Rear Diff problems/leak?

[Eagle70ss]

So, I noticed there was a drop of diff fluid on the bottom side of the case and so I investigated. I drained the fluid and noticed that the diff was no longer full. The only place the was wet was around the upper fill plug and the stream that it left on the way down. The yoke seal was completely dry all the way around...I was perplexed about how fluid could be coming from the fill plug. Anyways I filled the diff back up and tightened both plugs really snuggly. I noticed after I drove it, it was doing the same thing. I cleaned the diff and put silicon around the rim of each plug and now there is no more leak. Any ideas?

[j cAT]

Originally Posted by Eagle70ss

So, I noticed there was a drop of diff fluid on the bottom side of the case and so I investigated. I drained the fluid and noticed that the diff was no longer full. The only place the was wet was around the upper fill plug and the stream that it left on the way down. The yoke seal was completely dry all the way around...I was perplexed about how fluid could be coming from the fill plug. Anyways I filled the diff back up and tightened both plugs really snuggly. I noticed after I drove it, it was doing the same thing. I cleaned the diff and put silicon around the rim of each plug and now there is no more leak. Any ideas?

the diff plugs need thread cleaning wire brush if necessary and a coating of thread sealant... not silicone sealant...use a degreaser to clean oil off threads before applying thread sealant.. i believe 15ft lbs of torque to tighten....

if this diff operated with a low fluid level removal of diff cover to inspect and clean cover magnet....if no magnet get one....

[randy78]

the plug uses plumbing threads and self seals due to the thread shape

silicone is bad

but youre only sealing against gravitiy anyways

so even bubble gum would work fine
plumbers pipe thread dope is what i use on almost any threads, including head bolts threads

it lubes and seals, to 500 degrees, and higher PSI

perfect stuff

axle oil leaks, it happens

and most ppl never check the axles and let them leak dry and go kaboom

good luck

[MT-2500]

And always check the rear axle vent and vent line for beinging pluged.
No vent will stir up leaks in it.
MT

[Eagle70ss]

Vent line? I have a vent hole that's almost directly above my fill plug(maybe a 1/4" through hole or so)...There's nothing obstructing that hole. Is that all I need to check? Anyhow I ended up changing the yoke seal and that seems to have cured the problem.


randy:
Do I get that plumbers dope and hope depot or other hardware store?

[j cAT]

Originally Posted by Eagle70ss

Vent line? I have a vent hole that's almost directly above my fill plug(maybe a 1/4" through hole or so)...There's nothing obstructing that hole. Is that all I need to check? Anyhow I ended up changing the yoke seal and that seems to have cured the problem.


randy:
Do I get that plumbers dope and hope depot or other hardware store?

you need a vent line installed,since you don't have a clue on this as it was originally go to a used car lot and look under trucks there then buy what you need to reconstruct this vent line with a piece of plastic stuck on the end of hose...if you don't you could end up with water and other contaninates and leaks from/because of that hole not properly vented...


home depot or a auto parts store will have thread sealant tell them it's for the diff fill/drain plugs.....

i use permatex thread sealant.....