1994 Chevy Truck front seal leaking

MAYBEJEFFREY

MEMBER
1994 CHEVROLET TRUCK
V8
4WD
AUTOMATIC
190,000 MILES

Hello. I recently had the front seal go out in my transmission. I pulled the transmission myself and replaced the seal. It worked great for about 2000 miles or so with no leaks but last night I noticed that big red puddle under the truck and sure enough, there was a steady drip from the front of the transmission when the engine was running. This is the same way it failed the last time. One day, no leak at all. The next day it was dripping steady and leaving great big puddles. Otherwise, the trans. Works flawless. It shifts nice and firm, doesn't slip in any gear. Pulls a trailer with no trouble. I've always kept the fluid changed and It doesn't look or smell funny now. It has the 4L60E transmission in it.

1 Reply

MMPRINCE4000

MECHANIC
8,548 POSTS

There may be a small sharp nick on the convertor shaft, causing the seal to fail. There is also a small round spring on the seal called a garter spring, if it came off, it will leak. It is best to use the correct seal driver to install seal, it expands the spring and prevents the spring from coming off. Also be carefull not to whack the seal too hard when installing.

Unfortualtely, you will have to remove trans again and replace seal. Look for any surface nicks on convertor shaft that could cut seal, or replace convertor. You can usually remove small surface imperfections on the convertor shaft with emery cloth.