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Look at the sidewalls carefully. They are not rated at 40psi. 40psi is likely the maximum air pressure that should be used with this tire. Those tires are not making full tread contact based on your dust marks. They're either inflated too much and/or the rim is too narrow for the tire.
 

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Look at the sidewalls carefully. They are not rated at 40psi. 40psi is likely the maximum air pressure that should be used with this tire. Those tires are not making full tread contact based on your dust marks. They're either inflated too much and/or the rim is too narrow for the tire.
I think Im not being clear. I run high PSI when driving on the highway. When Im out making passes I lower the pressure to 20psi. At 18-20psi after a burn out you can feel that almost the whole tire is making contact with the pavement.
 

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Discussion Starter #23
The Nittos are stock size .... same as the orig goodyears

right from my bill:

"40586 1 2 P 285 /40 R18 96Z SL BSW 303.67 .00 607.34 WDGA01 WDGA01"

Regarding air pressure I will look at that tonight. Car is in the garage and will check that.

Since I dont go to the strip ..... Im thinking 30-35 PSI for everyday driving and occasional spirited starts ?

don
 

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Discussion Starter #24
And some of the posters indicated they would have gone for the larger size but I
felt the tire was too tall

That said definite better grip but I only jumped on it twice .... still cool here in
florida so on a hot summer day I think the traction will be better.

don
 

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I looked it up. A NT05R in285/40-18 gives a spec of 1,565 lbs. at 44 psi. So for 4 tires, you're looking at a load rating of 6,260 lbs. at the maximum load rating of 44 psi. If you took your GVW of 4,700 lbs., you're at about 75% of load capacity. 75% of 44 psi. is 33 psi. Your range of 30-35 would be in the ball park.
 

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Discussion Starter #26
good news !!

don
 

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I run a different size 315/35/20 on a 20x11 but like 26-28psi on the street and 15-17 at the strip.
I'm happy for my use, plus they match the front tires.
-J
 

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Hey Don, I know this is an old thread but I also know you’re still around the forum. What do you think of the NTO5r’s you had put on?
 

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Hey Don, I know this is an old thread but I also know you’re still around the forum. What do you think of the NTO5r’s you had put on?
Thread closed due to age. Please start a new one with your question Ron.
 
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