Does anyone know if it would hurt my truck's differential to run a smaller spare tire on the back wheels til I get my flat tire fixed. I run 20's but my spare is a 17 I think. Not sure but I can verify. Just wondering.
Smaller spare tire do any harm?
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Is the outside diameter of the tire the same?
what are both sizes? go to miata.net's garage and plug them into the diameter calculator, or just roll the spare over next to a good tire and see if they're close.
Limited slip would have a problem, open, not so much, but it might handle funny or the ABS would complain.
If both the spare and your regular tires are stock it should go good.
Limited slip would have a problem, open, not so much, but it might handle funny or the ABS would complain.
If both the spare and your regular tires are stock it should go good.
Originally Posted By: eljefino
Limited slip would have a problem, open, not so much, but it might handle funny or the ABS would complain.
If both the spare and your regular tires are stock it should go good.
Agreed on all points.
In addition to ABS, stability control might have an issue as well but I have no idea if your truck has such a system.
But again, none of this is a problem if everything is stock or has the same overall diameter as the stock part.
Limited slip would have a problem, open, not so much, but it might handle funny or the ABS would complain.
If both the spare and your regular tires are stock it should go good.
Agreed on all points.
In addition to ABS, stability control might have an issue as well but I have no idea if your truck has such a system.
But again, none of this is a problem if everything is stock or has the same overall diameter as the stock part.
Originally Posted By: pgun67
I run 20's but my spare is a 17 I think.
Rim diameter doesn't tell the whole story. We need to know the exact tire sizes to determine if the outside diameter is different.
I run 20's but my spare is a 17 I think.
Rim diameter doesn't tell the whole story. We need to know the exact tire sizes to determine if the outside diameter is different.
A significant difference in the outside diameter of the tire (more than 1/2") will cause the differential to seriously overheat. If the difference is 1/2" or greater, then run at no more than 50 mph, and for no more than 50 miles. Then allow the diff to cool for at least 2 hours, preferably more, before doing it again.
Originally Posted By: Reddy45
Put the non-matched tires on the front. It is cheaper to replace a hub/rotor than to replace a burnt up differential.
I know this because this is how my truck is currently set up. My spare tire is a different size from my normal ones.
I agree.
Honda S2000 comes with compact spare tire, Honda recommends if you have a flat rear tire you should replace the front tire with the spare and use the front to replace the rear.
Put the non-matched tires on the front. It is cheaper to replace a hub/rotor than to replace a burnt up differential.
I know this because this is how my truck is currently set up. My spare tire is a different size from my normal ones.
I agree.
Honda S2000 comes with compact spare tire, Honda recommends if you have a flat rear tire you should replace the front tire with the spare and use the front to replace the rear.
Kestas
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I too agree. I understand the spare tire should go on the non-differential axle. More than once I had to do two tire changes for one flat, so the space-saver spare went on the non-drive axle.
Yet another reason why I'm not a fan of having these oversized and overpriced wheels and tires on anything... factory OR aftermarket.
My factory spare on my Silverado just happens to be the same size and diameter as the four tires and wheels that are on the ground.
So simple, isn't it?
My factory spare on my Silverado just happens to be the same size and diameter as the four tires and wheels that are on the ground.
So simple, isn't it?
Originally Posted By: mrsilv04
Yet another reason why I'm not a fan of having these oversized and overpriced wheels and tires on anything... factory OR aftermarket.
My factory spare on my Silverado just happens to be the same size and diameter as the four tires and wheels that are on the ground.
So simple, isn't it?
LOL. This.
Or, buy a 5th aftermarket wheel/tire so that you can have a "spare" that doesn't look like a spare, and you can also do a 5-tire rotation.
Yet another reason why I'm not a fan of having these oversized and overpriced wheels and tires on anything... factory OR aftermarket.
My factory spare on my Silverado just happens to be the same size and diameter as the four tires and wheels that are on the ground.
So simple, isn't it?
LOL. This.
Or, buy a 5th aftermarket wheel/tire so that you can have a "spare" that doesn't look like a spare, and you can also do a 5-tire rotation.
I would actually wonder. I am suspecting your truck has the G80 locking differential. If the spare tire is significantly different in circumference than the regular wheel/tire combo it could try locking up the differential...
Does anyone know which rear tire gets the power from the differential? Driver or passenger side on a 2000 silverado, auto, 5.3L??
I always thought only one tire was powered from the diff and if that tire slipped and lost traction then the locking part would engage the other tire to get traction. I thought only a posi trac had both wheels powered from the diff at all times.
Nope. Even open diffs send the power to both wheels at all times -- again, as long as both wheels have traction. The only time you get the power going to one wheel is when that wheel is off the ground or slipping, because the power always takes the path of least resistance. However, that will happen whether it's the left or the right wheel that is slipping.
Limited-slip differentials prevent one wheel from spinning too much faster than the other, hence the term "limited slip." This makes sure that both wheels get at least some power, even in the worst conditions.
Lockers obviously lock both wheels together.
Gear-type torque biasing diffs naturally send more torque to the slower-spinning wheel, but with a catch: if one wheel is entirely off the ground, it behaves like an open diff and just spins the wheel with no traction.
Limited-slip differentials prevent one wheel from spinning too much faster than the other, hence the term "limited slip." This makes sure that both wheels get at least some power, even in the worst conditions.
Lockers obviously lock both wheels together.
Gear-type torque biasing diffs naturally send more torque to the slower-spinning wheel, but with a catch: if one wheel is entirely off the ground, it behaves like an open diff and just spins the wheel with no traction.
Originally Posted By: pgun67
Does anyone know if it would hurt my truck's differential to run a smaller spare tire on the back wheels til I get my flat tire fixed.
Nope, wouldn't hurt a thing. As d00df00d explained how the diff works the power will go to both wheels equally unless one is slipping.
But that GIANT pic of your truck in your sig... now that's hurting my eyes! Smallify that guy, please!
Does anyone know if it would hurt my truck's differential to run a smaller spare tire on the back wheels til I get my flat tire fixed.
Nope, wouldn't hurt a thing. As d00df00d explained how the diff works the power will go to both wheels equally unless one is slipping.
But that GIANT pic of your truck in your sig... now that's hurting my eyes! Smallify that guy, please!
Originally Posted By: Reddy45
Put the non-matched tires on the front. It is cheaper to replace a hub/rotor than to replace a burnt up differential.
I know this because this is how my truck is currently set up. My spare tire is a different size from my normal ones.
Agreed. Really it is all you can do. That or just do not drive it/have it towed. I personally would not drive it much at all unless the overall diameter was at least somewhat close.
One other note of importance. If the truck is a 4WD be sure you do NOT engage it with different sized tires or you can toast the front diff. You really need to match your spare up to your regular wheels.
As others have said though what matters is overall diamter not rim size. You can run a 17" wheel and still match up size wise with the 20's you have at the 4 corners. I wiill use my truck as an example to explain to you...
I actually have 20's now and want to downsize to 17's. I hate the ride 20's give you plus they are sort of wide and that results in poor snow traction. The stock 20's on my truck are 275/60R-20 which is an overall diameter of 32.99 inches. I can downsize to a 285/70R-17 tire which has an overall diameter of 32.70 inches. Not exact but very close. My speedo won't be off much and my 20" spare can be used, with caution, safely if I don't have the extra $$$ to swap the spare when I do the 4 drive tires. Eventually I would swap the spare over too.
So the moral is you can have multiple tire sizes that are almost identical in overall diameter.
Put the non-matched tires on the front. It is cheaper to replace a hub/rotor than to replace a burnt up differential.
I know this because this is how my truck is currently set up. My spare tire is a different size from my normal ones.
Agreed. Really it is all you can do. That or just do not drive it/have it towed. I personally would not drive it much at all unless the overall diameter was at least somewhat close.
One other note of importance. If the truck is a 4WD be sure you do NOT engage it with different sized tires or you can toast the front diff. You really need to match your spare up to your regular wheels.
As others have said though what matters is overall diamter not rim size. You can run a 17" wheel and still match up size wise with the 20's you have at the 4 corners. I wiill use my truck as an example to explain to you...
I actually have 20's now and want to downsize to 17's. I hate the ride 20's give you plus they are sort of wide and that results in poor snow traction. The stock 20's on my truck are 275/60R-20 which is an overall diameter of 32.99 inches. I can downsize to a 285/70R-17 tire which has an overall diameter of 32.70 inches. Not exact but very close. My speedo won't be off much and my 20" spare can be used, with caution, safely if I don't have the extra $$$ to swap the spare when I do the 4 drive tires. Eventually I would swap the spare over too.
So the moral is you can have multiple tire sizes that are almost identical in overall diameter.
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