I just discovered that my 4 wheel drive is not working in my 2002 Chevy Avalanche. I admit that I am nowhere near an expert regarding all things technical with vehicles. What we have done so far. Put it on the rack and engaged 4x4 button. Front drivetrain is rotating, but front wheels are not moving. Mechanic diagnosed bad actuator. Ordered that and discovered that is not the problem. He has now diagnosed it as something in the front drive shaft where it connects. Quoted a $1,500 fix. Any experience with this? Tips or advice would be greatly appreciated. I am new to the board so I really appreciate all the help.
4x4 Issues
- Thread starter trenthamp
- Start date
BlueWolfFab
Running Behind
- Location
- Eagle Mountain
If your front drive shaft and CV axles are rotating in 4WD then its your hubs.
No locking hubs on the chevs, so it has to be in the front diff if the transfer case output is turning as described.
Is the actuator you say was replaced the one that is attached to the front diff? If so, it seems you may have a serious problem in that diff. Essentially, that actuator just engages the PS CV axle to the innards of the diff, then the spider gears differentiate the individual speed of the wheels, so at least one wheel should be turning. If not, something is wrong inside the diff, and it would probably make terrible noises.
Another possibility is there's something amiss with the transfer case thinking it's in the "auto" (I'm assuming it has that option) setting and not applying the power to the front.
There's also the possibility the t-case has defaulted to the neutral position that some have. But if that were the case you wouldn't be able to go anywhere.
Is the actuator you say was replaced the one that is attached to the front diff? If so, it seems you may have a serious problem in that diff. Essentially, that actuator just engages the PS CV axle to the innards of the diff, then the spider gears differentiate the individual speed of the wheels, so at least one wheel should be turning. If not, something is wrong inside the diff, and it would probably make terrible noises.
Another possibility is there's something amiss with the transfer case thinking it's in the "auto" (I'm assuming it has that option) setting and not applying the power to the front.
There's also the possibility the t-case has defaulted to the neutral position that some have. But if that were the case you wouldn't be able to go anywhere.