ksig4runner

Last time i went out, my front differential would not engage and i have no front wheel drive at all. The 4wd selector shifts fine but i have no light go on and nothing seems to be engaging.Is this a problem that anyone has had??

VolcomTacoma

I'm guessing you have the ADD system, not manual locking hubs right? My 93 which had ADD, also had the 4wd light problem. It would flicker after using 4wd for a while or just not turn on at all, which caused the front diff not to engage. I ended up converting to manual hubs and defeating the ADD system(writeup here: http://www.4x4wire.com/toyota/tech/add/). The light would still act up, but at least my 4wd would work reliably now. I never found out what the problem was and still did it after all the vacuum components were removed, but guessing it was the switch in the front diff.

mastacox

My guess is you have a leak in the vacuum line that leads to your ADD system... It's pretty common even though I have never actually had this problem... You could try looking at the lines and see if they are in one piece.

http://www.off-road.com/toyota/tech/add/index.htm should help with checking the system out.

The little green 4WD light not turning on means the ADD is not engaging, most likely a vacuum malfunction.

rpeAMP

Also try driving for several minutes in 4Hi. When I first bought my 4Runner, the 4WD virtually hadn't ever been used, so it took about 5 miles to get it the light to stop flickering and for it to engage firmly.

tombothetominator

i 2nd the vaccum check!