So I think I have a rear main seal leak but I am not 100% sure. I have replaced the oil pan gasket, value cover gaskets, oil cooler gasket, and oil pressure sending unit/switch. The mechanic I have taken it to has replaced the rear main seal and oil pan gasket (because I was sure I messed it up). If I clean the oil off of the bell housing and oil pan, there is no oil dripping from the truck. If I start the truck and let it sit for awhile, I can see oil seeping off one of the bolts on the starter. As soon as I drive it for any amount of time I will get a small set of drips under the truck. It looks like it is coming from both sides of the bell housing (dripping off the starter and oil filter). I really don't want to have the rear main seal worked on again, but at this point, I don't know what else it could be. Any thoughts?
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HOW TO KNOW rear main seal is LEAKING
- Thread starter cdow1389
- Start date
May be better to post this as a new thread. Also, how long ago were all the seals replaced? Not to sound like an not a very nice person, but you said YOU replaced the gaskets, then had tech replace the RM and OP because you may have installed incorrectly. This happens to all of us, don't beat yourself up. I have screwed up more gaskets than I can count. There is a possibility you are leaking oil from the back or the valve covers, or the rear main. Either way, I would have a good tech take a look at it. Pony up the dough this time. Or you could always invest 8 bucks for an aluminum drip pan, quarters for the car wash, and a couple quarts of oil (you should already be keeping a couple in truck, there's plenty of storage).
old skool
Full Member
I had a leak in the same area that you mentioned. Before changing the oil pan gasket, I made sure that it wasn't coming from any place higher than that. I was hoping it wasn't the rear main oil seal, which it wasn't. After replacing the gasket, it still leaked in the same area. I didn't have a torque wrench when I tightened the bolts, so I guess I didn't tighten them tight enough. Went out and bought a torque wrench and tightened to specs, and no more leaks.
In fall 2019, I replaced oil pan gasket, because it seemed doable and I was hopeful it would address the issue. March 2020 intake manifold was cracked in multiple places, so the shop fix manifold (since I don't weld and bolts were broken off) and replaced rear main seal. March 2020, a few days later engine is misfiring and still leaking, shop replaced oil pan gasket at the same time. The leak seems to have slowed down but still present, summer 2021 I replace value cover gaskets. Sept 2021, I replace oil pressure switch. Oct 2021, I replace by-pass cover gasket. My thoughts are that this entire time the truck has really never stopped leaking and the rear main seal should not have failed within this time frame. The aluminum drip pan may be the solution at this point since I don't want to invest in a lift, transmission jack and super long racket extensions to remove the transmission.
I guess I could get a torque wrench to check the oil pan, but if the shop didn't torque the oil pan down, then I wonder if they didn't torque the rear main seal plate down either.
2003LANCHE
Full Member
- Joined
- Oct 3, 2021
- Messages
- 9
Get a torque wrench and tighten it down, hope it works.
Agree. Go through and make sure everything is torqued. Next step would be to clean the engine extremely well, then add some oil dye. You will need a black light style light and some yellow glasses, they sell kits at your local parts house. Run the truck and check for leaks religiously. The oil will now glow under black light because of the dye, this method is very useful finding oil leaks.
So I got a torque wrench, checked the oil pan bolts and they were fine. I backed out the bell housing bolts to tighten them down to 37 ft lbs and one of them does not seem to grab/tighten down. Ugh, so is there something I can do to get it to tighten down?
2003VAAV
Full Member
Thread inserts, they work great. Replaces old threads with stainless steel insert. Pretty easy and holds as good or better than original threads. Another option that may be easier but one I have never tried is thread repair epoxy. There is a kit, basically and epoxy putty like JB Weld but it comes with a releasing agent. You put the epoxy in, coat the bolt with the release agent, screw in the bolt and let dry. The remove the bolt, clean and replace and torque as needed.
TFjed
Full Member
What was the torque specs on the oil pan bolts?
Edit: Never mind, found them and the specs for about everything else I needed on one site. I'll include the link for any that happen upon this thread in the future.
2002 Chevy Avalanche 5.3L Engine Torque Specs| Chevy Specs
avalanche 5.3L engine bolt torque specs, common problems and repairs. Cylinder Head Torque specs, timing chain installation, manifolds torque specs, engine assembly.
chevy-specs.com
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