Namu Mac

Went to put my 91 XJ into FWD to day and nothing happened. Wha are the common problems? Vac. lines unhookled? Any info appreciated.

tampaviking

If the shifter moved real easily then it could be disconnected from the T case.

Metmknice

Not to be much of a smart alec.. but it would be 4WD. FWD = Fail Wheel Drive aka Front Wheel Drive (=

LCFRJEEP

Do you have the vaccum disconnect front axel?? If so, I would check there. Good Luck!!

muddeprived

Air leak in the vacuum line is probably your issue. It's common on the vacuum disconnect front axles. You can fix it, or convert it to a solid one piece axle, or get a junk yard non-disco dana 30 and replace it with that.

wicked_xj

or u need to ghetto fy the body shift rail bushing and put a cotter pin/trailer hitch pin in its place

offroadohio

check to make sure the vac lines havent come unhooked at the axle, and at the frame rail just past the control arm. I had to replace my stock line swith logner ones becuase I kept pulling them apart.

caged

quick and cheep fix is to remove the actuator from the front axle, slide the collar across the shafts and install a gear clamp against the collar and tighten it to hold the collar in place.
re-install the actuator and enjoy fwd.

wicked_xj

x2

Namu Mac

Problem solved. The vacuum connector at the actuator was a loose sloppy fit. I think that over time & so many oil changes the connector was soaked in so much oil it was not fitting tight on the vac. nipples. The oil from the filter drains directly on the fitting. I used some small zip ties and clamped the connector down and clunk it goes into 4wd. easy & cheap fix for now.

Schmidtjw

My vacuum system is shot on my dana 30 and on my transmission. I was considering locking my 4x4 in all the time. I drive my jeep on the road more than off road. are there any negatives to keeping the axel locked in all the time. Will it affect my fuel mileage or drive ability of my jeep at higher speeds or turning on pavement. Also is there any negative for my transfer case its a NP231, which was not built for all time 4x4.

hubbazoot

Yes, extra wear & tear on your whole front end, tires, differentials, etc. Shudders and shakes around turns, reduced economy, reduced turning radius. 4wd high also has a maximum recommended speed of 55mph.

I would not recommend this option at all.

Schmidtjw

Will it have those negatives if I leave the transfer case in 2 wheel drive. im only wanting to lock in my axel. Sorry my truck has locking hubs so I don't really understand why they would lock the 4 wheel drive in where the u joints keep spinning

hubbazoot

You'll still be putting extra strain on the axle and wear on the tires. You'll also still get the shudder going around turns.

muddeprived

i would convert your discnnect axle to a non disco axle. you can swap in a newer dana 30 or throw in a one piece shaft in place of your two piece. you have to repolace or add some seals or something but its not a big project. this will allow you to get 4x4 when you need and not have to deal with the problematic disco axle.

you cant run the np231 in 4x4 on the road, unless its snowing or very wet to alow tire slippage and prevent binding.