Why does my bro's 4wd work so smoothly?
made me realize mine isn't

Sometimes mine grabs a little when shifting into it. The part time light never works now. But it used to come on and go off with a jerking in the front end. I thought in my playing I had broken the axle but while rebuilding it for seal leaks I ruled that out. So I now think I have a vacuum leak or a bad vacuum motor. It has 2 lines on it I assume one is a vent and one is a vacuum. Is there an easy test to this? As if this is a problem it seems it was dropping vacuum while in the hills.

Also his Lowrange is WAY lower then mine. It has a manual and mine is an auto. Same engine but his is a sport and mine is a laredo. 1990late vs a 1992early.

I have heard of a filter or check valve under the hood for this vacuum. I am going to check it tomorrow. Which sensor turns the light on? I assumed it was the one mounted to the vacuum pump.

 

It is most likly the vac motor or bad line,I've never tested them cause I have a 92 also which does'nt have a vacum operated 4wd.My buddies went bad and he just elimenated it with a cable system from quadratec.I think it was about 200.00 buck's,