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Hey guys i got a question, i hit a pot hole the other day and unfortunataly blew out on of my front tires. I was wondering if i have to change all 4 of the tires because of the all wheel drive system or if i would be okay just replacing the front two tires.

Thanks for any help
 

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+ or - 3% is what the transfer case can handle.
 

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The Traveler
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I had a similar question not to long ago. I believe the tire shop told me it had to be 3/32 or less difference between the tires. I was looking at replacing my front set only. I ended up doing all 4.
 

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Is that +/- 3% of the OD of the tire?

3/32 can't be right... that's nats hairs. My friend Josh told me the same thing about his Evo... but I have a very hard time believing that a vehicle's drivetrain can tell the difference of 3/32 in wheel rotation.

If the OD is 25", that means you have .75" to work with.
If the OD is 26", that means you have .78" to work with.

That's > the difference of a bald tire, to a brand new one.

Ie: The tread depth on a Nitto 555 is .33125" The Envo is .3125". That being said, you could have one down to the chords, and brand new ones on the rear, and it wouldn't matter.
 

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Is that +/- 3% of the OD of the tire?

3/32 can't be right... that's nats hairs. My friend Josh told me the same thing about his Evo... but I have a very hard time believing that a vehicle's drivetrain can tell the difference of 3/32 in wheel rotation.

If the OD is 25", that means you have .75" to work with.
If the OD is 26", that means you have .78" to work with.

That's > the difference of a bald tire, to a brand new one.

Ie: The tread depth on a Nitto 555 is .33125" The Envo is .3125". That being said, you could have one down to the chords, and brand new ones on the rear, and it wouldn't matter.
Do all the math you want. I'm am just giving the info that the SRT engineers gave at one of the chat sessions. You can use it or make your own judgment. :pinklove:
 

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The Traveler
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I had a similar question not to long ago. I believe the tire shop told me it had to be 3/32 or less difference between the tires. I was looking at replacing my front set only. I ended up doing all 4.
I believe the factory front good years are 12/32 new. My rears were at 7/32 left. They said no dice. I think they actually said 4/32 was the maximum difference. But I'd says stay 3/32 to be safe. But basically with a new tire and slighty better than half tire it wouldn't work.

I've read too many stories about mismatched tires and t case issues. I didn't want to be another statistic lol. Your decision. Just make an informed choice.
 

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The Traveler
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Do all the math you want. I'm am just giving the info that the SRT engineers gave at one of the chat sessions. You can use it or make your own judgment. :pinklove:
Maybe +/- 3% the original tread depth not the overall tire size.
 

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Yes... I'm saying that I'd agree with you about the 3%. That sounds like a good tolerance.
But... 3% of what? Precentages aren't useful unless you can multiply them by something to get your values.
I don't think that 3% = 3/32 of tread depth.
If it does, I would like someone to explain how.
 

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Maybe +/- 3% the original tread depth not the overall tire size.
No, this was in question to front and rear tires and whether the 275/315 combo would work. Still your choice.
 

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275/315 ? What does the tire width have to do with roation? As long as you get the right sidewall height so the % of rotation front-rear doesn't change... it should be ok.
I don't understand your "Still your choice" logic, when you're not giving any useful information.
 

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Yes... I'm saying that I'd agree with you about the 3%. That sounds like a good tolerance.
But... 3% of what? Precentages aren't useful unless you can multiply them by something to get your values.
I don't think that 3% = 3/32 of tread depth.
If it does, I would like someone to explain how.
This has nothing to do with tread depth measurements, it has to do with the circumference of the front and rear tires, + or - 3%. They need to be within + or - 3% from front circumference to rear circumference.
 
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while it's a good idea to have both tires on one axle close in tire wear, you can run different sized tires between the front & rear axles. the 3% quoted earlier refers to the entire diameter of the wheel & tire, so even if you're running brand new tires up front and a completely bald set in the back, the difference in diameter does not exceed the 3%.

the tire shop guys played you.
 

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This has nothing to do with tread depth measurements, it has to do with the circumference of the front and rear tires, + or - 3%. They need to be within + or - 3% from front circumference to rear circumference.
Now you're makin' sense. Any idea what the circumference of the stock tires are? (w/ full tread?)

while it's a good idea to have both tires on one axle close in tire wear, you can run different sized tires between the front & rear axles. the 3% quoted earlier refers to the entire diameter of the wheel & tire, so even if you're running brand new tires up front and a completely bald set in the back, the difference in diameter does not exceed the 3%.
Based on the fact that the 3% is in regard to circumference, and not diameter. I disagree. CMN1, do you have the full writeup anywhere.

Circumference and diamater would calculate the same way when it comes to rotation.
 

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275/315 ? What does the tire width have to do with roation? As long as you get the right sidewall height so the % of rotation front-rear doesn't change... it should be ok.
I don't understand your "Still your choice" logic, when you're not giving any useful information.
They aren't the stock sizes. Sorry I didn't put the whole tire size down but you seem to get it now and you still can make your own decision on who or what you want to believe.
 
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Now you're makin' sense. Any idea what the circumference of the stock tires are? (w/ full tread?)

No, but I'm sure tire rack or goodyear would have those specs.
 

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cmn hit the nail on the head with the 3% referring to the wheel's circumference, not the diameter as i erroneously stated.

the difference between a brand new g/y emt and a worn down one does not exceed this limit. hence, according to the srt engs, it's within tolerance to run a brand new set in the front and a worn down set in the back. ofcourse, the closer you are to a 0% difference, the easier it is on the xfer case, but i'll leave that to whoever wants to drop two grand to buy 4 new shoes every time they need to replace one.
 

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OK... Going with the 3% of circumference tolerance...
Stock tires are 29" Dia. That's 91.06" Circumference. (29*Pi)
3% of 91.06 is 2.7318. 91.06-2.7318 gives you the minimum Circumference.
So you could go down to 88.3282 Circumference, which is a dia. of 28.13 (88.3282/Pi).

Meaning... You can have a maximum tread depth difference of .87"

Bringing us back to the conclusion, that the fronts (or rears) can be very bald, and the rear (or fronts) could be brand new, and you still wouldn't have the .87" difference. Meaning, as long as you do both fronts, or both rears, there wouldn't be a problem. Because without running an offroad tire, I don't think there's a tire out there with a .87" tread depth.
 

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This has nothing to do with tread depth measurements, it has to do with the circumference of the front and rear tires, + or - 3%. They need to be within + or - 3% from front circumference to rear circumference.
Yup exactly what I remember the SRT enginer say as well Chad!
 
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