2 piece Rear Main Seal Replacement
 

Hello! A few questions regarding the two-piece rear main seal. I have a 1985 TA HO with a 305 and 5 spd. Tomorrow I will be doing my first-ever clutch replacement along with flywheel, bearings, fork, and hopefully rear main seal. Most of the information online I have found is for one-piece rear main seals and if there is anything showing a 2 piece, it is usually demonstrating a replacement without taking off the transmission and only taking off the oil pan which is what I want to avoid.

I'm taking the tranny off, so can I just go about this by yanking out the 2 piece seal and replacing it by pushing the new one in (like a one-piece)? I want to avoid taking off the oil pan due to not having any experience with what it entails and since the car will be on a lift and I'll be propping a piece of wood between it and the chassis (so the engine doesn't lean anywhere it shouldn't).

All of my knowledge is stemming from Chris fix videos and before this, I've only done dizzy cap, oil changes and brake rotors.

Any advice is appreciated!

Re: 2 piece Rear Main Seal Replacement
 

No.

Oil pan must come off. Then remove the oil pump from the rear main cap, then the cap from the block. Then you can get at the seal. Although, it's usually not possible to get the upper half of it out of the block without loosening all the main bolts to allow the crank to drop a bit.

Re: 2 piece Rear Main Seal Replacement
 

:yup: not like a 1 piece at all . Have to do it like sofa said

Re: 2 piece Rear Main Seal Replacement
 

Just curious if of you have access to a hoist? I see you do!!!!
Just did another T5 the other day on F-Body (had 4 post hoist with rolling jack) and this time I tried disconnecting shifter from under. Well it worked very well and I did not have to dissemble the interior centre console. Mind you it was hard on the wrists and fingers but it worked. Reinstalling was a breeze. I'm always worried dissembling interior parts as it's old and brittle. This one was also in good shape so more nerve racking.
Just saying if it ever crosses your mind. I'm pretty sure lots of people figured that out but I could not find anything on TGO about it.

Would love to get my hands on an old 305HO T5, more like Camaro 83!!!
Cheers

Re: 2 piece Rear Main Seal Replacement
 

Didn't know there was any other way. ??? I guess you could literally tear the whole car apart, but that would uncomfortably resemble w ... wo ... wo ... [pppppuuuuuuuuuuuukkkkkkkkkkkkke] sorry, just can't quite get it to come out, dirty 4-letter swear words like that one evoke strong visceral responses sometimes...

I've posted it many times before, though not as a topic or whatever; just telling people to do it that way with a short 13mm combo wrench when giving T-5 R&R instructions.

Re: 2 piece Rear Main Seal Replacement
 

Well, well, well. I knew someone would chime in and say: WTF? Who else than @sofakingdom !!! Great to hear from you even if sometimes you can brutality answer and hurt my feelings :lmao:. I guess, TGO search engine did not yield anything on that. It was about the text book disassemble the centre console, bla bla bla. But when I hooked my eye balls on it carefully this time, I did the same WTF? The light came on. So from under it came out. I have to say though, with my T56 shoved in my Formula, there is not much space to wiggle my fingers. The T56 is way bigger. But next time, and believe me there will be next time, I'll try it.

Re: 2 piece Rear Main Seal Replacement
 

Before you install the two piece seal, check the amount of interference... Or overlap. Most new seals have too much and they over crush when you install.

Install one half in the bearing cap. Push one side down flush, measure how much the other side sticks up. Do the same for the other half. Add them up... Check against specs. I think the total needs to be below 0.1 inch but I could be wrong... It's been a while. File down until in spec.

Every time I did a two piece, it would leak... Until I learned about this crush spec. 0.05 in max on each side.

Re: 2 piece Rear Main Seal Replacement
 

Last one I did in the car, I was able to drive the upper one out and drive the new one in. In addition^^^to clearance...seem to recall recommending offsetting the seal and not installing it in-line with the split in the cap...
Attachment 458530

Re: 2 piece Rear Main Seal Replacement
 

Huh 🤔 I’ve always lined up and used anaerobic sealer on the main cap.

Re: 2 piece Rear Main Seal Replacement
 

I didn't bother to try and remove the upper on my 77 C3, the lower was a pita to get off with the cap in my hand. Couldn't imagine trying to get the upper out with the crank still there.

Don't forget a slight amount of sealer on the cap itself, flat part either side of the seal(between the pan gasket).