4WD drive feels tight - '98 Jimmy

sbar1564

just bought a 1998 jimmy with 3 button switch when I put it into 4hi it locks in and works with a whine but feels like it is being held back. You have to give it some gas pedal to move it and if on a hill and in neutral it will not roll take it out of 4hi to 2wd it is fine. Thought maybe the ABS was doing it so removed the fuse no change. I took all 4 wheels off ground in 2wd and neutral it is fine brakes work fine and release fine. In 4hi right rear wheel is tight would not move by hand. In drive the 3 other wheels move fine but right rear moves a lot less and seems to struggle. Tied off the brake caliper so it wouldn't be a factor but did not help. Does the right rear not drive in 2wd?

thecardoc3

Some of these system do not have a differential in the transfer case, so if there are different sized tires ( tire wear included) the car won't move easily because while the wheels and tires would have to turn at different speeds the drivetrain tries to force them to turn at the same speed. The result is a wheel has to slip for the car to move. When driven on snow or ice it isn't a big deal but on dry pavement you get the symptom you described.

sbar1564

all the tires are a matched set

zandor60657

I did a little digging online, and while I'm not sure this is correct it looks like there were two 4WD systems offered in the 1998 Jimmy. One is part time, the other full time. The part time version has 3 buttons while the full-time version has a locking center diff and 4 buttons. Presumably the additional mode in the full time 4WD version is 4hi with the center diff unlocked so you can drive it on a paved road. Part-time is good old fashioned off-road or snow only 4WD.

sbar1564

yes I have the 3 button system (2wd -4wdhi -4wdlo)