$WD Not Engaging on '04 Taco

bajajoaquin

Adventurer
My brother has an '04 Taco that doesn't seem to get power to the front wheels (yes, it's a 4WD model ;) ). He put up a post on TacoWorld forum or some such, and didn't get any response.

His post:

I have the push button 4wd system on an 04' TRD V6 doublecab with the automatic transmission. When the button is pushed, I still hear the click of the switch, but the indicator light doesn't come on and the front wheels aren't powered. However, I can shift the lever into 4wd low and the rear diff lock will engage. My truck has 120,000 on it and a sizeable portion of that with 4wd engaged in the snow and in baja. I first noticed the problem last Christmas in baja but was able to get the system engaged by turning the system on and off while accelerating, braking and reversing. When it does turn on/engage, there's is no difference in the sound of the system as the button is pushed. Later in Mammoth, I tried the same routines, but it only came on after driving 5 or so miles. Any ideas? I tried a search but didn't see a thread with my equipment or specific problems. thanks for the help!

Some additional detail from a conversation we had: When you shift into 4-Low, the gear ratios indicate that it's in low range, and the electronic locker will engage (it only does so in 4-Low), but there's still no power to the front wheels.

That makes me suspect the front hubs, rather than the transfer case.

Anyone have any ideas?
 

Martinjmpr

Wiffleball Batter
That makes me suspect the front hubs, rather than the transfer case.

Anyone have any ideas?

There are no "hubs" on that generation of Toyota, what it has instead is the ADD or Automatic Disconnecting Differential. The ADD is a vacuum operated system and it does sometimes go bad (this is true whether the 4wd switch is the pushbutton type or the manual J-lever.)

I think Yotatech has some good troubleshooting tips for both the pushbutton T-case shifter and the ADD.
 

Forum statistics

Threads
185,538
Messages
2,875,655
Members
224,922
Latest member
Randy Towles
Top