rear diff. question???

[silverhawk]

Hi Guys, New to the threads but wanted to find out your ideas of what kind of problem I might be having with my 98 6.5L Chevy 3/4 ton two wheel drive. I noticed a few drops of some type of fluid under the center of the axle at the differential every time I move the truck. Someone told me this might be an indication that I have a messed up gear problem. What do you all think?
And thanks for your time!

[Billman]

It might just be a leaking pinion seal.

[norm]

Probably a good time to do a rear gear oil change. Clean up good when you're done, esp. your cover sealing surface so you know you won't leak there - and you will see where the oil is coming from. It might not be worth fixing a small pinion seal leak, as that can be expensive. But, if it leaks a lot, that's not good either.

[bobt]

Silverhawk, Another thing to check is the differential vent tube (if your '98 has one, my '93 does). Make sure it has a continuous upward slant with no low spots that the fluid can collect in. If the fluid can't fully drain back into the differential, it will collect in the low spot and build up/be pushed out the top of the tube by pressure created in the differential, run down the tube and eventually drip off of the differential housing where it looks like you have a leak there. Take any dips out of the tube and your problem may go away.
Bob