Rear Main Seal

[Kenneth]

I am looking into chaning my rear main seal on my 94 with the engine still in the truck. Can anyone give me an idea of how hard this project will be. I have done rear main on an engine stand, but not with the engine still in the truck. I looked at having a shop do it, and $400+ does not sound good to me. I am going to try and get a couple of my auto buddies at school here to give me a hand on a friday afternoon and saturday, and I just wanted to know from those who have it done in the truck, what I am getting myself into.

Any tips would be appreciated. I looked up the job on both mitchell and Alldata, so I have an idea, but those programs don't talk about tips or shortcuts, etc.

I appreciate all your guys' help.

[trbankii]

Just did it the other day. The rear main seal was the least of the problems - it just presses in place. No problem doing it in the truck.

The hard part is that you have to remove the transmission - and transfer case if it is 4WD. Then clutch and flywheel if manual or torque converter if automatic.

I was in there to replace the clutch, so did the rear main seal since it was exposed.

[AKMark]

Isn't it a two piece like a 6.2?

I've done a Jeep 4.0L two piece before with very little work.

Pull oil pan, pull rear main cap. With a punch be very careful not to hit the valley the seal sits in. Tap with mallet till the seal end is exposed on the other side. When it's accessible put a vice grips on the exposed end and pull it out. Carefully press new one in place, replace side on bearing cap. Put everything back together, and away you go.

Mine took about two hours.

[Hubert]

[QUOTE=AKMark;239166]Isn't it a two piece like a 6.2?

QUOTE]

Nope its one piece and you have to take flywheel and back off to gain access.

[AKMark]

[QUOTE=AKMark;239166]Isn't it a two piece like a 6.2?

QUOTE]

Nope its one piece and you have to take flywheel and back off to gain access.

That stinks

[trbankii]

Single piece on my '93. Was it that the two-piece carried over to the first 6.5s? Or that the single piece was in the late 6.2s? I seem to recall some crossover like that or something...

[AKMark]

I've torn apart a 82 and 85 and a 91 6.2, all three were two piece.

[Kenneth]

Thanks for all the info! From looking at Alldata and MItchell and talking to the Gm dealerships it's a 1 piece seal. My truck is a 2WD with AT. Looking at my school schedule, I may not get to the truck until later this fall. I do have a couple other questions though. Do you have to drain the transmission before pulling it? I ask because I pulled an TH400 a while ago and the torque converter moved a little and i split a bit of fluid. Also, do I really have to pull the transmission, or is there enough room to just slide the 4L80E back enough to change the seal?

Thanks again for all your help.

[Robyn]

You will need to get the tranny back far enough to get the flex plate off the crank and then be able to work in there to replace the seal.

You would not have to necessarily drop it out but its gonna be in the way probably.

Best

Robyn

[trbankii]

You won't have to pull the transmission out from under the vehicle, but by the time you unbolt everything from the crossmembers and slide it back far enough to get the flexplate out of the way, you really need a transmission jack and all.

[Kenneth]

Thanks for all the info. I'll let you know how it turns out...when I finally get it done. Thanks again.