Rear Axle Seal Leak

[Gratefuldiver]

Went to a T&T auto x last Sunday and noticed that after about 10 runs that I had a drip from my rear end axle seal. It only dripped a couple drops right after a run. Hasn't leaked since.

You think this is a sign the seal is failing or was it just the g force of the back to back to back runs? It's a 66 GM 12 bolt in a 72 GTO

[dontlifttoshift]

Check your vent. If pressure builds it will push out somewhere.

[Gratefuldiver]

Ok so I looked and there is no vent on my rear LOL, Ive looked at some old post and it looks like it should be on the pass side on top of the axle? There is what looks like to be a hole there but not vent. Id have to assume its pluged if its not leaking there. I didnt have time to really get a good look at it. Im going to take it over to a buddies house Sat and put it up on his lift to get a good look. Is there a reason someone would plug the vent hole? Again its a 12 bolt out of a 66 Chevelle

[rrelco]

Went to a T&T auto x last Sunday and noticed that after about 10 runs that I had a drip from my rear end axle seal. It only dripped a couple drops right after a run. Hasn't leaked since.

You think this is a sign the seal is failing or was it just the g force of the back to back to back runs? It's a 66 GM 12 bolt in a 72 GTO

i am running a 12 bolt in my Elco and had the rear end rebuilt a few years ago and it just started leaking, i called the shop to ask if this was something that will be going on and on and he did say that these rear ends are not designed for auto cross abuse. and that most likely these will need to be replaced. unless i go with the full floater. i just replaced mine 10 each seal plus my time.

[Gratefuldiver]

No input on where I should be able to find the vent on the 66 rear end?

[a67]

Usually located on the top right of the center section. Stock are plastic and is likely gone. Here is a sample replacement type:

http://www.jegs.com/p/Competition-Engineering/Competition-Engineering-Rear-Axle-Housing-Vent/744451/10002/-1

Will need to at a minimum tap the hole for it. The stock ones just press in.

Bob.

[MonzaRacer]

For a vent go to junk yard find a truck with one on a hose that clips too frame, remove cover, drill, tap and insert a brass barbed fitting.
Honestly if it keeps going on, a worn bearing and axle WILL leak.
And also dont forget c clip type axles can move in and out.
I actually wound prefer to have an axle with a clip eliminator that uses a snap ring, biggest issue is stress can break axles and the snap ring groove would be weak spot.