Car drifts to one side.

[pitts64]

I just had my car aligned and installed new Firestone Firehawk tires. I started noticing it was drifting to the right. I switched front tires side to side and now it drifts to the left.. What could make a new tire do this?


Thanks...

[David Pozzi]

Front tires?
On rear tires it can be a diameter difference.
On the front I have heard of chord angle differences that can do that.
David

[ErikLS2]

This can be quite common, even with new tires. Most high end wheel balancers have a function on them that show's placement of the tires for minimal pulling. It presses a large roller onto the tire as it spins and measures imperfections in the tire. Here is a decent explanation of tire pull from Tire Rack, however, they incorrectly say that if you rotate the tires as you did and the pull doesn't change then the pull isn't caused by either one of those tires.

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=12


A good way to illustrate this is take an empty toilet paper roll and draw spiral lines on it like on a barber pole. Roll it on a table and watch the lines, they'll travel to the right or the left. Then, turn the roll over and do the same thing and you'll see the lines travel in the same direction. This same thing can happen with a tire and cause a pull in the same direction regardless of tire position (although not in your case as the car pulled the other way) . In your case, what you have is a tire "conicity" problem. This can be illustrated with a small styrofoam cup. Lay it on it's side and roll it on a table, it pulls to one side. Flip it over and you see that it pulls the other way. This is the kind of tire pull you have. Many times it can be used to cancel itself out by rotating the tire on the wheel (if non-directional) or less often by mounting the right front tire on the left wheel (rotating the same direction) and vice versa with the left front tire.

You've already narrowed the problem down to one of the front two tires but this can also be caused by a tire on the rear. Remember, the rear tires have a lot of directional input on the car so all this stuff can apply to them as well.

Most of our cars here have larger tires on the rear limiting us from moving the tires around on the car too much. If you happen to have all 4 of the same size tires you can probably eliminate the pull with the tires you have on there now by placing them correctly on the car. A tire balancing machine with the feature I mentioned above is the easiest way to do this. Many times new tires that exhibit a pull lose this tendency though after they have a couple thousand miles on them, other times they have to be replaced.

I've also heard hear-say by way of a Dunlop tire engineer that the best thing you can do for a modern radial tire is to rotate it on the car so it spins the other direction after no more than 5000 miles.

Sorry for such a long post, I've spent many hours moving tires around on a car to eliminate a pull caused by them. Hopefully this information is helpful. Good luck.

[pitts64]

The tires are all the same size (225/70-15).

How should I rotate them? I'm thinking criss cross with the offending right front tire on the rear left side....


When I bought them, they were balanced on the Road Force balancer, trouble is, the kid running the balancer didn't know what he was doing and the car vibrated at highway speeds. I had to have them balanced at another garage. He used a regular spin balancer and said they were all way off. Now they are vibration free.. The car never drifted after all this, it just started doing this last week after 500 miles or so...

Thank you...

[ErikLS2]

You can try following the steps on the TireRack website I posted but since it wasn't there from the start the tire causing it (one of the fronts) should be replaced.

A lot of tire places will not readily warranty a tire that does this but it is a defective tire. I guess you get to find out how good the customer service is wherever you bought the tires. You might have to make some noise.

[John Wright]

The tires are all the same size (225/70-15).

Did you take a tape measure and wrap the middle of each tire? Note that were any differences in diameter?(this is what David P was suggesting and might be the cause of your pulling)

I had a tire grow (belts in the tire were seperating) on my camper and on the way back from the beach it started rubbing the inside of the inner fender....set off all of the smoke detectors inside the camper.....I had people pulling along side motioning to me on the Interstate to pull over....LOL

[pitts64]

I'll try checking the diameter.. I'm going to try getting it replaced.

[monteboy84]

Did the pull intensity stay the same when you switched side to side?

You may want to speak to the alignment shop about re-checking your caster on both sides. Caster split of any kind will make the car pull to the side with less positive caster. Check your tires first, then look into the caster.

-matt

[pitts64]

It is the tires...

I rotated the offending tire to the opposite side rear. It seems fine now...

I'm going to try to get JT Tire (rt8 Allison Park, Pa) to replace it. But after at the horrible job they did balancing the tires, I'll bet the fight me but I'll try anyhow..

[exwestracer]

It is the tires...

I rotated the offending tire to the opposite side rear. It seems fine now...

I'm going to try to get JT Tire (rt8 Allison Park, Pa) to replace it. But after at the horrible job they did balancing the tires, I'll bet the fight me but I'll try anyhow..

Before you go in, make sure ALL 4 tires are inflated to mfrs suggested pressure (not max pressure). Drive the car and see how it handles. They probably won't do anything unless you can prove there is a problem, so you might put the "bad" tire back up front first.

[pitts64]

Hello guys, I'm having the same trouble all over again with the new tires I just bought but not as severe as with the Firestones, this time it's a slight drift not a severe right pull...

I just installed four Westlake SU307 235/70r15 tires on my car and it drifts to the right...

These tires seem like decent tires, they are H rated, I bought them for $70 each at Tireseasy.com..

Should I rotate them in an X front to rear or side to side?

Thanks for all your help!

[pitts64]

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[pitts64]

I ended up adding a 1/2 degree of negative camber .

[pitts64]

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