bobys

I was at Lexus service and they thought they'd give me a lesson, that I needed to replace all 4 tires at the same time on an AWD RX (2013). I'm missing the paperwork ATM, but I think it was about 3-4 difference between the fronts and the backs.

I have only ever had the vehicle serviced at the Lexus dealership since I've bought it. Oil Changes, tire rotations, etc.....

Is there any real evidence about potential damage to the drivetrain running with the disparity?

Or is it just a little hopping and skipping on the pavement when turning in parking lots?

And you know the most peculiar thing about this lesson, I've never put tires on this RX, the same dealer did. I bought it CPO at about 33K miles. They said they replaced two tires on it and I didn't know about the AWD rule to spot this issue when I bought it.

Thoughts?

salimshah

Take this issue to the service dept manager.... specially if the same service department prepared and signed off the vehicle at CPO.

There will never be 4 identical tires. All systems work with certain tolerance. One should [key word being should] not try to skew the difference.

Salim

lexusrus

Maybe do an internet search with your VIN and see what comes up? Maybe you will get lucky and the pics (tires) as advertised (at the time when you bought it) will pop up?

Good luck.

ukrkoz

Not sure what 3-4 difference is? 3/4 of inch? That's a lot of difference then.
about 3-4 difference between the fronts and the backs.

AWD is NOT 4WD. For any drive system, engaging all vehicle wheels, concern is with outside tires diameter front to rear. As different diameter tires spin at different speeds for the mph.
In 4WD, you WILL have transfer case locked, if tires diameters do not approximate front to rear. In AWD, there is not really a direct mechanical need for exactly same tire RPMs front to rear, unless your differential is locked.
That said, you drive in FWD for about 90% of the time. You may get into AWD winter time or in rains and puddles, slippery conditions.

Not asking, how it ended being significant discrepancy front to rear. Tires never rotated, likely.

bobys

ukrkoz,

3-4 / 32s of an inch difference between fronts and backs.

Maybe I jumbled up the info. I'll try again.

I purchased "L/Certified" (CPO). The sales person said that two new tires were installed on the RX 350 AWD. Only 2.

I've taken the vehicle to the Lexus Dealership service department every 6 months. I would hope that they actually rotated tires as should have been appropriate. Plus, they should know that two different wear tires were on the vehicle, this was the exact same Lexus dealer for purchase and all service (since I purchased it from them).

Service said I could have caused excessive wear/damage to drivetrain by running car with different tread depths. But they put the two tires on before I purchased, they performed all the service.

Is there truth to this drivetrain claim they have made of potential damage?