stemmyV

Model: GMC 89

Transmission: MANUAL 5 gear

I was cruising down the at 65mph and came upon a small town I had to stop at a redlight and couldn't get into 1st gear I had to take off in 2nd and my truck barely started moving. After that I turned around to head back home since my vehicle was screwing up I was doing about 50mph and the rear tires locked up like I just hit the emergency break, barely avoiding flying into the ditch, I barely got to the shoulder lane. My truck would not move. I could start the truck when i held the clutch down but if I let my foot off the clutch it would shut off like i was in gear but the shifter was in the "neutral" position.

Any idea what it might be? How can I have my truck towed if the rear wheels are locked up?

Bullydawg

iTrader: (7)

Does your rear diff have a leak by any chance? Need more info... Is it normal that you can't get the car into 1st?

stemmyV

it started getting dark and i couldn't see under the truck very well for any leaks. I did have trouble getting the truck into first once before and it seemed like it was after i was cruising in 5th for awhile so maybe it was getting too hot or something. after the rear wheels locked up and sent me close to my death i could smell burning, not sure if it was from the tires skidding on the pavement or if it was from the transmission or something.

TreeFiddy

Something's broken in the tranny, and jamming up the input shaft. I had an old Datsun do that once - second gear shattered and fragments jammed up other stuff, luckily was barely moving at the time.

You might have to disconnect the tailshaft at the diff, and tie it out of the way to tow it.

89rs454

Well to help you narrow it down it's either the Differential or transmission, have you ever checked the fluid in your 5 speed usually known as gear oil? Or differential? Usually the gears would break before locking up the rear tires unless it's just in a hell of a bind from a catastrophic failure.

big gear head

Don't know what truck or transmission you have, but the T5 has a reputation for welding 5th gear to the shaft. My S10 did this once. The pilot bushing went bad, causing the input shaft to run at an angle, which allowed the main shaft to run at an angle and put excessive pressure on the 5th gear. This caused the gear to run very hot and weld it's self to the shaft. When it did this I was in 2nd gear and the transmission completely locked up, which locked the rear tires. I was able to hit the shifter and get it out of 2nd, which allowed the transmission to turn again, but the transmission was for ever in 5th gear. It's hard to take off in 5th gear. My truck is a 4X4, so I put the transfer case in low and was able to get off the road.

TreeFiddy

Figure it's his tranny rather than the diff, because it's locked up in neutral as well.

89rs454

Yeah, That's what i say.

91phoenix

iTrader: (5)

I had something similar happen to me in a Ford w/ a 4sp granny. Driving in 4th it locked up and I went sliding. When I stopped I found that in 1st or 2nd it was locked up. In reverse it worked fine. I had to drive home in reverse that Christmas Eve. This happened without my having a hand on the shifter.
After the reverse drive to my house it finally came out of reverse.
Either in two gears at once or something internal in the tranny caused it to lock up.