Hey, I recently bought a 1991 comanche, 4.0 ,5 spd, 4WD, and the 4WD always worked perfectly. I went to use it the other night and nothing. The light would come on but go off as soon as i started going. I tried low range and the truck was in low range, but no 4WD. To me this means the transfer case is fine, but for some reason the front wheels arn't engaging. Where do the vacume lines connect, i looked but couldn't really find them (im new to comanche's). Is there any other parts in the front end i should check? thanks
as far as I know, the problem your having is with the vacuum actuator thingy on the back of the ps axle tube.
I had the same problem, and I fixed it using a throttle cable from a truck, and about 80 cents worth of fittings, and a spring. It was fairly simple to do also. So if you have the money to get a replacement then go for it, but if not (like me) go ahead and do the manual fix.
It could be the vacuum switch on the tcase, a leaking/broken vacuum line, or the axle shift diaphragm has given up the ghost.
The posi-lok would cure it no matter what. But so would a solid axle from a non-disconnect XJ/MJ/ZJ/YJ D30. You can also remove the shifter from the axle and manually place it in the engaged position, re-install it and cap off the vacuum system and just leave it engaged.
Not on any of my personal vehicles, I have ridden with many a YJ owner that swear by them. I found them cheapest at Collins brothers in Texas. http://www.collinsbrosjeep.com/main.htm
You can do a search on the YJ forum for their opinions and recommendations.
WOW
am i glad i looked here
the 4WD on the 88 commanche isn't workinig, and if i finagle the cables it will work
meaning i pull the lines off the axel.
and then the dam light always stays on in the dash too
it's an 88 auto MJ
i looked for manual hubs could never find them, so now after reading this thread i can see what we can do to make it work
the only Q i have is i'm wondering if there is something with the vacuum lines, there is a blue colored vacuum line hangin in the passanger side engine compartment that i capped off, the line is the same style as the ones that go to that diff vacuum swich, was wondering if something was messed up
i think i have photos of it if anyone wants to see
but since i like manual control, i will look at this posi thingie.
WOW
am i glad i looked here
the 4WD on the 88 commanche isn't workinig, and if i finagle the cables it will work
meaning i pull the lines off the axel.
and then the dam light always stays on in the dash too
it's an 88 auto MJ
i looked for manual hubs could never find them, so now after reading this thread i can see what we can do to make it work
the only Q i have is i'm wondering if there is something with the vacuum lines, there is a blue colored vacuum line hangin in the passanger side engine compartment that i capped off, the line is the same style as the ones that go to that diff vacuum swich, was wondering if something was messed up
i think i have photos of it if anyone wants to see
but since i like manual control, i will look at this posi thingie.
What's a commanche? You must have a rare one if it's really a commanche. LMAO :laugh: :rofl:
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