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Discussion Starter #1
Morning Stangers! :wavey

I have an usual question:

Two days ago I put new rear tires on my car 305-35-19 Mickey Thompson's on a 19x10 wheel. Well, my front are 255-35-19 on a 19x9 wheel. It seems that when I am driving (at high speeds 70+), the car is very sensitive to wheel turning. Is this caused by the large difference in tire width between the rears and the front? Before the rears were 285-35-19 NITTO INVO's.
 
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Not only do you have a large difference in tire width but also a large difference in overall hight and diameter, 26"f vs 27.4"r. Obviously first thing to check is wheel balance and alignment.
 

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Are you driving with all the nannies turned off? That's a fairly large difference in rpm(rotations per MILE). The wiggle may be from the rotor retainer clips:bigthumbsup, or a tire that's out of balance or has a higher than normal roadforce reading.
 

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Not only do you have a large difference in tire width but also a large difference in overall hight and diameter, 26"f vs 27.4"r. Obviously first thing to check is wheel balance and alignment.
I will be checking those two things at some point this week. Perhaps I should purchase a new front tire? Maybe 265-35-19's? Which brand though?
 

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I will be checking those two things at some point this week. Perhaps I should purchase a new front tire? Maybe 265-35-19's? Which brand though?
A 275/40/19 would be very close in size. Are you certain the rotor retainer clips have been removed from all 4 rotors?
 

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Not only do you have a large difference in tire width but also a large difference in overall hight and diameter, 26"f vs 27.4"r. Obviously first thing to check is wheel balance and alignment.
Not to mention a huge difference in tread and performance characteristics. When I put my MT's on I drive slowly and carefully to the track. But, I may be overcautious:yup:
 

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Everyone in the thread mentioned great things...especially the tire height. That was the number one thing I measured when purchasing my tires. I wanted everything as even as possible.

Also you may needs some hub rings. That rear wheel bore might be very large and is wobbling a little. Hub rings make a world of difference on wheel fitment and road manners....and they cost only $5 from Discount Tire.:bigthumbsup
 

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Discussion Starter #8
A 275/40/19 would be very close in size. Are you certain the rotor retainer clips have been removed from all 4 rotors?
Mannnnn! I didn't know anything about the retainer clips!! I will try that first and see how it is. Thank you! :worship
 

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If you do find that your going to balance the tires go for road force as I thing it is a bit better than just spin.
 
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Is "road force" a certain way of getting the tires balanced? :im confused:

Yes, a roadforce balance machine has a drum that gets pressed down on the tire with great force while it is spun. This looks for imperfections on the tire itself that can show up as a vibration even when the wheel/tire is balanced. If an imperfection is found the tech dismounts the tire off the wheel and rotates it usually 90 degrees and remounts. This is done as many times as it takes to get the roadforce below a certain threshold.
 

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Yes, a roadforce balance machine has a drum that gets pressed down on the tire with great force while it is spun. This looks for imperfections on the tire itself that can show up as a vibration even when the wheel/tire is balanced. If an imperfection is found the tech dismounts the tire off the wheel and rotates it usually 90 degrees and remounts. This is done as many times as it takes to get the roadforce below a certain threshold.
Cool! I will look into this. Thanks!:bigthumbsup
 

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Yes, a roadforce balance machine has a drum that gets pressed down on the tire with great force while it is spun. This looks for imperfections on the tire itself that can show up as a vibration even when the wheel/tire is balanced. If an imperfection is found the tech dismounts the tire off the wheel and rotates it usually 90 degrees and remounts. This is done as many times as it takes to get the roadforce below a certain threshold.
Our roadforce would make you mark the rim and tire and certain spots, then dismount and aling the 2 marks, then re-roadforce, if it still had a reading above ~30?, the tire would be determined as faulty. I had a vibration issue on my 08 GT when new, that would only show up once the tires were "warm"... The roadforce was high on that tire, but not over threshhold for warranty replacement, I told the tech to take it out and warm them up, and then recheck the roadforce, and the roadforce number moved up over 10 points, and that tire was replaced under warranty... Roadforce will also check for rim runout and roundness:bigthumbsup.
 
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Our roadforce would make you mark the rim and tire and certain spots, then dismount and aling the 2 marks, then re-roadforce, if it still had a reading above ~30?, the tire would be determined as faulty. I had a vibration issue on my 08 GT when new, that would only show up once the tires were "warm"... The roadforce was high on that tire, but not over threshhold for warranty replacement, I told the tech to take it out and warm them up, and then recheck the roadforce, and the roadforce number moved up over 10 points, and that tire was replaced under warranty... Roadforce will also check for rim runout and roundness:bigthumbsup.

Yeah our machine is a Hunter GSP9712(just looked) and has a threshold of 30lbs but really anything over 10-15lbs is very noticeable when driving especially at highway speeds. For car tires this is almost no concern at all but when you start working on truck and suv tires it starts to become tiresome.

Brand new car tires are almost always under 5lbs and not even worth roadforce balancing, however this may be due to us only using premium tires from Michelin and Continental. I won't sell Pirellis anymore even if the car came stock with them though that's mostly due to low tread life. Pirelli Scorpion truck/suv tires are pure bovine excrement. It can make a Mercedes ride like a dumptruck going down a gravel road and they came stock on the GL-550.

Goodyears other than LS2(stock on my Audi) also tend to be very rough. I won't even get into the cheap tires like Nexen and Kumho.
 

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Yeah our machine is a Hunter GSP9712(just looked) and has a threshold of 30lbs but really anything over 10-15lbs is very noticeable when driving especially at highway speeds. For car tires this is almost no concern at all but when you start working on truck and suv tires it starts to become tiresome.

Brand new car tires are almost always under 5lbs and not even worth roadforce balancing, however this may be due to us only using premium tires from Michelin and Continental. I won't sell Pirellis anymore even if the car came stock with them though that's mostly due to low tread life. Pirelli Scorpion truck/suv tires are pure bovine excrement. It can make a Mercedes ride like a dumptruck going down a gravel road and they came stock on the GL-550.

Goodyears other than LS2(stock on my Audi) also tend to be very rough. I won't even get into the cheap tires like Nexen and Kumho.
I couldn't remember the exact #'s, but what was interesting was the fact that BFGoodrich wouldn't warranty the tire unless it "roadforced" a certain number. The other tire/rims were very low, they even pulled 4 off of another car, and all 4 of those tested very low as well. I then advised the tech about how it's worse when they are hot. Car had 400 miles at initial concern, resolved at 800 miles. That was a cheap shot at my tires Grimace:soembarrassed(no pun intended:didnotdoit:). My Kuhmo's flat spot every night:hihi:....... But grip like:worship....
 
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I couldn't remember the exact #'s, but what was interesting was the fact that BFGoodrich wouldn't warranty the tire unless it "roadforced" a certain number. The other tire/rims were very low, they even pulled 4 off of another car, and all 4 of those tested very low as well. I then advised the tech about how it's worse when they are hot. Car had 400 miles at initial concern, resolved at 800 miles. That was a cheap shot at my tires Grimace:soembarrassed(no pun intended:didnotdoit:). My Kuhmo's flat spot every night:hihi:....... But grip like:worship....
HAHA no cheap shot intended! Was just going by what I have experienced here at work. It baffles me when a customer rolls in with a $60,000 car and $125 tires. I'm sure Kumho can make decent tires, just like Michelin can and has made some really crappy tires(Pilot Sport 1).

I haven't warrantied a tire because of roadforce yet but I do believe there is a number they need before they will go ahead and replace it.
 
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