Jump to content

Transmission Tear Out Lessons Learned and Questions/Advice


Recommended Posts

@adamzan I guess I did it the easy way and pulled the front axle and everything else associated to it in order to pull off the oil pan and the rear main...

 

Couldn't find a torque spec for the flywheel bolts, so I torqued those to 70#. Clutch is in. Just waiting on a couple of fasteners to show up and I'll put it all back together..

 

Can't find anything on the transfer case, so I'll do some exploratory surgery on it in order to put a new seal in it... It's broke already, can't hurt it anymore... That's the mantra, right? 

 

After taking a closer look at it, the seal on the transfer case has to be put in from the back side of the cover, so it HAS to be split in order to replace it. Hopefully it's easy... and doesn't take any special tools or parts that I don't have or can't get....

Link to comment
Share on other sites

'95 manual says 72-80 lb/f for the flywheel bolts. For some reason it's in the "cylinder block" section. EM-36.

 

Good luck with the case! Hopefully no surprises inside.

  • Like 1
Link to comment
Share on other sites

@Slartibartfast So you're saying I got it pretty close then!!

 

Downloaded the FSM for the transfer case. It looks like the only way to pull/replace that front seal is to take it COMPLETELY Apart. Not quite what I wanted to do... 

Link to comment
Share on other sites

22 hours ago, gamellott said:

@Slartibartfast So you're saying I got it pretty close then!!

 

Downloaded the FSM for the transfer case. It looks like the only way to pull/replace that front seal is to take it COMPLETELY Apart. Not quite what I wanted to do... 

That seems insane.

  • Like 1
Link to comment
Share on other sites

Posted (edited)

@adamzan Agreed. The seal does not come out of the front. There is a slight ridge in the oil cup that prevents it from coming out the front.... In addition to the oil cup that completely prevents it from clearing the mainshaft (Only on a MT. AT doesn't have the oil cup based on what I have seen and read). The cover that it goes into, has 2 bolts at the top that fasten from the other side.

 

I'll get back to this if I experience anything different... it looks somewhat challenging, but it also seems fairly basic. You just have to take things apart in a certain sequence... but it's pretty much completely disassembled in order to get to it. I thought I replaced this in my 95, and I know I didn't have to split the case.... Maybe my memory is faulty... I don't remember that cup being in front of the seal at all... And it was a MT as well... Maybe someone put the wrong transfer case on it... It was a 4 cylinder D21, so not entirely the same... maybe that was the difference... I don't know...

 

I guess... since everything is 30+ years old and I'm going to be taking it COMPLETELY apart, I might as well replace the front driveshaft seal and the gear selector seal... Off to find out where I can get those... 

Edited by gamellott
More Content
Link to comment
Share on other sites

Seals are a standard sizing usually so even if the auto parts store can't get them if you can read the numbers off of them, a bearing specialty shop should be able to find something.

  • Like 1
Link to comment
Share on other sites

Posted (edited)

I reached a stopping point today so I thought I would put it down while it's fresh in my head.

 

For the gear driven speedometer models, remove the speedo gear first. If you don't, you'll probably break the plastic oil cover and gutter. I didn't make the name of it... it is what it is. 

 

When disassembling the rear end of the case, contrary to the manual, do not remove the front driveshaft output nut or adapter until you're ready to replace the seal. The procedure has you remove that first and, in my case, the front bearing came out of the housing vice the rear which misaligned everything when pulling it apart and the chain would not let me pull it apart. If you leave that part on the front of the housing, it will keep the bearing and sprocket on the front housing, allowing for a much easier removal.

 

Now that the extension housing off, the procedure mentions pulling everything off of the tailshaft. Do NOT do any of that. I spent a lot of time trying to pull that apart and it didn't need to come off.

 

Pull the snap ring off of the shift fork that is accessible. That's for the 4WD.

 

Remove the oil cover and gutter. It's plastic, so use care when pulling. I imagine that's probably unobtanium.

 

There are 6 Torx head bolts holding the mainshaft to the housing. Do not remove those.

 

Split the mid section from the front section. This is where parts fell out. Intact. One was a shim that goes on the bearing of the countershaft that resides in the mid section, and there were the 2 pieces of the mainshaft pocket bearing that resides in the input shaft.

 

I removed the 4WD fork rod and 4Low fork by popping them out from the external actuator. There is a ball bearing backed with a spring, held externally with a 19MM plug. I don't know when you should pull those, but when I pulled them, the ball bearings fell into the housing and were easily retrieved with a magnet.

 

From there, you can access the top 2 bolts of the front cover, unobstructed.

 

Putting it back together, I placed the pocket bearing into the space where it goes and used grease to hold the shim in place on the mid section. That's it!! it's basically lining everything back up and doing the same thing in reverse.

 

Since the front driveshaft rear bearing is stuck in the extension housing, I'm going to have to borrow a slide hammer to pull it out and will continue to try to put it back together tomorrow. I'll be ordering a new front driveshaft seal, so, yet another thing I'll be waiting for until it's done. At least, I can start working on getting it back in the Pathfinder and put that in later.

 

All in all, about 5 hours to work on, and if I knew about the things I didn't need to do, or sequence of events, it could have been much less.

 

Hope everyone has a fantastic weekend!! 

Edited by gamellott
Clarification
  • Like 1
Link to comment
Share on other sites

  • 2 weeks later...

The Weekend update:

 

Got the transmission, and rear drive shaft installed. Quite a bit of struggling in order to get the transmission to go in the last 1/2". I don't know what the hang up was, it simply wouldn't go in, then I wiggled my nose just right and clunk.... it went the rest of the way in. I'm hoping nothing was damaged in the process.

 

Still waiting on a couple of things before I can button it all up. While the front end is torn apart, I'm replacing the strut rod and sway bar bushings. I also picked up some Ridge Line manual locking hubs... so far, I'm not greatly impressed, considering they are one of the most expensive ones out there for these. I thought I had picked up a manual set that fit, but the splines don't match up... Back to the Salvage Yard to find a suitable donor?? Or... there are some super cheap OE imitations out there on Amazonia. Maybe I'll look into those.... 

 

Biggest things remaining are the front axle, exhaust and all of the removable crossmembers. Then I have the interior to put back together...

 

With any luck, I'm past all of the cuts I have been getting from sharply machined metal... Most of the reason why I'm not doing it today. Gotta let my palms heal from cuts...

Link to comment
Share on other sites

Maybe you got the early 27 spline hubs? The hubs and CVs switched to 28 spline between '89 and '90. Don't think I've ever seen a Ridge Line hub.

 

Hopefully that's the last speed bump to it going back together!

  • Like 1
Link to comment
Share on other sites

5 hours ago, Slartibartfast said:

Maybe you got the early 27 spline hubs? The hubs and CVs switched to 28 spline between '89 and '90. Don't think I've ever seen a Ridge Line hub.

 

Hopefully that's the last speed bump to it going back together!

The hubs I got from the Parts Yard are not compatible. I didn't count the splines, but I'm sure it's the 27 vs 28. The Ridge Line hubs fit, and they're advertised to fit the 28's, but they're tall and bulky and I would have to modify my factory Lego hubcaps (Not going to do that) in order for them to fit, or just go neked, sans hub cap. I pulled the trigger and I'm going to try the cheap factory OE Knock-offs from Amazonia. They have mixed reviews, hoping those are from people that don't know their head from a hole in the ground. 

 

Chassis rubber parts that I plan on replacing are scheduled to ship in 2 weeks. Oil pressure switch ships in a week That's not really holding up getting the rest of the stuff installed though. Just me being old and worn out myself 🤣

 

Also, ordered plenty of new fasteners. A bunch of stainless 6mm x1.0 screws to attach the random sheet metal and hose stays, along with other nuts and bolts to bolt the exhaust back together. Fun Project. Very Greasy... would not recommend. But after this is all said and done, I think it's DONE for the big mechanical issues until something else fails.

Link to comment
Share on other sites

Hopefully the Amazon ones are good! I had to butcher the hubcaps to clear my Mile Markers. Came out nice enough, but a little nerve-wracking taking a wood router to old plastic.

 

I'm waiting on parts for mine too, at least officially. Haven't gotten around to installing the parts I do have yet.

  • Like 1
Link to comment
Share on other sites

On 5/5/2025 at 1:16 AM, Slartibartfast said:

Maybe you got the early 27 spline hubs? The hubs and CVs switched to 28 spline between '89 and '90. Don't think I've ever seen a Ridge Line hub.

 

Hopefully that's the last speed bump to it going back together!

Just realized I mis-spoke the brand of the locking hubs I have on hand... It's Rugged Ridge. Sorry for the confusion....

Link to comment
Share on other sites

Latest update:

 

I got MOST of the parts on the chassis re-installed last night. Nothing is tight. Will have to lay under it for a while tightening up all of the fasteners. All that I have left on the floor of the garage is the front sway bar, front drive shaft, Crossmember with torsion bars, and a short piece of exhaust between the Y-pipe and Catalytic converter (O2 sensor will have to get plugged back in), and routing and securing of cable/wires. Now that I write it down, that's quite a bit of work left....

 

And ofcourse, there is the interior which hasn't been touched, and all of the oil that needs to go into the engine and transmission. Lots of little simple stuff, but it all adds up... 

 

One thing I will say was a heck of a LOT easier to do was to install/tighten back up the drivers side exhaust without the front axle installed.

 

Also. The starter was also easier to install without the passengers side exhaust installed....

 

Everything, I mean EVERYTHING, is interference on these things under the hood if you're looking for some room to work!!  

 

I would even consider the front axle being interference to the transmission. There are a couple of bolts that I feel would have been almost impossible to install with the axle in place.

 

I don't think I was doing it wrong, but I couldn't even see the top bolts of the transmission when I was putting them in. It was MOSTLY by feel.

 

So... I think that's going to be it for this thread unless someone wants to add to it 🙃 

 

 

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...