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Discussion Starter · #1 ·
I am running 20" Nitto NT05R Rears and NT555R Fronts, the diameter of the fronts are 91" and on the rears 91 5/8" on OEM rims. Is the 5/8" variation acceptable? How picky should I get? This is the closest match I can get on 20"s for the Nittos. Is it acceptable to play with lower tire pressure in the rear vs front to get the diameters in line? Sorry for the newbie question!
 

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I am running 20" Nitto NT05R Rears and NT555R Fronts, the diameter of the fronts are 91" and on the rears 91 5/8" on OEM rims. Is the 5/8" variation acceptable? How picky should I get? This is the closest match I can get on 20"s for the Nittos. Is it acceptable to play with lower tire pressure in the rear vs front to get the diameters in line? Sorry for the newbie question!
The manual says 8mm of diameter or 1" in circumference , so 5/8" in the circumference is no problem. Some have used up to 1/2" of Diameter with out issue, but that is about the line.

From factory it the circumference difference between front and rear is about the same 5/8" 88.1" Front and 87.5" Rear.

It should be close, I assume 275/40 F and 315/35 R? If so No worries.
 

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Discussion Starter · #3 ·
Correct on size and thanks for the clarification. I meant circumference in the post vs diameter. Aim I correct in using air pressure to dial in further? Re it would make sense to have less air in the rear anyway. I'm thinking like 25 or 26 psi rear vs 29 front.
 

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Correct on size and thanks for the clarification. I meant circumference in the post vs diameter. Aim I correct in using air pressure to dial in further? Re it would make sense to have less air in the rear anyway. I'm thinking like 25 or 26 psi rear vs 29 front.
I can tell you 5/8 of an inch will not work!! i tried nitto 555R , height was 28.58 and the front were runflats IIRC they were 28.0x so maybe a half and inch difference ..it threw a code after 50 miles..
 

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Discussion Starter · #5 ·
I can tell you 5/8 of an inch will not work!! i tried nitto 555R , height was 28.58 and the front were runflats IIRC they were 28.0x so maybe a half and inch difference ..it threw a code after 50 miles..
The 5/8" was on the circumference not the height. I think the height differene is less than 1/4".
 
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