Chevy Truck question

[nathan_w1]

Ok, here it goes. My dad's 91 Silverado is leaking tranny fluid but the catch is that the dipstick reads full. I got under it and found a small leak where the driveshaft goes into the tranny. I guess what I'm asking is why would the level be full and be leaking at the same time?

[rabidpanda69]

it could have been over filled. How long has he had the truck? a previous owner may have over filled to compensate the leak.

[wokeupscreamin]

is the fluid supposed to be check with the engine hot or cold?

[nathan_w1]

the tranny fluid is supposed to be checked hot. My grandfather is the original owner of the truck so needless to say, we know its history and it has never leaked till now.

[rabidpanda69]

Some dodge's have to be in neutral when you check it. I have yet to see a chevy that had to, but read the dipstick to be sure....

[nathan_w1]

I'm 99.9% sure it has to be in park to check the fluid.

[caddy39]

The truck should be warmed up and the gear indicator in Park.. The part is not hard to fix. Its just the rear tranny seal. I see it all the time in the shop. Should not be too expensive..

[ENGGUY]

Well as it is used things will start to wear out. The output bearing could be wearing and letting the slip yoke move and wobble some, or it could just be the rear seal is wearing out.
It is that simple. If it gets worse it will need to be fixed.

[matts]

i have a 91 and had to replace the rear seal, take it out and take it with you to the parts store. they gave me the wrong one twice

[nathan_w1]

Thanks for all the replys. It turns out it was the seal where the speedometer cable comes out of the tranny. It was like a $20 fix.