4Runner Pulling Left Under Acceleration

[Tucson T4R]

OK, I'm stumped. I just noticed this on my 2004 4Runner. Never noticed it before and I just got the 50K service done last weekend with no problems found. Only under acceleration it pulls to left, hard enough you have to counter steer against it. The more you accelerate from a standing start, the more it pulls.

As soon as you stop accelerating and just roll, it tracks perfectly straight. It also tracks straight when braking either softly or full on hard stop.

Even at speed, if I am just rolling along at 50 I am tracking straight as an arrow. When I accelerate it starts to pull to the left again until I get off the gas.

I checked the air pressure and all 4 tires are at 37 lbs. Anyone have an idea of what might cause this symptom?

 

[heeltoe989]

OK, I'm stumped. I just noticed this on my 2004 4Runner. Never noticed it before and I just got the 50K service done last weekend with no problems found. Only under acceleration it pulls to left, hard enough you have to counter steer against it. The more you accelerate from a standing start, the more it pulls.

As soon as you stop accelerating and just roll, it tracks perfectly straight. It also tracks straight when braking either softly or full on hard stop.

Even at speed, if I am just rolling along at 50 I am tracking straight as an arrow. When I accelerate it starts to pull to the left again until I get off the gas.

I checked the air pressure and all 4 tires are at 37 lbs. Anyone have an idea of what might cause this symptom?

Hmmm, It definitely sounds like torque steer, but thats more common with front wheel drive, not rear wheel drive. I wonder if a motor mount or tranny mount is starting to go and starting to twist the drive train. It also might be a rear tire, a belt may have moved or is shifting under load and is creating the truck to turn under acceleration. I'm not sure what else it could be. Try swapping the tires around and see if that cures it. If it does its a tire problem if not its something else.

 

[taco chaser]

I don't know to much about the new 4 runners but if there still coil sprung rears like the old ones, it could be that your rear track bar is lose or needs to be adjusted. Question do you feel the pull in the steering wheel like it's coming from up front or doe's it feel like the rear is pushing side to side?

 

[heeltoe989]

I don't know to much about the new 4 runners but if there still coil sprung rears like the old ones, it could be that your rear track bar is lose or needs to be adjusted. Question do you feel the pull in the steering wheel like it's coming from up front or doe's it feel like the rear is pushing side to side?

X2 on that.

I forget that the runners are coil sprung.

 

[Tucson T4R]

Good ideas folks. Thanks. It's coil front and rear on the 2004. I'll go check that the rear coils are seated properly. I did some serious wheel standing four wheeling a couple weeks ago through some rough country so something could have been shifted out of position.

I'll go take a look underneath and let ya know. Thanks.

It's also constant four wheel drive so tell me more about "torque steering". That is what it feels like. Feels more front driven than rear push.

 

[heeltoe989]

Good ideas folks. Thanks. It's coil front and rear on the 2004. I'll go check that the rear coils are seated properly. I did some serious wheel standing four wheeling a couple weeks ago through some rough country so something could have been shifted out of position.

I'll go take a look underneath and let ya know. Thanks.

It's also constant four wheel drive so tell me more about "torque steering". That is what it feels like. Feels more front driven than rear push.

Torque steering usually apply to front wheel drive when the drive shafts are different lengths and creates a pull to one side or the other.

I think something has shifted in the rear too much and loosened up, now when you put the power on the body and suspension its flexing something and moving out of place and causing and aliment issue in the rear which pulls you off coarse.

i would have a good look at everything in the rear and front and check ever bolt that deals with suspension to see if one is loose. If everything is good at the rear, check the front.

 

[Tucson T4R]

Thanks for the input. I checked the rear coils and they are seated properly top and bottom and all the rear links are solid.

I also heard that a broken front dif mount could cause this. I dropped the front skid pan and checked the front dif mounts. They all look solid with no evidence of cracks or damage.

 

[taco chaser]

I really don't think it is drivetrain related, but do you have lockers?

 

[Tucson T4R]

Nope no lockers on this one. The tires were rotated last weekend with the 50K service. Maybe I should have them rotated back and check the alignment.

Sounds goofy to me though. Every tire or aligment problem I have seen in the past was pretty constant and not just under acceleration.

I appreciate all the thoughts and input.

 

[heeltoe989]

Thanks for the input. I checked the rear coils and they are seated properly top and bottom and all the rear links are solid.

I also heard that a broken front dif mount could cause this. I dropped the front skid pan and checked the front dif mounts. They all look solid with no evidence of cracks or damage.

The only thing I could suggest is to do a tire swap. front to back and back to front to see if it changes anything. Maybe one of your tires have shifted and belt has come unglued and is moving around when you accelerate. I had this happen on a set of BF AT, one gave me terrible vibrations at certain speeds and pulling in corners.

 

[Tucson T4R]

I'm running BFG ATs so I'll check it out. Thanks.

 

[4RunAmok]

Those are rear disc brakes, right? My rear drums caused something like this. Punk kid who adjusted them at Toyota when they did my rear seals over-tightened one side. Hard pulling, and horrible gas mileage.

 

[Tucson T4R]

Four wheel disc brakes on this one. All four running cool and work great when stopping.

 

[Redline]

I'm also thinking some kind of 'tire pull', though its under acceleration, and usually tire pull is constant. Easy to rotate the tires and at least eliminate it as the problem.

The only thing I could suggest is to do a tire swap. front to back and back to front to see if it changes anything. Maybe one of your tires have shifted and belt has come unglued and is moving around when you accelerate. I had this happen on a set of BF AT, one gave me terrible vibrations at certain speeds and pulling in corners.

 

[Tucson T4R]

Yep, after checking all the obvious possibilities, I'll try the tire roatation tomorrow and see how it reacts.

Look at the bright side..my front dif mounts aren't broken from my wheeling a couple weeks ago. :26_7_2:

I'll let ya know what I find.