Got a 99 Silverado with the 5.3 motor and when I was under the truck replacing the Y pipe and cats I noticed the the front driveshaft is locked. I had a 97 chevy truck that had the "push button" shift and when it was in 2-hi the front driveshaft would turn freely. Is the newer stuff diffrent or do I have a problem with the electric transfer case shifter. I read somewher that if the transfer case shifts incorrectly the light on the buttons change color indicating a problem. The transfer case will shift into low range and back to high but I thought the driveshaft would not turn in 2-hi??
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Needed, guru on the new 4x4 stuff!
- Thread starter GMC Truck
- Start date
My understanding is that the front driveshaft should spin by hand in 2hi, same as your old one.
Sure you aren't in "Auto"? That would lock the front diff, but not send power to the shaft.
Sure you aren't in "Auto"? That would lock the front diff, but not send power to the shaft.
Do u have auto hubs? Ive noticed that my buddys truck has them and when behind me i can see the axles spinning in 2wd at the outer u joint.
There is no "locking hub" per say on the newer IFS trucks.
The hubs are always locked, the CV shafts always turn.
Its the center section that locks and unlocks from the driveshaft.
I figued that it did everything in the tcase. I dont see how the pig itself would lock and unlock.
I say jack the front end up. Spin tires and if tge driveshaft spins its locked in the pig. If it doesnt spin its locked in the tcase. Correct?
Nope. Front thermal (early 90's) to mechanical (96+?) actuator in the front end to engage/disengage front diff.
When in "Auto" mode wiht autotrac case, front gets locked in to shaft, and tcase sends power as needed to front shaft.
I have it in 2-Hi but the shaft does not turn freely. I have been told that it will NOT turn because of the design of the transfer case. The only diffrence between 2-Hi and AUTO is the computor monitors for wheel spin in auto and locks the front diff if needed but in 2-Hi the shaft still spins but the computor is not looking at the wheels for slipping. Makes sence but i'm not sure??
If thats the case, thats a 99+ change, and i have no idea.
But the above i stated is correct for 88-99(92-00 for suvs).
But the above i stated is correct for 88-99(92-00 for suvs).
I agree! I had a 1997 K1500 and when it was in 2-Hi you could reach under and spin the driveshaft no problem. The tech told me that it is still that way on the 243 transfer case but I have a 246 and it always turns the front shaft. I guess the trucks with the 243 can turn the shaft in 2-HI. He said it has something to do with the motor that operates the transfer case?
I checked my 2001 2500HD and I can turn it! But it don't have the switch with "auto"!
