Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
will it shift from 2 hi to 4 hi no problem ?
do you know if there are any codes set in the 4WD computer ?
usually with a higher end scan tool that can communicate with the 4WD module
since it does 2 hi to 4 hi no problem we know the 4WD module is good and the powers and grounds are good as it would not shift into 2HI and back to 4HI if that was the case
this narrows this issue down to an internal transfer case issue or the encoder motor on the transfer case causing this problem most of the time
the best action to take is to remove the motor off the transfer case and see if you can shift 4LO by hand using a wrench or vice grips on the shaft the motor came off of
if you can NOT shift 4 LO by hand then there is an internal transfer case issue
if you can shift 4LO by hand then the odds are replacing the encoder shift motor on the transfer case will correct this issue
usually the shift fork for 4 Lo is the most common issue
alot of times picking up a used complete transfer case from a junk/salvage yard is the cheapest way out then just swap it out into your truck
they come with good warrentys with them and just change the fluid and replace the rear output drive shaft seal and it should be fine
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