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Old 08-16-2011, 07:40 PM   #1
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Dangerous to run tires backwards?

I know it's not a good idea, but is it dangerous to run your directions tires in the wrong direction?

'03 Base, 84k miles, put 3 new Nitto 555s on last fall, two front, and driver rear. Passenger rear had about 70% so the guy at Discount Tire said it did not need to be replaced. Recently was at the dealer twice for an alignment (car pulls to right). The second time, after they couldn't correct the situation, they flip flopped the front tires. Problem went away - car tracked straight. They said the tire was defective. Well after 9 months I don't think they are going to give me new tires. It was suggested that I dismount the tires and switch the left with the right Well that's $50 and maybe money well spent or maybe it won 't make a difference. I just want to move the left tire to the right and vice versa.

I dont' drive the car very hard, basically I use it for a short commute on nice days and the occasional country drive on the weekends. See any problems? I don't drive when it's wet out, so if tracking in the rain is a concern, that won't affect me. Am I missing something here or should I be okay.

And maybe it's not the tires, but my 8+ year old suspension is worn out? or ???

Sorry for the long post.

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Old 08-16-2011, 08:02 PM   #2
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I don't know if it is dangerous, maybe others know. I do know that with asymmetrical tires like the Sumitomo HTR Z III one half of the tire is kind of all season and the other directional. Well since they don't make a left and right tire one side always has the 'directional' part running backwards. This is true because they are labeled with an 'outside'.

Regarding the pulling...on my Benz I have the HTR Z III and they are awesome tires...BUT one was defective and whichever side the bad tire is on it pulls in that direction. Likely I guess one tire is a little bigger then the other. I got them at TireRack and should have fought to get my money back...kind of late now since they have 16k miles on them.

If you got your tires from Discountire they probably would replace them, they generally are a very well run company.
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Old 08-16-2011, 08:36 PM   #3
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Quote:
Originally Posted by Gforrest2
I know it's not a good idea, but is it dangerous to run your directions tires in the wrong direction?

'03 Base, 84k miles, put 3 new Nitto 555s on last fall, two front, and driver rear. Passenger rear had about 70% so the guy at Discount Tire said it did not need to be replaced. Recently was at the dealer twice for an alignment (car pulls to right). The second time, after they couldn't correct the situation, they flip flopped the front tires. Problem went away - car tracked straight. They said the tire was defective. Well after 9 months I don't think they are going to give me new tires. It was suggested that I dismount the tires and switch the left with the right Well that's $50 and maybe money well spent or maybe it won 't make a difference. I just want to move the left tire to the right and vice versa.

I dont' drive the car very hard, basically I use it for a short commute on nice days and the occasional country drive on the weekends. See any problems? I don't drive when it's wet out, so if tracking in the rain is a concern, that won't affect me. Am I missing something here or should I be okay.

And maybe it's not the tires, but my 8+ year old suspension is worn out? or ???

Sorry for the long post.
Among other things, it"s for water evacuation. Don"t drive on wet roads with the tires backwards, seriously dangerous at speed. Save $50 somewhere else.

Last edited by blue2000s; 08-16-2011 at 08:42 PM.
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Old 08-16-2011, 08:41 PM   #4
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Quote:
Originally Posted by WhipE350
I don't know if it is dangerous, maybe others know. I do know that with asymmetrical tires like the Sumitomo HTR Z III one half of the tire is kind of all season and the other directional. Well since they don't make a left and right tire one side always has the 'directional' part running backwards. This is true because they are labeled with an 'outside'.
Don't think that the HTRZIII is anything close to an all season tire. They're way too hard when cold. The different sections are for predictable, stable handling in combination with safe water removal.

Last edited by blue2000s; 08-16-2011 at 08:46 PM.
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Old 08-16-2011, 08:45 PM   #5
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Quote:
Originally Posted by blue2000s
Among other things, it"s for water evacuation. Don"t drive on wet roads with the tires backwards, seriously dangerous at speed. Save $50 somewhere else.
+1
There are some tires that are structurally directional but for our cars it's all about rain. Directional tires hydroplane easily if run backwards.
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Old 08-16-2011, 09:15 PM   #6
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Directional tires are designed to throw water to the outside rather than under the car.

Reverse them, and you're throwing the water under the car to the opposite wheel encouraging hydroplaning.

Not an issue if you don't drive on less than sunny days.

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Old 08-17-2011, 07:06 AM   #7
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Originally Posted by Lil bastard
Directional tires are designed to throw water to the outside rather than under the car.

Reverse them, and you're throwing the water under the car to the opposite wheel encouraging hydroplaning.

Not an issue if you don't drive on less than sunny days.

Cheers!
That might be true with some non-directional tires, but with these and all other directional tires the grooves are basically v's from the centerline out. Water is pumped out to both sides of the tire. If they're reversed, water is pumped into the center of the tire, making a nice thick puddle to slide on. There's no specific in side or out side on a directional tire, so they have to evacuate water equally to both sides. Otherwise you'd have to buy "right" side and "left" side directional tires.
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Old 08-17-2011, 12:45 PM   #8
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The vehicle response to running one new and one old tire in the rear is somewhat unpredictable. After several thousand miles, this may have caused the fronts to wear differently causing the pull. Flipping the fronts may have brought back balance - for the time being.

At this point, running the front tires backwards only introduces more unknowns which can't be easily sorted out.

You need to get back to a stable tire configuration if you want to be able to diagnose and ultimately solve the problem. Any decent mechanic will tell you to first replace all four tires, second get the tires balanced, and third, get a good alignment.

Odds are that your problem will be solved with this regimen. If not, then a bent wheel or suspension component is the next logical place to investigate.
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Old 08-17-2011, 05:32 PM   #9
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Quote:
Originally Posted by blue2000s
Don't think that the HTRZIII is anything close to an all season tire. They're way too hard when cold. The different sections are for predictable, stable handling in combination with safe water removal.
True they certainly aren't all season, I've driven several winters in them and I don't 'do' snow. But putting aside whatever the inner tread pattern is, the outer tread looks very much directional and one is always going in a direction that seems backwards. I have heard that some tire manufactures (but I haven't seen one) make a left and right so that this doesn't occur.
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Old 08-17-2011, 06:34 PM   #10
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Quote:
Originally Posted by WhipE350
True they certainly aren't all season, I've driven several winters in them and I don't 'do' snow. But putting aside whatever the inner tread pattern is, the outer tread looks very much directional and one is always going in a direction that seems backwards. I have heard that some tire manufactures (but I haven't seen one) make a left and right so that this doesn't occur.
I think Pirelli sold left and right tires for a while. Long ago.

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