1994 GMC Sierra transmission

SECHMACHINE

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1994 GMC SIERRA
4.6L
V6
4WD
AUTOMATIC
200 MILES

94 gmc 4wd 1500. Purchased about 3 months ago. No leaks. Ran it in 2wd until a week ago. Used the 4wd hi gear and after I switched back noticed that it leaked trans fluid, 1 quart, and after the vehicle warmed up a bit it shifted up to the overdrive gear. I put trans fluid in it and still shifts the same. Not leaking trans fluid anymore but only ran it a few miles. Does this ring a bell?

Tuesday, December 2nd, 2014 AT 6:15 AM

3 Replies

HMAC300

MECHANIC
48,601 POSTS

Where does it leak fluid out the trans or front seal of tcase which may be the problem.

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Tuesday, December 2nd, 2014 AT 6:42 AM

SECHMACHINE

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2 POSTS

I think the transfer case but I cannot see a leak. Both a little wet. Is that front seal easy to fix? I am a decent wrench turner.

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Tuesday, December 2nd, 2014 AT 6:55 AM

HMAC300

MECHANIC
48,601 POSTS

There are 5 different tcases but the seal thing is pretty much the same, pull driveshaft, and yoke pry out seal and replace. Make sure to see if groove in yoke may need an oversize seal with a sleeve on yoke to fix it.

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