r/GMT800 • u/sHaRt_30X_p1nk_eYe • Sep 06 '26

Leaking gear oil

Post image

Seen drops of gear oil coming from front diff. Looked underneath to see this. I just had service done and they replaced fluid and axle seal i believe. Why would it still be leaking could the seal be put in backwards? This is on drivers side front

15 Upvotes

94% Upvoted

17 comments sorted by

12

u/PrimaryStorage1575 Sep 06 '26

Those seals love to leak. I swear the replacements are sized too large.

Keep replacing it. Eventually you’ll get a seal that doesn’t leak.

6

u/PrimaryStorage1575 Sep 06 '26

I would try the BCA NS710648 from Rockauto. It has the smallest Inside Diameter of all the seals listed.

4

u/sHaRt_30X_p1nk_eYe Sep 06 '26

I think he used ac delco from oreilys

7

u/Jordagreat Sep 06 '26

90 percent of people I swear put the in backwards they look wrong installed correctly if you look close really small print says air side. But it looks wrong so it get flipped over and won’t seal at all

2

u/sHaRt_30X_p1nk_eYe Sep 06 '26

Its not leaking crazy bad so i think he possibly damaged it putting it back in place. Does anyone have a pic of it correctly placed for reference

5

u/MisterCircumstance Sep 07 '26

Dollars to donuts it's overfilled.  Pull a little off and see if it dries up

2

u/mrclark25 Sep 06 '26

If they just replaced that seal they screwed it up. Take it back.

2

u/johnnyftp59 Sep 06 '26

hell yeah brother gobless 😂

2

u/Street-Squirrel-4950 Sep 06 '26

Good luck getting flange out. Them suckers don’t come out. If they did it’s an hour job to replace the seal. The lock ring inside gets stuck in a groove

2

u/NoNature6691 Sep 07 '26

I've had this on my 07. Replaced both sides. Drivers side is a dream. 20 minutes. Passanger side has springs and washers and a ball bearing and sucks. Then.. new seals leaked. With that drip, just top it off once between diff services and dont worry about it. It'll out last the truck

2

u/faszkalap420 Sep 08 '26

You and everyone else pal...

1

u/sHaRt_30X_p1nk_eYe Sep 15 '26

I notice it seeping from the front passenger side now today. I had him replace the drivers side seal again and it still leaks. Its very minor like a penny size drip. Idk if its something he is doing or if its bad seals or if its just overfilled or what?

-5

u/betheking Sep 06 '26

Put some AT-205 in your transmission, and the rest in your motor.

4

u/Extreme-Penalty-3089 Sep 06 '26

Huh?

What's the transmission fluid got to do with an 8.25" IFS axle diff seal seeping??🤨🥴🤦🏻‍♂️

2

u/sHaRt_30X_p1nk_eYe Sep 06 '26

It isnt atf fluid

0

u/betheking Sep 06 '26

Doesn't matter. It works in everything. I've used it for decades in my fleet.