Car is 02 camaro ss a4 ls1 with 140k miles. At about 135k i changed stalls while in there i replaced the rear main with cosmetic seal kit around 500 miles later it went to leaking again. Dropped trans and replaced it again with a kit from a parts store. Few miles later same problem. Whats going on here crankshaft looks good no groves. Any help apreciated

 

Are you putting the seal in backwards?

 

So the first time you changed it was because it was leaking, or just because? As my "first start" was 5 years after I bought my used engine, I ASSumed it was due to age and tore everything apart for nothing. Ended up it was due to adding new sheetmetal valve covers with no venting. If you've made no other changes, perhaps your PCV system is dirty or plugged?

 

100% sure seal is in correct. Ive got a catch can setup but using the old pvc valve. Ill try to change the valve out.

 

It happens, when I dropped in my ls6 crate engine a number of years ago, that darn seal was leaking. Brand new engine. Talk about something to scream about. So out came the trans clutch exc. and a new seal went in.

My only suggestion would be get a seal directly from GM, triple check the direction your installing it, its been a while, but I believe it only goes in one direction and make sure you coat the seal in Vaseline to aid in installation to keep it from stretching/tearing.

Almost goes without saying but run the engine for a good 10-12 mins and watch the seal to make sure it doesn't leak after the install. The last thing you ever want to do is to have to pull everything apart again.

 

Did the seal you get come with the plastic ring inside it to help in install? Are you sure its coming from the seal and not leaking out of the rear cover?

There's a small possibility you have excessive thrust bearing play and the crank is walking but that's probably a long shot.

 

That's also a good point. The plastic ring to help get it right. It also keeps the ring straight.

It might have a thrust problem, but didn't he say it started after the install?

 

The way it reads it leads me to believe it was leaking before but I can't be 100%. Another thing I just thought about is if it could be leaking from the freeze plug in the back of the crank. However if that was the case I wouldn't think it would take 500 miles to show up unless it's a small leak and is taking a while to show up on the outside of the engine.

 

This is where I'd look next. Also a cheap gasket directly from GM -- and not much more work if already in there to do the rear main.

 

Maybe its misaligned?
http://www.saccitycorvette.com/Timin...nmenttool.html

 

Replace the rear cover. It's only ~$50 from GM. Comes with the gasket and new hardware. Don't screw around with just the seal, or some gimmick tool.

 

In defense of the Sac City tool, if you're someone who works on LS motors often, then the tool will pay for itself in time saved.

 

Thank you demonspeed!

 

Bump for a dumb question:

If replacing the entire rear cover as an assembly, is an alignment tool necessary?

I've got an LS2 dropout with 71K miles. I don't see any sign of seepage from the rear seal but I feel like it would be prudent to replace while it's so easy to do so (while it's not in the car).

This is my first LSx and I'm just a bit concerned about getting the front cover, oil pan and rear covers properly installed and aligned (I need to swap oil pans and I'm swapping cams, so the front cover will be removed as well).

TIA.

Tipsy

 

I replaced only the seal in my LS1, not the whole cover. No problem getting it back together with no special tool.

You need to install the oil pan and snug up the bolts from the oil pan to the rear cover before tightening the bolts which hold the rear cover to the block. Then finish tightening the two bolts between the oil pan and the rear cover.

If while snugging up the bolts between the pan and cover, the rear main seal looks like it is off center from the crank and the seal lip is pulling off the crank surface, then stop and figure out what's wrong.

I very gently went over the crank sealing surface with 600 grit sandpaper and smoothed it out before installing the seal/cover. I did clean the crank up very well after sanding and added some oil to help the seal slide on. It's really a somewhat simple job once you think through the process.

 

There's a lot of mystery floating about on this rear seal thing, so take it from a guy who just did it and leaned it myself. You'll hear all sorts of things about it and the rear cover from people who just repeat what they hear.

Do the cover while you do the seal. Fel-Pro makes a kit for $23 dollars that comes with both, and the plastic ring. There is a certain side it goes on, mark it.

Take the rear cover off. Use a brass brush or something like it to clean the block surface and cover without hurting the aluminum. Clean very well inside the sealing surface for the rear main on the cover.

Install the rear cover back on the motor, using a tiny, TINY bit of motor oil to lube the surface. Not much. Snug down all the bolts just barely finger tight.

Snug the bolts enough where the cover can move a bit, but isn't sloppy. This is important. Install your rear seal with ever so small amount of oil around the outer diameter. Do not remove the whatever grease on the inside of the seal. Some say it's a Teflon super something, I don't know, I just used it.

Using a round PVC, flat block of wood, whatever you have to do it, mount the seal by hand first, then gently tap in either the whole thing if doing with a circular tap, or side to side if using a block. Keep it as even as ever possible, the seal should be a tight fit. As soon as the seal catches on the crank, the plastic ring falls off. Good.

Tap the seal in until it sits flush with the cover. The seal is going to center the cover where it wants it to be around itself and the crankshaft. You can wiggle on the cover to check that, I don't recommend it. Now tighten down your rear cover, then do your oil bolts. If you do oil pan bolts first, it tends to pull the cover down and put stress on the seal. Then it leaks.

Now drive it. I'm not telling you I did it the super right way. I'm not claiming I am superior to the guy who's doing it different, but I tell you this. I did it, learned how to do it as I went, treated it like a delicate seal, and it worked. Take your time, pulling a tranny sucks. I have no leaks where it used to drip 30+ drops a DAY, especially when I had crankcase pressure. Now it doesn't. A thousand miles later on a car that's started multiple times a day has shown no leaks, which is more important that how many miles, the constant build up of crank pressure and letting it sit on the seal makes a problem more apparent.

Just my .02.

 

My problem ended up being a bad pcv valve. Changed it and all the lines and hasnt leaked since.