1996Taco

Hey guys,

I found similar scenarios to my problem on here, but I am still not exactly sure what to do first. We just got our first real dusting of snow this year and it was the first real time my tacoma sort of let me down.. When I went out tonight to test out how my Kumho MT's would do on the icy/snowy roads I found out my 4wd was not working. Usually I put the shifter into 4wd (NON button shifter) and I hear a 'click' sound in the dash area. Once I drive a little I then usually feel/hear it engage and the green 4wd light comes on. Tonight it would not do any of this..

There was no 'click' sound from the dash area and I couldn't feel any engagement. The only thing I noticed was that in 4 low the rear end was definitely in low range. However, the front end would still not engage and no light was on the dash. From what I could tell in the dark with the flashlight was that the vacuum hoses are all connected to the actuator. Its been in the teens and the twenties here lately, but its worked in much colder weather before. I think I even tested it a few weeks ago and it was fine. I just moved out here (Oregon to Indiana) and no longer have access to a mohawk lift or tons of tools.. Just my luck. My truck is a 1996 Tacoma 3.4L V6 manual tranny with 225,000 miles on him. I have the ADD.

Any idea on where I should start first? I am hoping a friend will let me use their garage soon because I dont want to work on him outside haha Maybe a sensor is dirty or bad? If so, which ones could they be? The ADD relay?

Thanks for the help!

1996Taco

So it has warmed up to about 23 degrees this morning and somehow the snow is thawing? ha The front end would still not go into 4 hi/4low even after I warmed him up and drove around. However, in 2wd the short drive shaft to the front end spends freely. When I placed it in 4 hi and 4 low it would not. So I know my transfer case is working fine. The front differential is just not engaging into 4 hi/low.

I decided to sit in a parking lot in 4 low for about a minute trying to decide what to do next. I had the right side kick panel off because I believe the ADD relay is there (I see a transmission relay, but no ADD relay? Same thing?)? Anyways, after a minute sitting there something starts clicking like crazy from the right kick panel. It sounded like morse code haha It definitely sounded like the relay when you put the truck into 4 low/high, but instead of clicking just once, it was clicking non-stop. Loud normal clicks and quieter clicks. Longer clicks and shorter clicks. The 'clicks' sounded like putting a wet frying pan on a hot stove top (I first thought it was short circuiting. Maybe it was ha). I started to barely move and he went into 4 low. I drove around for about 15 minutes going from 2 hi to 4 hi to 4 low and back. No hiccups after that. I could also feel/see the front end pulling now.

So why did the front end randomly decide to go into 4wd? Why such a long delay sitting there for literally a minute before the relay started to 'click'? Was something frozen on the front diff (although it was completely warmed up long before it started to work)? I'm worried my 4wd will let me down again on another cold day. I'm taking my truck to Minnesota for Christmas. Thats about 550 miles one way in some cold cold cold weather. The highs of where I am heading to have been in the negatives lately...

Any thoughts on my issue are greatly appreciated! Thanks!