im lost on this one, reverse, first and second work fine, but when it goes to shift from 2nd to third the rpm's shoot right up and it wont catch. my tow and haul had stopped working a few months back, and my torque converter bolts had backed out and hit the cover over the rear main seal, so i had to pull the tranny and get the broken bolts out and replace the rear main seal and cover, i dont know if i could have damaged something in the process. after fixing the converter it worked fine for about 10k miles. where do i start?

00 gmc yukon, 5.3l 4wd. any help would be greatly appreciated

 

Could be clutches or a shift solenoid perhaps?

 

Sounds like your 3-4 clutch has failed in your unit. Its probably the #1 failure in these units from my experience. With that being said its time to have it repaired or replaced. Vince

 

where can i find a replacement clutch, and solenoid, and how hard is it going to be to be replaced. am i better off getting a diff. tranny?

 

the shift solenoid is easy as dropping the pan as far as i know.
Clutches require the transmission to be completely gone through. Odds are that when your converter bolts backed out it messed up your pump and you didn't get sufficient pressure when shifting and burned up the clutches.

 

i need to get this going asap, ive been trying to find a replacement tranny for a decent price with no luck. anyone have any ideas on where to find one in ma, or a good shop to have mine fixed at?

 

I had the exact same thing happen to me. Took it to my buddy and he said for some odd reason the clutch was nearly destroyed. Said it may have gripped for the 2nd gear but not for 3rd. I don't know much about transmissions but he said it was really rare. I think I remember him saying something about more pressure being applied during the 1-2 shift and the the 2-3 had too much torque for the broken clutch to grasp. Good luck and hopefully its an easy fix. If you are gunna rebuild I suggest you beef it up so it is less likely to happen again.