3rd gen 4wd won't engage but light is on

Went to put the '99 into 4wd the other day and the light came on but it was only in front wheel drive. Anybody else experience this? Looked through the manual and don't see much about it in there.

 

Is it a J-shifter or a ? I'm going to assume it's the J-shifter because it was more common on pre-2001 4runners. I'm assuming you meant to say rear wheel drive only, front wheel drive only should be impossible since these are normally RWD.

I've experienced shifting it into 4wd and having neither the 4wd light or 4wd come on, the problem resolved itself mysteriously and exercising it monthly solved it ever since (2 years since). The chain driven transfer case is dead reliable, if you can't turn the front driveshaft by hand in 4wd it's not your problem.

Having issues with 4wd is a common issue, it's usually in the front of the car, either the ADD (automatic diff disconnect) or the vacuum system that works it. Also some actuators that go bad too. , I know yours have the light on but the items that they say to check should be checked since they are so common.

 

Appreciate it. I did mean front wheel drive. That’s part of why I’m stumped on it. I found this out because a buddy and I were in the pass in snow and we ended up having to pull the 4Runner out and noticed the front wheel drive problem when revving.

 

So your rear wheels aren't getting power so going into 4wd makes the 4runner transform from rear wheel drive to front wheel drive. That's wild.

I don't know how that's possible because 4runners have 4wd, meaning power is hard split 50/50 front rear. So if your rear wheels aren't getting power your TC is broken or you have a VF3AM transfer case with its center differential unlocked.

Does your rear driveshaft spin freely, do your rear wheels get power when you go back to 2wd? Does 4 low work at all, or is it just 4 high issue?

What version of 4wd do you have, the VF2A transfer case or the VF3AM one?