What Can Happen If Front And Back 225/40/18 Were Installed On Is250

[Apaulo]

I need some advice on my current situation. My wife had rear tires installed on her Lexus IS250 RWD in 2010, and I had not realized that they were all the same size until today.

The car should have 225/40/18 on the front and 255/40/18 on the rear. but the tire dealer installed 225/40/18 on the rear. I informed the tire dealer, where the rear tires were purchased, and they pretty much said, "What do you want us to do about it"?

I would like to know, what possible damage could have been done to my wife's car?

Is it dangerous?

Would the tires wear faster?

Could it cause suspension damage?

Decreased miles per gallon?

I do not know a lot about cars, so any advice would be greatly appreciated.

Thanks in advance.

IS 250 year 2007

[LEX-SV]

Wow, some kind of tire dealer, best to avoid them in future. They should know better to say the least.

It's not a disaster. Tire diameter is about 0.6" less than correct tire, so expect slight improvement in acceleration and a slight decrease in gas mileage (effect is similar to slightly lower gearing). No suspension damage will result, but the rear tires will probably wear somewhat faster than correct tires. The ideal rim width for that tire is 8.0", but a range of 7.5" to 9.0" is acceptable, so no danger. I think your stock rear rim width is 8.5".

[Apaulo]

Thank you for your reply. I was worried that there might be some kind of damage to the car itself.

I went back to the dealer, and they are installing the correct size now; I just have to pay the labor and miscellaneous fees.

Thanks again!

[LEX-SV]

Thank you for your reply. I was worried that there might be some kind of damage to the car itself.

I went back to the dealer, and they are installing the correct size now; I just have to pay the labor and miscellaneous fees.

Thanks again!

No need to fear damage to car. But if you want the car to perform as designed and the rear tires to wear somewhat longer, the correct sizing is preferred.

Glad the tire dealer came to a reasonable solution, without high additional cost for you.

Thanks for letting us know outcome.

[reyoasian]

No problem with running square on RWD with staggered stock setup

For folks in Canada, they should be running square setup for snow tires in winter to balance traction front-and-rear

You have slight (negligible) differences in mileage and odometer reading but no biggie

[sktn77a]

There is no problem running the same size tires on the rear IF the wheels are the same size. The 18" rear wheels on the IS250 are wider than the front wheels. I wouldn't want to run 225 on them (the stretched fit on the rear, relative to the front,will cause strange handling) and the tire dealer knew that, too, hence the offer to replace them with the correct size tire essentially for free.

[tex2670]

I need some advice on my current situation. My wife had rear tires installed on her Lexus IS250 RWD in 2010, and I had not realized that they were all the same size until today.

The car should have 225/40/18 on the front and 255/40/18 on the rear. but the tire dealer installed 225/40/18 on the rear. I informed the tire dealer, where the rear tires were purchased, and they pretty much said, "What do you want us to do about it"?

I would like to know, what possible damage could have been done to my wife's car?

Is it dangerous?

Would the tires wear faster?

Could it cause suspension damage?

Decreased miles per gallon?

I do not know a lot about cars, so any advice would be greatly appreciated.

Thanks in advance.

IS 250 year 2007

Thanks for the bump--sorry I'm late to the game. I wish I saw this thread in September.

What do you want the tire store to do about it? Order the correct f--in' tires and install them at the dealer's cost. Pretty basic....