4wd problem

clwilliams · November 24, 2023

Hello all,

I've got a 2000 Sierra 4wd 5.3 litre with a push button 4wd issue. 4wd not engaging at front end. I replaced the actuator on the front diff. The lights indicate gear change and I can hear the motor. It is engaging low, but no drive at front end. In 2 high I can turn the front driveline manually, but not in 4 high. No drive at front wheels in any gear. Did I get a bad actuator? Could there be another problem?

Thanks all

BarryKH · November 25, 2023

I have not had this problem, but I would start by checking the axles, make sure the splines are not stripped. I would check everything I could like that before opening the differential. I seems as if the actuator motor is working, but I would be sure by having someone help me by having a hand on the actuator when you try to engage 4wd. I will try to do some research and see what I can come up with. Sorry I can't be more help.

clwilliams · November 26, 2023

14 hours ago, BarryKH said:

I have not had this problem, but I would start by checking the axles, make sure the splines are not stripped. I would check everything I could like that before opening the differential. I seems as if the actuator motor is working, but I would be sure by having someone help me by having a hand on the actuator when you try to engage 4wd. I will try to do some research and see what I can come up with. Sorry I can't be more help.

I tested the actuator before I installed it by changing from 2 high and 4 and back with the key on but engine off. Preformed as it should. As far as the axles I think I would hear something it that were the case, but worth a shot. Thanks!