Chosen Solution

Hey there, I bought a 98 gmc 1500 5.7L and the 4x4 does not work I was wondering how I go about troubleshooting the issue to find out what the problem is? I was told by the seller its the transfer case but i was talking to my friend about it and he doesn’t think that’s the case because it isn’t grinding when I put it into 4h or 4L. There is a manual shift gear inside, not lock hubs. Please help as I am a self taught mechanic that doesn’t know a lot but willing to learn! Thanks in advance.

When you select 4H or 4L what actually happens? If going up an incline dirt is best, does a person outside the vehicle see any wheel slippage? Do you feel wheel slippage? Sometimes the high and low are selected by solenoids aka electrical and not mechanical. A fix most Mitsubishi owners will know about is, putting the vehicle in 4L and reversing backwards about 10 meters. Then putting driving forward. Sometimes this unsticks the solenoids or whatever is locking it up. Another test is to look under the vehicle from a distance and see if the front drive shaft is engaging when moving forward. Not something you will see if it is a solid diff. Or simply put it in 4H and do a burnout and see what wheels spin and what doesn’t.