Rear Main or Pan Leaking?

[Tooth Fairy]

How can I tell/find the difference between an oil pan gasket leak and the rear main leaking. I know the pan leaks, but, is there anyway to tell if the rear main is out too?

I don't have the LX450 here. It's in CO and belongs to my mom. She is driving it out here this weekend for me to do the work sio I just wanna see if I can figure this out from here. She is willing to take it over to Christo to have him check it out too.

Thanks, Butch

 

[landtank]

I think you can pull the tranny inspection plate and peak up inside. But it's most likely the pan seal.

 

[landtoy80]

99 out of 100 it is the pan to rearmain seal retainer leak.
From all the work C-dan did to get the upper oil pan off, I don't know which is harder to do, dropping the oil pan or tranny? I did the tranny, twice

 

[landtank]

The pan is not that bad. It just requires the engine be raised off the mounts.

 

[landtoy80]

The tranny is not bad. It just requires the tranny to be dropped.

You need the REAL tranny jack to do the job though, the tranny jack that adapts to the floor jack won't work.

 

[landtank]

I pulled the tranny/transfer off my 60 witout a jack. What an awkward PITA assembly that was.

 

[landtoy80]

You can drop the t-case with the tranny jack adapter. I have done that several times.
Even with the big tranny jack its a PITA. The tranny and t-case together is rather long and heavy.

 

[IdahoDoug]

Consider that it may be nothing more than the rear drive shaft's front joint tossing grease which then thins and separates. This is a normal part of a greased joint as the excess squeezes past the seals after a proper regrease. Mine's been doing that since new and I've had numerous people tell me it's a pan leak. Not. I suspect a lot on this list have paid for a pan job when a degreaser and cleaning would have revealed my diagnosis instead.

 

[Rookie2]

It'd probably best to have her take it by Slee's and let a trained eye look at it. The oil is generally going to show up at the base or bottom of the area where the rear main seal and pan arch are. Since the distance between in the arch and rear main seal is only 3/8" or so, I'm not sure how to be sure which one is leaking. If you could get your hand up there and clean the area off real good, you might be able to go the dye route, drive it briefly and see where it starts coming out first.

I went with the rear pan arch fix, still had a small leak. Switched to Chevron Delo 15w-40, and don't seem to notice much seepage lately (knock on wood). Either way, it's a lot of work. If the leak is small, I might suggest leave it be.


Rookie2

 

[scottm]

You can see the rear main with a mirror. I wiped mine off and it looked like it was coming from the rear main. $500 fixed it at a local independent wrench, no more leak.

 

[cruiserdan]

If oil is leaking at the rear main or the pan arch you should get some oil on the swaybar. In addition the bottom of the bellhousing at the lowest point will have oil on it. My pan arch was leaking and it migrated to the sway bar in time. I would wipe the sway bar down and then have oil on it again after a week or so. Mine did not leak quite bad enough to hit the ground unless I did not wipe it down monthly.

My leak disappeared when I removed the pans to get the timing cover off for my one-in-a-million oil leak My bet is the pan arch and not the rear main seal.

 

[landtoy80]

This is the rear main retainer. The leak is where the red is if its the retainer.. The pan also mounts to the retainer where the red is. The retainer is very close to the seal so it is very hard to tell where the leak is.
On mine the factory put too much sealant on the oil pan at the retainer so there was a lip of sealant that would hold a pocket of oil. It would hold about a teaspoon of oil so the leak was small and slow.

 

[Tooth Fairy]

She is willing to take it to Slee to have them check it out, which I think I may have her do before she drives it out here this weekend. [there goes wheelin' for Memorial Day ]

I looked at it when she was here last month and she had more oil underneath her '97 450 [165K] than my '93 80 with 250k on it, but, it wasn't leaking bad enough that I felt anything needed to be done. I told her to keep on driving it until it started to drip onto the garage floor... it started to drip onto the garage floor.

The dealer had given her a list of stuff to be done and other than the axle service they wanted $950 to do the rear main. I was planning on getting to the birfs later this summer anyway.

I am very comfortable doing the work myself and it looks like she'll be out here for sure to have me do it. Plus she's gonna give me some $$ to get-ir-done.

How many hours am I lookin' at here? Any thing else I should do while I'm in there?