Loud pop then truck hardly moved

JSEL1

MEMBER
2002 GMC SIERRA
0.6L
V8
4WD
AUTOMATIC
150,000 MILES

Was sitting at red light, light changed, I pushed gas and a loud pop came from under the truck. Truck wouldn't hardly budge. I had to reverse and max out rpm's to get vehicle to move backwards out of intersection. After getting clear of traffic I tried moving forward and had the same issue, I had to floor it to get it to move and it only got up to 15 maybe 20 mph. I limped it home full throttle almost.

My truck is a 1500 extended cab.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Welcome to 2CarPros.

Based on your description, it sounds like it is related to the drive line (trans, differentials, transfer case, driveshaft u-joints) or something may have come apart in one of the rear brakes.. What I need you to do is safely lift the rear of the vehicle. Make sure to block the tires so the vehicle can't move and place it in neutral. Are you able to turn the wheels?

If you can turn one and not the other, suspect a brake issue which will require you to remove the wheel and inspect the brakes. If neither wheel turns, I need you to remove the drive shaft and see if the wheels can turn. If they can't, the problem is in the rear differential.

Here is a link that shows how to check universal joints:

https://www.2carpros.com/articles/how-u-joints-work

Do this and let me know the results. At that point, I will have a better idea what needs done and can explain how to do it.

Take care,
Joe