lexman52

Can someone please tell me what the PSI is on tire size 245 45 18. I can't seem to get a definite answer from anyplace Had new tires put on recently and 1 tire was 36psi 2 tires 40psi 1 tire 45psi. Called and was told to just make them all the same??

tradosauru

See attachment from owners manual on recommended tire inflation pressure.

Should be 33 psi all the way around. Check your tire pressure when the tires are cold.

I've been on ecomodder forum where the idea was to maximize your mpg's and guys were inflating their tires to 45 psi. The reason I wouldn't do this is the risk of wearing expensive tires on the side treads instead of uniformly.

SW17LS

Not to mention there is a huge ride penalty at high PSI

z2g2gs

There is always a debate on tire pressure. Auto manufacturer recommendation or the tire manufacturer, type of driving or fuel mileage and so on. Recommended tire air pressure for the tire itself is on the sidewall of the tire and it varies from one maker to the next. It is always recommended to check cold. Also weather by season will have a effect. Get a dial or digital gauge and check yourself, keep them set all the same, don't trust the tech for this they are all in a hurry thinking a pound or two difference won't matter, maybe not but it does on my car. I personally like it a little on the firm side, not so much for milage which is nice, but for a good feel of the road. Always keep a visual inspection routine for wear.

SW17LS

This is incorrect and people commonly get this wrong. What is on the sidewall of the tire is not the "recommended pressure", its the maximum pressure. That is the maximum the tire can be inflated to and safely carry its max load.

Tire manufacturers will tell you to inflate the tires to the recommended pressure on the vehicle's door jamb or owners manual.

z2g2gs

My bad, you are correct. On the Michelin's on my car, sidewall does state max. pressure 50 psi. for the stated max. load. Door jam of the car shows 33 psi. cold. I am currently running 40 psi. cold which works great, good feel, no uneven wear. Thanks for the correction.

lexman52

I agree with the door jam but on the sport model is has the 17in tire psi not the 18in.

Lavrishevo

iTrader: (1)

I run 34 - 35 psi personally. Going too high transfers extra abuse to the suspension.

z2g2gs

Another bit of information for consideration. This is from the Michelin web site, which does recommended following auto maker recommendation. On my 08 GS350 it is 33 psi cold.







Just my opinion I guess but I feel the recommended 33 psi is a bit soft. This is for the ride Lexus is looking for that we all love and enjoy, but not so much for maximum tire life. As I stated in my first post it is a debate that will be on going.

Tom57

Going too high transfers extra abuse to the occupants as well. Higher tire pressure also results in tire wear down the middle of the tread, and less traction. I run 35 psi on both LSs with 18s and the LS with 17s.

Lavrishevo

iTrader: (1)

Your not going to hurt the tire whether you run 30 or 45 psi but the harshness of the ride will definitely go up with more pressure. When there is less give in the sidewall with high psi it transfers road imperfections to the suspension and therefore wears these components more quickly.

And extra abuse to your rear end like Tom mentioned

XJSFan

I run 35PSI...

Bocatrip

I have Primacy 17s that are V rated. I try keeping the pressures around 35 all around.

lexman52

Well 35PSI is it. Thanks

5t341th

iTrader: (16)

should tell you recommended tire pressure on the drivers side door jam