NEED ADVICE ON TIRES REPLACEMENT QUICK.

[jspdr]

Originally Posted by jeremym

I've read that with BMW awd systems, it's not a good idea to mix/match different tread depth tires. It could be a conspiracy, but it makes sense to me. As JCL mentioned, it could affect the transfer case.

Me too, i agree. I read it from Car and Driver and Tire rack articles. I think i'll go with one new shaved to the same tread depth. But, i am still waiting from BMW technical support.

[jeremym]

Originally Posted by sarends

These are OEM BMW sizes

Perhaps you don't understand what I'm saying. There have been reports that even a 1/8 inch of tread difference between tires causes the transfer case and/or differentials to wear prematurely due to the wheels rotating at slightly different speeds.

[jspdr]

Today they call and tell me that according to BMW technical support it is ok to have one new tire replace without any affect to the AWD system (transfer case). I cited articles from Car and Driver and Tire rack say otherwise. They insist to replace new tire, no shaving. I said to them i only agree to if they have confirmation document from BMW's, otherwise, i need them to do the tire shaving. Waiting for final decision.

[ard]

You cannot "repair" the damaged rim to 'factory' standards unless you refinish the entire rim.

The $150 repair is NOT the same as an undamaged wheel.

Dealer must be thanking his lucky stars you dont know that!

Make them replace the rim.

[ard]

Originally Posted by jeremym

Perhaps you don't understand what I'm saying. There have been reports that even a 1/8 inch of tread difference between tires causes the transfer case and/or differentials to wear prematurely due to the wheels rotating at slightly different speeds.

This is internet rumor.

You need much more difference than a worn tire will give you...

[ard]

Originally Posted by jspdr

Today they call and tell me that according to BMW technical support it is ok to have one new tire replace without any affect to the AWD system (transfer case). I cited articles from Car and Driver and Tire rack say otherwise. They insist to replace new tire, no shaving. I said to them i only agree to if they have confirmation document from BMW's, otherwise, i need them to do the tire shaving. Waiting for final decision.

Car and driver and tirerack are in this to sell tires...

Do the math yourself..... i wrote this up somewhere, but the 'mis-match' in rotational speed is actually small.

My wife's friend once bought 4 new tires when the tire store convinced her that 'replacing only that one tire' would damage her MDXs AWD system. Tires were over 60%.

A

[Gregory891]

Rims are one issue, I won't comment on that.

Tires.

1) For any car, same type (brand & model) and size of tire on the same axle

2) Balance of wear (used on one wheel and new on the other) is a safety, handling and (potentially) alignment issue. Take the good tire from that axle and use as your spare tire. Then put a pair of new tires on that axle (rim with bad tire and your current spare tire rim). Remember, tires age - so having a less old spare tire might save you some day

3) When you but ONLY a pair of new tires, ALWAYS put them on the rear axle - regardless of RWD, FWD or 4WD. Some people believe it's up front, which is 100% wrong and VERY unsafe.

There is an excellent skid pan video on the Michelin USA web site to show you WHY.

4) For a 4WD vehicle, European (and good practice) safety and TUV requires the same type (brand and model) tire on the front & rear of the car.


Best regards

[ard]

Originally Posted by Gregory891

2) Balance of wear (used on one wheel and new on the other) is a safety, handling and (potentially) alignment issue. Take the good tire from that axle and use as your spare tire. Then put a pair of new tires on that axle (rim with bad tire and your current spare tire rim). Remember, tires age - so having a less old spare tire might save you some day

So I hit a piece of metal and destroy on tire... Needs to be replaced.

Existing tires at 60%.... Unsafe to replace just one?

How about 80%? Still unsafe?

90% unsafe?

98%. Unsafe?

While a brand new tire will need some miles to run in, my question is focussed on the 'unsafe' aspect of the not new tires in this equation...

A

Ps.
(Btw, three of my cars have no spares ... But I do store extra tires in the shop. )

[jspdr]

Originally Posted by ard

Car and driver and tirerack are in this to sell tires...

Do the math yourself..... i wrote this up somewhere, but the 'mis-match' in rotational speed is actually small.

My wife's friend once bought 4 new tires when the tire store convinced her that 'replacing only that one tire' would damage her MDXs AWD system. Tires were over 60%.

A

The dealer could not come up with any info from BMW NA to prove one way or the other. They won't do any shaving but, they agree to pay the total cost for all that from Tire rack. I just had the rim perfectly re polish, cost me $150, and i did not want to push it. I think i'll take the money and replacing both.

Gregory 891
Mine are staggered, so it's only goes on the front.

[Gregory891]

Good idea to replace both, which is what I was politely suggesting you do. One other element I neglected to add to the "tire talk" points is AGE of tires. It's rubber and it ages.

A pair of new tires is a good idea. If you the staggered (likely the 19") set-up, then keep the still good front tire for a spare or make a very nice tire swing out of it.

Remember that we & you drive an X5, not a Yugo or a Lada.

Remember that for ANY car, the three elements that have a significant impact on your safety are visibility, adhesion and braking.

Don't go cheap on wipers.
Don't wait on tires, your whole life is on a contact patch the size of a sheet or two of paper.
Make sure your brakes are good and flush fluid at least every two years (annual is even better).