4WD problems

I have a '90 Carry with a 5 speed tran. no hi/lo. The 4WD has been working ok, then intermittent problems started. Sometimes it will go into 4WD and sometimes not. When it won't go the axle-lock light does not come on. Sometimes after a few minutes it will come on, then everything works. I can hear the control unit under the dash click when I shift the lever into 4WD. I discovered that the truck does not have to be running for the axle-lock light to come on when it is working correctly. When the axle-lock light comes on it will go into 4WD but if the light does not come on, no 4WD. It does not appear to be a vacuum problem since the axle-lock light will work with just the ignition switch on. Any suggestions?

Also if it is an electrical problem, can the solenoids at the differential be by-passed and a vacuum run straight to the diaphragm actuator to keep the truck in "full time" 4WD?

Thanks for any help.

 

Thanks for all the help. I see this this is just another typical "clicque" forum.

 

no need to get upset,some questions take a while to get answered unless you update them.
I too have a 90 5spd and have had problems with the diff,buthave had no probs with the axle lockfunction.
Are you in a cold climate??
do you have a crap buildup on top of the front diff? I have been told that this can cause the diaphram ontop of diff to not fully operate.
Have you searched old posts to see if there are other posts with the same question/different model ?

 

runningw...If someone knew the answer to your question they sure would help you out. In time someone will figure it out for you..Don't get frustrated.

 

My truck has to be running for the axle lock light to come onooops, sorry my light will come on without the truck running,but with the truck running you have to hold the button down for 5sec to get the light on.

 

It could be that the front hubs need servicing [?] lube [?]

As Tinytoy asked how cold is it where you are at ?

How many kms on truck ?

Try jacking up the front end - both wheels off ground then turn on truck in NEUTRAL, push "Axel Lock" button,
then turn each wheel by hand [rock back and forth] it shoud be already engaged
to axel but if it isn't then the rocking motion should engage it if it is hanging up.
You should be able to see the axle turn and also you can double check that the vacuum diaphram is pushing/ pulling as case may be.

Regardless of everthing else working [vacuum, electrical, etc] if there is something hanging up internally in hub then it's not going to engage.

Just some educated guesses on my part.

 

Thanks to all for the help. I got a service manual and started tracing the wiring and checking for voltage. It turns out that the 4WD controller behind the dash isn't sending power to the solenoids at the front diff. or the light on the dash. A separate hot wire with a toggle switch took care of the problem until I can get a new 4WD controller box.

 

You probably know this already but I didn't until I had mine for over a year...the 5 speeds with no '4 low' have an extra gear when in 4x4. I found mine strictly by accident one day since I had no manual and it isn't on the gear shift knob. When in 4wd you can go one detent to the left of 'normal' 1st gear and there is a REALLY low gear.

Just FYI in case you didn't know.

 

bad linkage

I thought my 4 wheel drive system was either having electrical or vacuum problems.

Turns out the linkage was undone for some reason, right by the diaphram.


has anybody ever seen this before?

 

runningw, I'm having a similar problem. Where is the 4wd controller located and what does it look like? I've had the truck for over a year and a half and never had a problem using 4wd but of course on the first snow fall this year...sometimes it works, sometimes I curse it!

 

I finally got to try the 4WD tonight in the snow, works pretty good. Mind, it was only a couple of cm's of the stuff. Should find out more tomorrow when it turns into ice!

 

Jason, (out here in Maple Ridge) I agree with you, they work great in the snow, I just never know when it's going to work the last couple of days. I was going through Surrey this morning and the roads were like the Olympic speed skating oval and I couldn't get 4wd to to work. As light as they are, when the roads are slippery and you're in 2wd, they don't get around too good!

 

Marshall I started off in 2WD until I came up on the first accident. I can't figure out how 2 cars going side by side on a straight, level 4 lane road can collide so bad and spread bits out over 4 lanes .... I mean, there's no hills out here in Richmond and #5 Road is 4 lanes from one end of the Island to the other .... I turned on the 4WD after that though and it was great. I think that the getting going isn't so bad, it's the stopping with these little guys. Good thing I've got oversized tires on! The extra 3cm per corner really helps! I can't wait to try the 4WD out on the ice tomorrow !

 

air marshall,the controller box on my truck is behind the glove box. The glove box can be removed, then you can see the control box to the upper left behind the glove box. It is black, about 3"x5" and has a bunch of wires attached to it.

 

I added 2 twenty Kilo bags of sand right up against the tailgate ( inside a truck inner tube so they don't feeze and bang around ) It really hepled the ride and traction.