Replacing transmission output seal with transfer case in situ?

[Tim Smith]

A question for the more experienced folks here.

As I continue along the path of fixing various leaks on the lightweight, it became obvious yesterday that I need to replace the transmission output seal. The question is, can I replace the output seal without pulling the transfer case? If that is possible, is it worth it or is it just easier to pull the transfer case to do this job? Any other gotchas?

The output seal on the parking brake was a bear to get out. Lots of chiseling and profanity. I hope the transmission seal isn't as difficult.

Cheers,
Tim

[daveb]

well for all the gearboxes I've had apart and rebuilt I can't recall yay or nay on that one. but it sounds like you need to invest in seal puller...

A question for the more experienced folks here.

As I continue along the path of fixing various leaks on the lightweight, it became obvious yesterday that I need to replace the transmission output seal. The question is, can I replace the output seal without pulling the transfer case? If that is possible, is it worth it or is it just easier to pull the transfer case to do this job? Any other gotchas?

The output seal on the parking brake was a bear to get out. Lots of chiseling and profanity. I hope the transmission seal isn't as difficult.

Cheers,
Tim

[Tim Smith]

...but it sounds like you need to invest in seal puller...

Yet another tool I didn't know exists. Any links to some that you would recommend?

[gudjeon]

I would say there really is no easy way around this one. The transmission could be left in place and the transfer case removed. To do this the mounts and parkbrake/speedo stuff is removed. Now for the fun part. The trans output to the transfer box gear needs to be removed. This is accessed from the PTO cover on the upper potion of the transfer box. The main drive gear underneath this cover is held with a special locknut. From memory, it might be left handed thread. This needs a special lugged tool. It is available or one could be fabricated. Once this gear is out, you can remove the additional hidden bolts that help hold the tranny to the transferbox.

Removal of the transfer box can be made and access to the rear tranny seal is now granted to you. I am relying on memory so someone can add details if I missed something. I have only replaced these upon rebuilding the transmission.

Good luck

This job is not one I would want to do every day.

[BackInA88]

I'm not 100% sure but I think you can get it out without removing the t-case.
You have to remove the big rear cover, the top cover.
You can use a drift and hammer to remove the keyed nut retaining the transmission output gear, just don't forget to bend up the tab on the locking washer.
Slide the gear off and the tubing spacer behind it.
Now you maybe able to use a big screwdriver, crowbar or the special seal pulling bar to get it out.
Either way it is a pain working around the output shaft.

http://www.tooltopia.com/index.asp?PageAction=VIEWPROD&ProdID=5109

I remember reading on the series2forum about this being done.
And looking at the trans and t-case on my basement floor it looks doable.

Steve

[Tim Smith]

Thanks for the product link and the notes folks.

I agree, looking at it (with all the oil dripping on my face while I'm under the truck swearing at the thing) this does look doable. Not sure if it's worth the trouble but I'll report back to the forum when I get to this one.

The requisite seals and gaskets are in the mail now, so maybe I'll get to this before the end of the week. Time permitting.

Cheers,
Tim

[Tim Smith]

So yesterday I finished replacing the seals in and around the transfer case and wanted to update this topic in case any one is interested in the future.

Can you replace the transmission output seal with the transfer case in situ? Yes you can! In fact, I couldn't believe how easy it was compared to some of the other seals I was replacing. Maybe I was lucky.

Basically all you really have to do (if this were the only seal you were interested in) is:

• Pop the parking brake assembly to make room for the intermediate gear shaft
• Pop off the bottom pan
• Pull the rear cover (or overdrive if you have one) and input gear
• Pull the intermediate gear to give you some working room
• Pull the fiddly seal protector off
• Then with a screwdriver or a punch, drive it into the side of the seal so you've got good leverage to pull it out
• Get a wrench or suitable device that you can use to create leverage and slide it between your screwdriver and the transmission side of the transfer case
• Say a small prayer to your rover god and then pry the seal off

I have to say, it was real easy to pull compared to some of the other seals that get a little more of the environment beating against them.

In the end, I don't think this seal was the main issue with my truck. The intermediate gear shaft had come dislodged from it's holding clamp and was actually sticking out about 1/8 of an inch from where it should have been. This means, among other things, that the seal was not making contact with the transfer case opening but instead was sitting out in the open doing nothing!

Fixed that and all the other seals I could while i was down there and it seems to not be leaking any more. Ive had a few 20 minute highway runs and so far so good!

Two other notes. The oil that came out of the transfer case had lots of grindings in there. Not good but now with the fresh Lucas oil it is super quiet again. Which is great on the highway!!

Now what is that new rumble that happens when I let off the throttle...

[daveb]

wear in one of the output shaft bearings. wasn't happening before?

Now what is that new rumble that happens when I let off the throttle...

[Tim Smith]

wear in one of the output shaft bearings. wasn't happening before?

Thanks daveb. I'm going to start a new thread on this because I'm getting the feeling that this is actually the diff.

[daveb]

pull driveshaft, run in FWD. see if ti goes away. my 88 did that too but only in front wheel drive with the rear axles out (500 miles back from ottawa)

my other friend had one that did it in 2wd on the overrun like you are saying.

it went away in 4wd.

scott wickham had it happen on his S3 and changing the transfer case didn't change. so actually i guess maybe it IS the diff.

Thanks daveb. I'm going to start a new thread on this because I'm getting the feeling that this is actually the diff.

[Tim Smith]

Thanks for the thoughts daveb. I actually started the new thread at Scary rumble at 70. You can follow up there.

It's starting to sound like I didn't line up the drive shaft properly when I had pulled the thing apart for the new slip joint boot. My second guess is a bad UJ. Third is the diff, just because I want a 24 spline...