Rear Main Seal

[West 1]

10 years ago I installed the Heavy Duty Tranny cooler. Made by Derale I believe, sold under the B&M tranny cooler line through Summit, design was identical to the factory cooler but is twice the size. That was 10 years ago, not sure they are still sold at Summit you would need to check. In 10 years this truck has only gone 30,000 miles but at least half of that was towing miles.

 

[West 1]

Got the tranny and transfer case back in, I had pulled the front exhaust system, torsion bars, drivelines etc so going back together was still a lot of work. I ended up not pulling the intake manifold and just did the top bolts with a 3' extension and swivel sockets. The two top bolts and the brackets at the top took me about 2 full hours to get back in. Just no room and hard to get it all in properly. My Yukon has the dual battery option like police vehicles and the extra battery wire going to the starter added a lot of extra time. I bet I wasted 2 hours getting that all hooked back up also. All good now, NO LEAKS finally. Oil pressure is perfect.

I do have floor jacks, a transmission jack, bottle jack but no lift this was all done in my garage with the truck on jack stands. Glad it is back on the road without leaks.

 

[S33k3r]

Got the tranny and transfer case back in, I had pulled the front exhaust system, torsion bars, drivelines etc so going back together was still a lot of work. I ended up not pulling the intake manifold and just did the top bolts with a 3' extension and swivel sockets. The two top bolts and the brackets at the top took me about 2 full hours to get back in. Just no room and hard to get it all in properly. My Yukon has the dual battery option like police vehicles and the extra battery wire going to the starter added a lot of extra time. I bet I wasted 2 hours getting that all hooked back up also. All good now, NO LEAKS finally. Oil pressure is perfect.

I do have floor jacks, a transmission jack, bottle jack but no lift this was all done in my garage with the truck on jack stands. Glad it is back on the road without leaks.

Just wanted to give you kudos for soloing this WITHOUT a lift. That, and ask you if you could come help with a few projects I have...

 

[West 1]

HA, not signing up for any more projects like this. Still upset about how long it takes to hoist the tranny into place using a tranny jack, in the old days we just bench pressed them up into place and got it in place in a few minutes. Those days are behind me so the new methods are much slower. But it is done.

 

[S33k3r]

HA, not signing up for any more projects like this. Still upset about how long it takes to hoist the tranny into place using a tranny jack, in the old days we just bench pressed them up into place and got it in place in a few minutes. Those days are behind me so the new methods are much slower. But it is done.

Such is the price for living a long life; or a short time, overly enjoying your life...

 

[alvocado]

Adding on to this thread after changing my oil pan gasket twice this week and still seeing a leak. I thought I didn't get sufficient RTV in the block corners so I dropped the pan a second time, installed a new gasket and followed the factory spec on RTV bead size. I can see RTV squeezing out and allowed it to setup one hour before torquing the bolts, set overnight before filling with fluids, and still have a 3" oil spot after driving it for a day.

It looks like the leak is coming from the passenger side area near the pan and block interface. I can see some oil residue about an inch above the corner of the oil pan at the trans bell housing. Crankshaft sensor is bone dry above the starter. The rear main seal had very minor oil residue on it but no drips in the bell housing below the seal.

This is making me question if the leak is coming from the crankshaft seal cover gasket on the passenger side of the cover, dripping down on the outside of the bell housing with a small amount dispersing inside the housing. The majority of the oil is running down on the outside of the bell housing. I ran the truck with UV dye for a few weeks originally and the oil pan gasket was leaking. I didn't see any dye residue inside the bell housing and only got fluorescence on the pan and outside of the bell housing - nothing around the rear main seal.

Appreciate any input from those who've had the crank cover leak in hopes of confirming the source.

 

[89Suburban]

Could be running down the back of the block from the back of the valley cover/VLOM. Also could be from the back of the valve cover gaskets.

 

[alvocado]

Could be running down the back of the block from the back of the valley cover/VLOM. Also could be from the back of the valve cover gaskets.

Everything looks dry up top and the rear of the covers are dry. Those are visible from below. I changed the oil pressure sending unit a few months ago and that is completely dry as well.

 

[alvocado]

I have parts on order to tackle this and aside from preparing mentally to do it on jack stands like @West 1 , I have a question. The shop manual references uses a locking tool to hold the torque converter in place. My TC was replaced in Jan with a trans rebuild so it won't be coming out. Is this tool necessary or can the TC be kept in place without it?

 

[West 1]

I just noticed your question. If the tranny stays pretty much level the torque converter will stay put. Before bolting it up make dang sure the torque converter is fully engaged with the tranny shaft. As you install the converter you have to support and spin it into place. Sometimes it takes many revolutions to get properly set on all the tranny splines. I think there are 3 splines that need to be engaged. As you spin and support the converter you will feel it engage and slip back a little at each spline connection.
I suspect the tool you are mentioning will hold the converter in place so it can’t slip forward off one or more splines? That would be nice to know it is in place before bolting it up.