magnet) is the edge of the front low/reverse clutch housing where it mates up with the rear housing of the same clutch pack. It's rough and appears to have impacted with something. Some of the needle bearings are also not as smooth running as they should be, but that's most certainly more symptom than cause. The reason for all of this is that reverse stopped working suddenly. The warning sign that something was amis was that the transmission would randomly decide it didn't want to shift into second anymore - after reversing. This problem occurred very occasionally, and wasn't reproducible which didn't help my troubleshooting attempts. Then suddenly, blamo, no reverse at all.. The history behind this is in this thread: http://www.nissanpathfinders.net/forum/index.php?/topic/null-VG30-Timing-/-No-Power-Issue In other words, I'm one of those "I drove it for six months without reverse" types. Though the metal dust on the magnet suggests I should not have. There is currently about 220,000km on the clock for the truck, not sure about the tranny. There is clear evidence this beast has been off the truck before. Newer, non-stock (non removable) zip-ties on wiring that needs to be removed to get the tranny out, a missing (if the FSM is accurate) oil tube clip on the valve body. Plus the loose crankshaft pulley bolt - which could have easily been loosened while someone was tightening torque convertor bolts on to the drive plate.

See the attached image. It's from my 94's RE1R01A. That it so clearly demonstrates the magnetic fields is really cool. The black stuff looks like metal shards, end-to-end radiating outward like hoar frost. I'm not sure what the grey stuff is - it has the consistency of sludge/jelly. I'm also not sure what this means for my goal of rebuilding this thing. Tearing it down now, so we'll see... Debris in filter... This is not rum, though i could use a drink right about now...

Does your scan tool allow you to view TCU output in real time? If so you could watch for the A and B solenoids to be commanded off while you have someone drive for you - If that occurs and it still does not shift to 3rd, then your problem is definitively mechanical in nature. The solenoids could be sticking, or clogged. The black fluid would not have done them - or anything else - any good unfortunately.

Just to clarify - The issues started after the transmission flush, or was that an attempt at fixing the problem? What was the fluid quality like pre-flush? Have you gone through the whole list of diagnostic tests in the FSM for that year? From that FSM: For the D1 to D2 shift timing issue: 1. Throttle position sensor (Adjustment) 2. Vehicle speed sensor·A/T (Revolution sensor) and vehicle speed sensor·MTR 3. Shift solenoid valve A 4. Shift solenoid valve B All technically on-vehicle serviceable, if you have a warm garage to work in. Oddly enough, item #2 apparently will not trigger a ODBII code and needs to be sauced out with the O/D blinking light test. For the no D2 to D3 shift issue: 1. Park/neutral position (PNP) switch adjustment 2. Manual control linkage adjustment 3. Shift solenoid valve B 4. Control valve assembly 5. Vehicle speed sensor·A/T and vehicle speed sensor·MTR 6. High clutch 7. Brake band 6 and 7 would mean it's rebuild/replacement time and would likely be accompanied by slippage I'd imagine. I'd obviously focus on the two common items, the speed sensors and shift solenoid B first. That said, IIRC 3rd occurs when both solenoids are off, which is why limp mode uses 3rd - unless something has changed from my 94'. The PNP switch and manual linkage are also worth checking. The first can cause the TCU to not even try to shift into 3rd, the later may prevent the valve body from doing so.

The coolant connector/sensor is probably a red herring. It's a symptom of the problem, but not likely the problem. That you can plug it back in after the truck has been running makes sense given the coolant temp will rise very quickly once started. I also doubt the knock sensor would be causing problems at idle. My understanding of the KS code is that it's triggered once the ECM decides the readings are "unreliable", i.e. open or short circuited. Be sure to check the fuel pressure. At idle it should be at 34psi, and at WOT it should be at 42psi. The insidious thing about the fuel pressure regulator is that it's at rest (engine off) target is 42psi. This is because it takes engine vacuum to pull it's diaphragm down to the 34psi target, and is also why it goes to 34psi at WOT (no throttle restriction = little vacuum). It is quite possible - likely even - that the fuel pressure reg got "stuck" at 42psi when the truck was sitting for so long. A vacuum leak would have the same results. Higher than expected fuel pressure would of course mean more fuel into the engine. It'd also completely blow out any emissions tests. edit: The knock sensor is a common problem with our trucks - and an absolute nightmare to replace. edit 2: My pathy had some serious engine issues last spring. I spent a TON of time tracking down various EC sensors/actuators that I thought might be the problem, the whole while ignoring the basics - which is why I think your coolant sensor is a red herring. At the end of the day it was basic valve timing due to a loose crankshaft bolt and a almost completely destroyed index key on the timing gear. I was probably within a week of it completely freewheeling and destroying the engine by the time I figured it out.

Take a look at page EC-23 (1994, 93 may be different) in the FSM - to summarize it states the ECM will assume the coolant temp is 20C at start-up if you disconnect the sensor. The ECM aims for a richer fuel mixture the colder the engine is. Thus if the coolant temperature is less than 20C (which I'm sure it is right now, even in Langley) when you are trying to crank it then the ECM will aim for a richer fuel mixture than it would with an assumed (ECT sensor disconnected) temperature of 20C. In other words, when you disconnect the coolant temp sensor the ECM is aiming for a slightly leaner mixture. This matches up with your description of it running really rich. With outside temps lower than 20C, the fuel mixture might be too rich to ignite. At the assumed 20C, it may very well be just lean enough. There are a bunch of possible causes. The FSM's diagnostic procedures include fuel pressure and injector tests pretty high up on the checklist. Both of those items could easily cause a run-rich situation. Keep in mind gasoline goes bad after a while, and moving the truck breifly last weekend may have been just enough to stir sediment up. It could also be timing, or the MAF, amoungst a few other things. All that said, have you taken the time to check the basics? With a truck that's been sitting for a while I would check/replace fuel/air filters, and make sure squirrels aren't nesting in the intake to start with. I'd then check for ECM codes, fuel pressure, test the EGR valve (should be closed at start/warm-up), test the PCVs, and the plugs/wires/coil for good spark.