1 wheel drive. whats wrong?

It could be just a blown fuse, or a wire disconnected/broken or a corroded connector somewhere, or even water got inside the controller somehow.

I've never seen one with push button control.

On the older model, you engage 4wd with a mechanical lever, then a switch in the transfer box activates the controller that operates a vacuum valve to engage the hubs. If the vacuum is tight, the 4wd light comes on.


I suspect that the switch activates a servo in the transfer case to engage 4wd, and operates the valves for the hubs when the switch on the transfer case confirms it is in 4wd. If the switch isn't working the light won't come on or the hubs engage.

Someone did report that he snapped the wire off the transfer box switch bashing it on a rock once.

If it is under warranty, get the dealer to look at it. (Don't mention the handbrake thing)

You mentioned that you can hear the hubs locking - can you hear the hubs or a hub locking?

Get someone to put it in and out of 4wd whilst you run around listening to each hub. If one doesn't lock you'll only have rear wheel drive and as has been said before, the wheel with the least grip will spin - which is not unusual at the moment and on the slippery surface you are on!

Hopefully it's just crappy vacuum hubs not working properly for you.

Kirkynut

As you have an electronic transfer box perhaps the noise you are hearing is that engaging and not the hubs. The hubs can also click and not duly engage.

Martin

I went to the car and its not the 4wd fuse. Had another look underneath and there is a sign of oil which i think is comeing from the transfer box. Its hard to do anything as there is a foot of snow on ground. Hopefully the snow will hold off so i can get it somewhere i can work on it.
I can hear the hubs locking, well what i think is the hubs. Will the rear wheels make a locking sound or is it just the front wheels? Also does the rear dill lock when 4wd is engaged? Or how does it actually work?
Thanks

When you move the transfer box lever from 2WD to 4WD.....

1. The vacuum hubs lock on the front wheels (you may hear a click from near the front wheels)

2. When the system THINKS the hubs have locked (they may not have) then a soleniod moves the transfer box into 4WD, you may hear a clunk from the transmission tunnel area.

Today i finally got to spend a bit of time on it. I put the car in 4wd and took hubs off. Both are locking. The prop shaft is spinning to the front diff when in 4wd but not in 2wd. So transfer box is working ok. Why it was in 4wd i was turning the drive shaft by hand when hub was off. Is that normal? That was for both sides.

If the hubs are locking, and the front prop turning with the transfer box, but the wheels don't, then one of the CV joints has failed, usually from using 4wd on tarmac roads.

Select 4wd in neutral, leave handbrake on, jack up only one front wheel, and try turning it around by hand. It should only move a short distance each way with a nice healthy clunk from the differential. If it rotates, and the hubs are definitely locked, CV joint failed.


If you try this with both front wheels off the floor, they should rotate in opposite directions, due to the gears in the differential.

So if one cv has broken then that will stop both wheels from turning in 4wd?

Yes.

The gears in the differential transfer all the drive to the wheel with least resistance, so if one was on ice it spins when the other is on tarmac. A broken CV joint means no resistance at all on that side, and the broken shaft spins inside the joint. Might make a noise, might not.

The same thing happens if one hub isn't locking, the drive shaft inside the hub just spins easier than the other side that has to turn the wheel as well.

Ok thanks.
So i need to strip down the front to see which side has the broken cv. Is there an easy way of doing that?

Today i had time to look at the car. First i jacked up the front passenger side with hubs locked. Wheel was spinning freeley. Then same on other side. So from what you guys said i thought id look at cv joints. i strpied down passenger side and its fine. After refitting everything i had the car in 2wd and got under car. I was turning front prop by hand and its now getting so far then just stops dead. If you give it a little wiggle back and forth it slips and moves on. When i put it in 4wd and try drive it moves forward a foot then locks up. Same in reverse. It there something obvious going on here or do i strip other side down?
Also when i was sliding drive shaft back in i had trouble gettong it back in. I had to lift the shaft up a little. I wouldnt just slide in. Is that normal?
Thanks for any help.
Gav

Something is up so you have to start the process of elimination and I think it could be the other cv so I'd pull that apart. Did the cv move smoothly in all planes on the side you checked.

It can take a while of jiggling to get the shaft in the diff. Try putting a finger under the axle seal to support the shafts weight and act as a pivot point.

Kirkynut