ALL-WHEEL DRIVE TIRES

[Boatwrench]

Yesterday I was at a Big-O Tire getting front tires put on my daughters car. Told the tire shop manager sales guy I had just done the front pads and didn't like the fact the tires were bad. They were completely bald. While sitting there waiting for the job to be performed I over hear the guy tell a customer that the customer was lucky the puncture was wear it was, had it been in the last inch of tread by law the tire would need to be replaced and that would result with all four tires need replacing because the vehicle had all wheel drive. Huh? I left the car industry before all wheel drives (other than Jeep's BW1399 Quadra-Tracs) were popular, but this didn't seem correct to me.

Are all four tires required to be replaced at the same time on AWD vehicles?

When my daughters car was ready, tire sales guy tells me the brakes looked good, the tires wore out due to lack of rotation and she'll experience vibration because the rear tires would be cupped. Really? I asked him to show me the cupping on the rear and he couldn't. What a JO. I digress.

Are all four tires required to be replaced at the same time on AWD vehicles?

 

[kastein]

If you don't like wearing your spider/side gears and cross shaft out (no bearings, the gears ride directly on the shaft) prematurely, yeah, it's a good idea.

I can tell when one of my rear tires on the MJ is low on air because the spider gears make a racket on the cross shaft when the tires aren't spinning exactly the same speed on the highway. Of course, it's a d35 that was whipped for the last 200+ thousand miles and by the look of it I'm the first, or MAYBE the second, person to ever change the lube in it.

 

[Kyle Petterson]

It depends on the vehicle, but, usually yes. Think of it like having 2 different sized tires on a locked rear end.

Now, with the AWD, is it likely to cause any damage? Not from what I have heard, but is the possibility of getting sued for damage to someones drivetrain worth the profit from 1 tire? Probably not.

As far as your problem goes, typically lack of rotation will cause the front tires to wear out faster and the rears to cup. Run your hands across the tread on the rears and you'll probably feel it. Unless it's really severe, however, there's no reason to replace them.

 

[midnight]

I all depends on how much tread is left. If all 4 tires have really good tread, replace the one with the nail with a similar or identical tire. If both tires on the axle with the flat are worn, go ahead and replace both to eliminate spider gear wear and tear. But to replace all four because one is ruined.......that is ridiculous. Just stick with the same size and style (AT, Street, Mud, whatever) on all four corners. the difference in tread wear should have no ill effect on the vehicle. I changed tires for 6 years and never heard line of BS from any sales person.

 

[NW-ZJ-SCOTT]

Pfff BS... i have a 35 and a 31 on the front of my 5.9 and the rear has 2 different 33s. Drives like a dream! (nightmere)

 

[Tim_MN]

AWD, yes, you really need the 4 tires to be the same diameter. AWD's usually don't have a transfer case and they use one or more viscous couplers which don't tolerate abuse very well or very long.

True 4x4's with transfer cases usually don't have any viscous couplers, so the mechanical differentials and transfer case can handle the stress of slightly different size tires.

Stop going to fast food style, brand name franchise tires stores like Big-O, they are usually only staffed by sales people and tire changers. The local Tires Plus always wants to sell me 4 new tires, new wipers, a lifetime alignments and a new air filter. I only deal with the local independent tire store that services everything from ATV's to 18 wheeler big rigs. The tire techs have years and years of experience and will tell you truth about your tires, suspension, and alignment because they want your repeat business and recommendations.

 

[RCP Phx]

Thats not as bad as vehicles were all 4 tires are different and you have to buy say just a left front(they usually have to be ordered).

 

[Johnnie Walker]

Good rule of thumb for AWD and 4x4 in general is to have all the tires equal. I even know some shops that will only replace all 4 on AWD and 4x4 vehicles. It should really be the customer's choice, But all the tires should be the same.

 

[cwstnsko]

When the tire shops start giving me un-wanted extraneous advice like how many tires I need to buy or what size I am allowed to run, I start taking the wheels off the vehicle and take them in loose. This seems to cut them free from the advise of the corporate lawyers and they are free to do exactly what I ask for. The 1st time I had to do this was about 8 years ago at a Costco. I parked right in front of their shop, pulled out the highlift, and pulled the wheels off my YJ one at a time and rolled them up to the door. This was the only way the would install 33s for me. Les Schwab wouldn't even touch my YJ because of the Daystar polyurethane body mounts ... and Discount wanted $100 more than Costco for the same tires.....

After all that crap, I bought myself a HF tire machine which I've gotten quite good at using. (no more begging to get a flotation tire mounted on a 7" wheel, if that's my choice.) I'd love to find a balance machine for home so I could do everything myself.

 

[Kittrell]

I have an Audi, I'll echo what has been said. Yes, if I replace one, I replace them all.

 

[redriverhugh]

Our local Costco won,t mount 35's on my XJ because it's not original equipment due to lawyers and liability but they will also allow me to bring in the tires loose and then they will do it. So I said to heck with them and since they wanted $315 each for 5 I ordered on line from a 4 wheeler place and got my KM2's delivered to the US Can border for $210 each. As far as different tire diameters yes it,s pretty important to have the same size tires especially on an AWD machine. By rotating your tires at least you can evenly wear out all of them and not damage the driveline and get the most bang for your buck.