Hi, I am new here so bear with me. I have a 2015 GX 460. I have a set of tires that measure between 7/32 and 8/32. I recently damaged a tire and the store told me that because of the AWD I need to buy 4 tires. I called a mechanic and the local Lexus dealer who told me that as long as the tread on the old tires were not less than 1/2 of the new tire, that I would be OK. They also told me to place the new tire on the passenger rear. The new tire is 12/32 so not more than 1/2. But, most of what I have read on the internet sides with the tore shop. Who is right? Thanks in advance.

 

Look for used tires same brand as you have now. They sell almost new tires in 1/5 -1/3 of the price. +$5-10 for installing and balancing. But you will need to change 2 tires otherwise it will be difference in depth therefore car will be unstable when braking or in slippery road.
I just spent $150 (incl. Install and balancing) for two bridgestown stock tires in almost new condition.
Remaining good tire you can save as spare one. I don't know what kind of mechanic would recommend to change just 1 tire...

 

Outside of the AWD consideration ... always replace tires in pairs ...on the same axle ... given it is important that both tires behave the same, especially in an emergency maneuver.

 

Sorry I wasn't clear. The mechanic didn't recommend that I change only one tire. He just said that it wouldn't be a danger to the transfer case or differential if I only changed one. Lexus said the same.

 

Great post! I recently had one bad tire but was told I would have to replace all 4. But I did have 40 k on those Michelins which were from factory. They could have been more than 1/2 of the tread of a new one with that many miles on them. Nothing was said about comparing the tread to a new one. I wish I would have seen this a couple of months ago!

 

Just to update. I talked to a different Lexus Tech. This time factory direct. He said that German made AWD drive cars are notorious for the problems the tire shop described. But, that Lexus vehicles are not that sensitive and while I may experience a slight pull until the new tire wears down a bit, I am perfectly safe replacing only one.

 

You really haven't given us enough information to give you a proper answer, but the German/Lexus difference is ridiculous.

Will you be replacing with the identical tire?
What is the date code on your current tires?
How many miles are on your tires?

Here are a few considerations

A tire is considered legally worn at 2/32nds, but in actuality, a tire is no longer safe in wet weather.
Your single solitary tire will always have 5/32nds more tread than your other three tires. As your other tires get closer to 4/32nds, the grip on that on that one tire will be different.
If you change only one tire, then you'll need to change 3 tires in a couple of years. A year or so later you'll have to change one tire.

While your car won't blow up if you only get one tire, your handling may be compromised in iffy conditions (where you need it most) but it is also fiscally unsound.

If you buy two tires then you'll always have a matched pair and, with proper rotation, you'll not need to change tires for a long time.

 

Can you just use your spare on one and get one replacement the move the worn tire to the spare location? I would replace a pair instead of just 1 tire if the spare isn't a match.

 

 

You can have tires shaved last I looked, which was years ago. I was told--and this was on a 2003 Honda Element in about 2010--that 1/32 inch is the limit their shop recommended for tire depth difference if they were to replace just one or two tires. They offered to shave a couple of new ones. Instead, I just bought a whole new set at the time. Tires are critical. We ignore them too much.

 

amen to this.

But to the OP, I think there is good advice here for replacing, at minimum, two tires at a time.

Interesting comment you were told about German AWD systems. I have an older (2007) AWD BMW 530 and I had some strange stability/handling issues when I only replaced two tires instead of all four. In more stressful driving situation (e.g cornering at higher speeds) I would sometimes experience the traction control activating at odd times and actually making the car feel less stable. These issues went away completely when I replaced the other two tires. Perhaps the electronic systems in some makes/models are more sensitive to different tread depths.

 

If it was my GX, I'd either replace one tire, or run the spare, and then buy 4 new tires when the other 3 were finally ready.

 

The viscous-coupling based & all mechanical AWD system (Borg Warner 4404) I had in an old Ford Explorer ('96 5.0L) would ultimately fail if mismatched tread depths were used. Mine was always reliable but lots of reports of failed units. A different setup of course than the GX but just an example where even mechanical systems can be affected.

 

... perfectly safe until an emergency maneuver. Cost of a new tire vs. insurance deductible ... your choice ... and that's assuming no one gets hurt or even worse.

At least put your mismatched pair on the front.

 

cheapest and easiest to shave the one.
if replacing 2, put the new ones on the back. with the software, might not be as big of an issue, but still is safer.