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Some Quick Help Needed


drewp29
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Ahoy Hoy everyone!

 

So my 2002 Pathy has been pretty reliable, and recently rolled over to the 210,000 mile mark. The only real issue with the engine has been the oil consumption, but I can deal with that, it takes about 1-1.5 quarts per month. However, I noticed last week that the rattle that usually becomes louder when I need to add some oil was getting quite annoyingly loud. I checked the oil and added about a half quart to bring it up to the middle of the hatch marks, and the noise persisted.

 

Yesterday it was freakin loud. So I thought I'd try doing a quick oil change to see if i could quiet it. No bueno. So I did some research and determined it was either the timing chain or rod knock. Took it to a shop this morning and they diagnosed it as the timing chain. Since the cost to replace the chains etc. was quite ridiculous, I started looking into doing an engine/transmission swap with a lower mileage motorset. The labor cost for the swap is only 4 more hours so quite worth it if I can find a good lower mileage engine and tranny.

 

My Pathy is a Manual Tranny 4x4, so I looked for engine transmission combos, but none were to be had. I found a decently low mileage transmission for a good price, and it comes with the transfer case, so should just be a bolt on affair. I had been planning on replacing the clutch anyway, so no big deal if buying motor and transmission separately does not include one.

 

Then I found a gold mine, an engine with 34,000 miles, practically brand new. HOWEVER, it is from an automatic. So my question is:

 

I know the intake plenum on the autos has the power valve crap, but, I have a perfectly good intake plenum on my current engine. Can I swap the intake plenums and use the auto motor as is?

 

I have read through all the threads on motor swaps, and it seems like this is the case, but no one actually confirms that the only real difference in the auto vs manual motors is the intake plenum.

 

Whaddya think?

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There is much more to the transmission than the intake. There are two harnesses that go to the transmission from the chassis. Change your engine but keep your trans, my opinion.

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I get what you are saying, but I think you misunderstood me. Probably because I made it confusing, lol.

 

I am buying a used lower mileage manual tranny (I currently have a manual Pathy, but high mileage and needs a timing chain job $$$). The engine I was looking at is from an automatic. It does not come with a transmission. So I'll need to purchase a clutch and flywheel, which I was planning on replacing anyway since the motor will be out of the vehicle. The question relates to the use of the motor (just the motor) from the automatic Pathfinder.

 

Can I replace the auto motor intake plenum with the one I have currently on my manual motor, and be done with it? Or are there other things that need to be addressed?

 

 

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Can I replace the auto motor intake plenum with the one I have currently on my manual motor, and be done with it? Or are there other things that need to be addressed?

 

Yes. The upper manifold is the same; the lower manifold is AT/MT specific. The blocks are the same, so I can't think of anything else that would be of concern.

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Excellent! Thank you! The 34k mile one is a diamond in the rough I think. Honestly had it been my vehicle I would have fixed the front quarter panel, bumper, and head light assembly and told the insurance to not bother. I mean, 34,000 miles!

 

Most of the threads I read were more about swapping a manual into an auto chassis, so the waters were muddy as to whether there were any other differences with accessories and such.

 

I guess there is one more small question. The engine is from a 2003 and mine is a 2002. The description says it fits 03-04, but I am fairly certain there is no difference between the 01-04 VQ35DE engines, so it should be fine right?

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Oh, and I'm gonna have some things to show off soon. I installed a head unit and speakers, and the tweeters would not fit in the A-pillars with the covers on, so I am going to 3D print housings for the tweeters to cover up the opening on the pillar and point the tweeters towards the front seats. Should be pretty sweet!

 

And anyone who wants the 3D model may have it. It'll be a month or so, but I'll share it willingly!

Edited by drewp29
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01-02 VQ's have a cable driven throttle, whereas 03-04 are drive-by-wire (electric). If your swap from the lower intake up (lower, plenum and throttle body), you should be good to go. I'm not a certified expert, but as far as I'm aware, there aren't any other differences.

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Nice, so just make sure the current throttle body is used. Good to know the difference, having not seen or worked on an 03-04 I didn't realize this difference. Thank you so much!

 

If anyone else believes there is a difference other than Lower Intake Plenum, and Throttle Body, feel free to chime in! I'm by no means an expert either. I know my truck pretty well, but there is definitely knowledge to still be gained.

 

Looking to do a small, maybe 3" subframe drop in the near future as well. The AC lift has sagged a bit and it doesn't look as tough as it did a few years ago.

Edited by drewp29
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01-02 VQ's have a cable driven throttle, whereas 03-04 are drive-by-wire (electric). If your swap from the lower intake up (lower, plenum and throttle body), you should be good to go. I'm not a certified expert, but as far as I'm aware, there aren't any other differences.

 

This is correct. The cruise control unit is also cable driven, but I think the brackets and cable guides are shared with the cable for the TB. Either way, those brackets should already be on the 03 engine (they are on my 04).

 

And definitely, not having a motor in the way would lighten things up and give super easy access to the motor mounts if installing an SFD.

Edited by hawairish
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If you're serious about doing a SFD, it would probably be a million times easier without the engine in way. Just a thought.

 

I thought this same exact thing last night when I wrote that... hmmm...

 

 

Hawairish - you wouldn't happen to have a drawing of the strut top pieces for your 3" SFD would you? I can get the rectangular tubing easily enough for the subframe blocks, but the angles on the strut top assemblies would be nice to have. I know the originals are in a thread from somewhere long ago, but digging them up is always a bit of a chore.

 

:-)

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My strut spacers are just two stacked 1.5" spacers, no angles involved. I've got a single set of camber bolts to align it.

 

Ah, I understand. So you have stock coil height right? When I installed the AC springs and 1" spacer in the front, I slotted the top hole on the struts, and used camber bolts, and I was pretty much maxed out on everything in order to bring the alignment to about -0.3 degrees. I think with the sag I'm probably right around -0.5deg as my tire wear is still even and the tires are pretty much square to the ground, so it can't be much more than that.

 

I joined the R50 Facebook page, and downloaded the SFD Word document, which has enough info in it that I may look at building some strut mounts. I have access to a CNC plasma table at work, so cutting the flanges is no big deal. I may be able to convince our shop supervisor to cut some pipe for me as well, so all it would take is welding them up. 3 1/2" sch. 40 ought to work nicely.

 

Decisions decisions. I may not be able to take care of these things before I would like to have the Pathy back on the road. My parent's are letting me borrow one of their extra vehicles for the time being, but I'd like to give it back to them as soon as possible. Oh well, if it doesn't happen now, I have a few jacks and an engine hoist in my garage, so doing it later may not be as easy but it is doable.

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I've got OME MD springs up front right now. It's time to overhaul my suspension, so I will be switching to OME HDs, among several other modifications front and rear.

 

Having the engine in isn't terrible, though. I've run a few SFD sizes on my truck and installed on another. Nothing complicated, just time consuming. I'd say get it back on the road first. With a looming engine swap, that's already plenty of work to handle in one shot.

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I'd say get it back on the road first. With a looming engine swap, that's already plenty of work to handle in one shot.

 

I'm leaning heavily towards this. I think if I am going to go SFD I'll likely want to use 3x2x1/4 tubing and do a a custom strut tower mount for 3 inches. That way I can eliminate the 1" spacer and get an extra 2" of lift while returning the CV angles 1" back towards stock angle. For the rear, and I know it is not ideal, but I found some spring perches for 2 inches of lift, so now I need to figure out if I will need to replace the rear Bilsteins with a longer length model.

 

Oh, and it sucks, but the guy with the 34k mile engine apparently sold it last week but never removed the ad, so there's that. I have an inquiry out to a salvage yard that has one with around 80k to see if they'll do a combo for me with the engine, transmission, and transfer case. I've got my fingers crossed.

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Sorry to hear about you missing that 34K engine. I'm going through something similar myself thanks to NIssan and it's loose Power Valve Screws. See my postings on http://www.nissanpathfinders.net/forum/topic/43931-vq35de-engine-differences/?p=796139

 

Your story has me nervous, I had figured that after so many miles if the screws were going to come out, they would have already done it. I guess not, and now I'll have to do this job this summer now too.

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Your story has me nervous, I had figured that after so many miles if the screws were going to come out, they would have already done it. I guess not, and now I'll have to do this job this summer now too.

 

Honestly, I would do it now. I am sure my truck has swallowed 4 of those screws in the past without incident and it's only this last one that caused some damage. But it only take one. I can't help but think that if I had caught it before I might not have had this problem at all. (admittedly I would have been freaking out about where those others screw were but I might have been able to limit it 2-3 hours work and minimal cost to simply fix the power valve screws & just keep on driving it. My truck has lived a fairly easy life and it's seen Mobile 1 througout it's whole life. I have every reason to believe that internally it was "younger" than it should have been and would have lasted me 200K without problem. All of this has made me sick! It's such a waste of money, time, anxiety, etc. not too mention an engine that was otherwise in excellent shape.

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not sure if anyone else said this or not, but usually the flex plate and flywheel on the back of the motor are different. also the plate that separates the motor from the tranny may be different as well. so transfer what u need off of your old motor over to the new one. have a good one and good luck

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Originally my plan had been to buy whatever motor had the lowest miles, '02-'04 motors only. I apparently lucked out in that I ordered the engine, tranny, and transfer case from the same vehicle, a 2002 4x4 5spd out of NY with verified 80,911 miles. The VIN for the donor and my VIN both check out as 2002 SE model 5spd chassis with effectively the same exact options. So I should be good to go on a straight up swap.

 

The funny thing is, I did quite a bit of searching for differences between '02, '03, and '04 VQ35de Pathfinder motors, and did not really produce anything of substance. I am usually quite good at keyword searches and revealing information that is buried deep in past forum posts. Better than most people I know anyway. That's why I created this thread. I normally do a lot of research before asking questions in order to keep redundant posts to a minimum.

 

The Engine and Trans/TC are shipping on separate pallets, so since they are already split I figured I might as well have my mechanic change out the rear main seal since it really should not add much to the swap price.

 

I purchased a Fel-Pro rear main seal and upper oil pan gaskets: Fel-Pro BS40631 (RMS), and Fel-Pro OS30696 (UOPG) - You need the upper oil pan gasket.

 

I also purchased the lower oil pan gasket: Fel-Pro OS30777

 

I am also going to have them change out the transmission and transfer case oil, so I purchased 8 quarts of Red Line MT-90, 5.39 quarts for the transmission, and 2.32 quarts for the transfer case.

 

I have a Detroit Axle rebuilt steering rack with Moog tie rod ends I am going to have them install as well. I had planned on doing it one of these weekends, but had not gotten around to it yet.

 

Once I have it back in my possession, I have some refresher things I had planned as well. Since I am apparently going to be keeping it for awhile, might as well get those done soon.

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If I had the time I definitely have the mechanical skills to get these back to solid condition, provided the ring lands haven't scarred the cylinder walls beyond repair. It did have quite a bit of blow-by, exacerbated I believe by the need for a new PCV valve, though that's just an educated guess. It would go through about 1.5 quarts a month. It also most likely either needs the rear seal/upper oil pan gaskets done or the o-rings on the oil cooler since for about 2 months now I have had about a quarter sized drop of oil on the garage floor after driving it. I was under it a few weeks ago and determined that it was one of the two based on where the oil on the bottom was localized. I have a new PCV valve, which I am going to have installed on the new engine as a stop-gap measure. With the engine out of the vehicle, it should be really easy to change as well. Since it is my DD, the requirement for removing the intake plenum to get to the PCV valve is what ultimately kept it from happening quickly. That and about a dozen other projects going on at any given time.

 

I do however, already have one engine about halfway torn down for a refresher. Not a total rebuild (at least until I get the head off and inspect the condition of things), but I don't really have any more room in the garage, lol. That's the RB25det NEO for the Zenki. And I definitely do NOT need another project, lmao.

 

I'm sure you have the necessary skills to bring these back to life as well...

 

 

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