This whole problem is very confusing (understatement). Wouldn't ATRAC be involved at some point in this scenario? It seems with the AWD system that regardless of what happens to the front diff there should still be some power going to the rear.(?)

This has to be an electronic problem of some type. Remember the post about the guy who had replaced his horn with aftermarket and some time later out of the blue after filling up with gas his 4R died 60 ft. later and that was it until they discovered something about that horn and it overloading something that led to a failure of a power module or something?

This sounds weird like that one.

I am not 100% sure how ATRAC works. If ATRAC is dependent on the ABS sensor and a wheel spinning, to determine if it needs to redirect power, then I don't think it would do anything because none of the wheels are turning whatsoever. The only thing turning is the front driveshaft. And to add, when I put it into Park, my 4Runner will freely roll; I would think ATRAC is out of the picture at that point.

My mechanic now thinks it's some control module around the steering column causing the issue?!?! I have no idea now. I tried to tell him I thought it was the front diff and he seems to think otherwise.

Yes, as I understand it there needs to be a wheel w/o traction for ATRAC to get involved. I have an '07 Highlander, AWD, had it on jack stands with all wheels off and started it up, put in drive and the ABS had the all the brakes applying constantly, sounded like a calypso dancer and it almost jumped off the jack stands! Was very interesting. I thought this is what you did. You might try it just to see what happens?
Have not tried it with my 4runner, afraid it might just jump off the stands since it larger than Highlander.

How does a steering column control module (which I've never even heard of) cause a loss of power to the wheels? This is your transportation, critical, time-consuming stuff. Try to get these part names nailed down. Pull out your phone, ask him to tell you whats broken again, and type it into notepad or something so you can look it up later and make sure you're not being fed a line of BS, which it sounds you are.

It also sounds like you need a new mechanic, even assuming no BS. How many trips in is this? Auto repair 101 - don't throw parts unless you know what's wrong. You don't replace a solenoid unless it doesn't move when 12v are applied to it, etc.

If your front driveshaft is turning and the front wheels aren't there is a malfunction in either the differential or both CVs (which seems highly unlikely). Where is the video? Upload it to Youtube and link here.

Drain the diff oil and check for metal, as was said already. Do this yourself. You're being taken for a ride by "your" mechanic.

You say the front drive shaft was turning but no front axle? Was that by the power of the motor or were you turning the drive shaft by hand?

Sounds like front diff issue to me. I think the V6 has an actuator to activate the front diff and assumed the full time 4 of the V8 does not have it because it’s never off but I could be wrong


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Yeah, I am getting it back. This guy has worked on a few cars/truck for our family before without issue. I am not sure what is going on with him with my 4Runner.

I have been hesitant on working on it myself because 1.) I have not worked on major drivetrain components before and lack any experience troubleshooting it (except for replacing the CVs). 2.) I have 2 other "projects" in the garage that are not drive-able.

To add, my driveway is sloped.

Anyways, here the link to the video: Bad Front Diff Video



If you look to the right, you can see the front drive shaft spinning when I put it into gear.

If you put it in park and it still rolls freely then that says its not in park for some reason. Mine doesn't roll in park, no vehicle should roll in park unless there is something definitely wrong, the trans not getting the message you are in park.
There have been vehicle recalls because vehicles rolled in park.

If this is so, there must be something wrong in the trans.

I'm really anxious to hear what you find wrong!

I've rolled in park before. Unlocked t-case does weird things under the right circumstances with driveshafts or potentially CV's disconnected.

Yeah, with rear driveshaft disconnected I can see that, it would almost have to roll unless park brake on.

A stripped out front diff has the potential to be basically identical to a driveshaft being removed. Comes down to how the center diff behaves if in park and no contact between front or rear wheels, and center diff. In low torque drive situations it behaves like an open diff, but what does it do in park? I don't know enough about the torsen function to say one way or the other, but DS spinning and wheels not turning is a huge red flag for front diff.

I’m just going to throw this out there: have you considered getting an opinion from a Toyota dealership?

Old one is out. One CV would not pop out though.

Replacement one is partially in; I am having a hard time getting the breather tube bracket bolted back on. Any one with suggestions on that?

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Going it for it eh? Congrats, looking good! Looks like both CVs are out, just the intermediate shaft? (nm I see boot now, couldn't zoom on phone) If no one who's replaced one of these comes along, might describe what issue you're having with breather tube, and pic would help. Just can't get to a bolt?

Were there metal shavings in the oil?

Looks like good work. How many miles on this 4WD 2003? I have 150,000 miles on SR5 2005 2wD. Owned since new.

Never had a Code triggered in 15 years. Few problems. These 4 runners are tough.

Never seen the part in your 2003. Is it in front wheels?

Bad wheel bearing a few years ago. Tranny and engine have been fine.