Mini Van Pulls to the Right

[Brother]

My 2003 Toyota Sienna XLE pulls to the right. To drive down a level road, I have to hold the steering wheel about 20 degrees to the left. I had the alignment done a few weeks ago and no digs. It stills pulls considerably although a little less.

The Carfax report is clean and the alignment guy said it didn't look like it had ever been in an accident.

What else could cause this?

[Garyo4]

Possibly either low air pressure in the front right tire or the brake caliber is sticking and the pads are scuffing enough against the right front rotor to cause your problem.

[Brother]

It has a tire pressure monitoring system, and I've messed with that, but the brake scuffing is something I haven't thought about.

How do you fix that?

[928ram]

Check for recall notices, there have been a couple Toyo recalls in the last year dealing with faulty suspension parts. I think it was mainly P/U trucks, but covered a couple million vehicles; might be the same components in the van.

[Brother]

I'll call the dealership. I bought it used, but it should still be covered.

[kaisen]

Most vehicles are built with a slight RH pull, so that it drifts off the road and not into oncoming traffic. Also, the crown of most roads will pull you gently to the right. Try the left-most lane of a divided highway and you may no longer drift right (because the crown will pull you left, may cancel the natural right-pull of the suspension setting).

E

[Brother]

This is excessive pull. I've driven all over the crown with the same results.

[BGCarrera32]

Dragging brake caliper or they fouled up the alignment. Make sure they cable or lock the steering wheel centered when they adjust the toe settings.

[singpilot]

Just pretend you are talking on the cell phone or reading the school paper the 5 unseatbelted kids in the back have just handed you. Then no one will notice you swerving all over the road in a minivan.

[Steve Carlton]

Could be a radial pull. Try switching the front tires.

[tabascobobcat]

Ask the alignment guy when the last time his equipment was calibrated. I actually saw a tech back a car off the lift with all the sensors still mounted to the wheels.
If it's not tire pressure, not the alignment and not a dragging brake (you would have likely burned the pads and rotor by now if it were) then it's most likely the tires like Steve said. The tires have a property called conicity (derived from the word conical). Basically the belt overlap can cause the thing to have a slight cone shape to them. Newer cars are ever more sensitive to this than were the older ones. If switching the front tires left to right doesn't work it may be the gear box, subframe, tire RCF or RAT, etc....

[Brother]

The van seems to tilt ever so slightly to one side. I haven't measured anything so it is just a guess. It is barely noticeable.

I'll swap sides with the front tires and see if that helps.

Would it be better to move the rear tires forward and then swap sides with the fronts. RF becomes LR and RR become RF.

[singpilot]

Ok, question of the hour. The most important question asked so far. I see you are in Texas, so the answer is even more important.

Does it lean to the left or the right?

If it leans left and goes right, then that is destiny (ask any Reagan Democrat).

If it leans right and goes right, that is the natural order of things.

[tabascobobcat]

That is a good hint about the lean.
Assuming that it has never been wrecked, your front springs might be a little different. Spring height is terribly difficult to control in the mfg process. I know of an OEM supplier who's internal spec is X +/- 16 mm. Normally, the front left and right springs are the same so the difference can be significant. If that is the case........hhmm.....toughie.
You can measure the resulting difference. Drop a tape measure from the top of the wheel well lip centered above the tire to the floor.

[kaisen]

Originally posted by tabascobobcat
That is a good hint about the lean.
Assuming that it has never been wrecked, your front springs might be a little different. Spring height is terribly difficult to control in the mfg process.

Nah. Didn't you read? It's a TOYOTA! Couldn't be manufacturing error. They are perfect.

E

[tabascobobcat]

Originally posted by kaisen
Nah. Didn't you read? It's a TOYOTA! Couldn't be manufacturing error. They are perfect.

E

My next idea is to get rid of it and buy a Honda.

[Steve Carlton]

Originally posted by Brother
Would it be better to move the rear tires forward and then swap sides with the fronts. RF becomes LR and RR become RF.

No, first you want to see if the pull is changed or reversed to isolate the problem.

[tabascobobcat]

Originally posted by kaisen
Most vehicles are built with a slight RH pull, so that it drifts off the road and not into oncoming traffic. Also, the crown of most roads will pull you gently to the right. Try the left-most lane of a divided highway and you may no longer drift right (because the crown will pull you left, may cancel the natural right-pull of the suspension setting).

E

Actually, Michelin enginners have told me that they design in a slight pull left into their tires to help offset the rh cant of the road surfaces. Road designs are normally about 2 degrees. Reduces customer complaints.

[legion]

I thought they designed their tires to rapidly depressurize?

[tabascobobcat]

Originally posted by tcar
So they must have different tires (tyres) for England, Japan, etc.?

I don't know for sure to be honest.
I never thought to ask. I will investigate tomorrow.