4wd Issue, lights Work, Drive shaft spins

[TACORUNNER]

I've got a 2001 4runner Sport which has the Electronic Differential Actuator. When I put the runner in 4wd
, the 4wd lights work properly and the front drive shaft spins but the truck won't move. Is it possible the actuator needs replacing or does it sound like something else?

When I lock the center diff, only the rear wheels turn.

 

[02SE]

Explain exactly what you do to put it into "4wd".

 

[TACORUNNER]

I've tried both 4H and 4L and get the same result. I've got the push button shift on the fly and have attempted that while in Neutral stopped, neutral rolling, drive rolling slow etc..

I've also attempted 4low via the shifter while in Neutral.

The 4wd indicator shows the steady green lights as it should and turn offs when in 2wd.

 

[ajonesnv]

Sounds like it is not locking at the t-case, though when you use the shifter it should manually lock the t-case.

If the ADD were and issue, Im sure the 4wd light would blink at you...though it should also blink at you if the electronic actuator was not working.

One of two issues is happening. The ADD is not working, I which case Id look for vacuum leaks to start and check the connections at the diff. Or the Actuator at the Diff is not functioning.

Either way if one is not working and the other is, your drive shaft will spin without being in 4wd.

One way to narrow the problem (a very dangerous if not done carefully) is to put the truck on jack stand and run the system. If you engage everything and the front drive shaft is spinning you have an ADD issue, if not you might only have a t-case actuator issue.

 

[TACORUNNER]

I've got another 4runner I can pull the front diff actuator off of and swap them out. I'm pretty sure I'll have to drain the diff to complete and drop the diff down to remove the actuator. anyone know for sure if the diff needs to be dropped to remove the Actuator?

I'll keep u all posted as this is the first time I've heard of the 4wd lamp functioning correctly but the 4wd not working.

Thx for the reply.

 

[habanero]

Dif is upside down, actuator is on passenger side, towards the rear

In truck. Actuator is dirty and hard to see behind the tube but it's there. The yellow ring is the nut you have to undo to lift the dif up out of the crossmember. Well, that, the cvs out and the front diff mounts and detach vacuum lines and electric from sensor by the actuator...

The actuator sits just under and a little to the passenger side (right) of the tranny, just above the cross member... tight even with a 1" bl. I've not tried it in truck so no help to you there. That particular vacuum line can be reached easily in comparison. It runs to a trio of metal lines on the top of the dif and from the metal lines back to vacuum hoses and up the left inner fender.

 

[TACORUNNER]

Dif is upside down, actuator is on passenger side, towards the rear

In truck. Actuator is dirty and hard to see behind the tube but it's there. The yellow ring is the nut you have to undo to lift the dif up out of the crossmember. Well, that, the cvs out and the front diff mounts and detach vacuum lines and electric from sensor by the actuator...

The actuator sits just under and a little to the passenger side (right) of the tranny, just above the cross member... tight even with a 1" bl. I've not tried it in truck so no help to you there. That particular vacuum line can be reached easily in comparison. It runs to a trio of metal lines on the top of the dif and from the metal lines back to vacuum hoses and up the left inner fender.

Thx for the pics and info. It's going to be PITA to get the actuator off.

 

[TACORUNNER]

The front diff Actuator was the Culprit. I'm back in business. Thanks!

 

[kyrin]

I think I'm having this exact problem with my 4runner. How much work was it to replace the front diff actuator?