I have a '99 GMC 8500 set up as an ag spreader truck. Cat 3126 with a MT 653 Allison. Transmission PTO runs the spreader. I was spreading, stopped and backed around a corner, and when I put it in 2nd, it just stood there and reved the engine a little. I have reverse in reverse, reverse in neutral, and seems locked up in the forward gears. I dropped the pan and found 3 small pieces of broken off metal. Are there any tests I can do on the tranny or things to look for short of just replacing the entire tranny? Any things to be cautious of when replacing the tranny?
Do you have the push button shift or the tee handle?
Shut it off for three minutes should reset the transmission.
Yeah, don't drop the new trans rolling it under the truck...
Tee handle shifter colson: Ouch!
The very first thing I would do is check all your grounds and clean them. There is a group of grounds that come from the tranny and goes to the transmission bellhousing. These are the first I'd check. You can also get the codes out of the tranny by pushing buttons on the shift column depending on which one you have.
If you look on the base plate on your tee handle there is two small buttons(One small enough you have to push with a pen ) push both at the same time will pull up the codes , such as D1 2201 and than push the bigger button and D2 with a code number will come up and so forth.
and if the easy stuff fails here you go http://ww2.justanswer.com/uploads/H...ison_transmission_md3060_trouble-shooting.pdf
Thanks for the link grandpa. Unfortunately it doesn't cover the MT series, and I haven't been able to find a download that does.