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[blitzftw]

Hi,

Just wanted to get some opinions on the tires.


I purchased a 2011 328 xDrive CPO w/40k miles about 2 weeks ago. The dealer changed the front 2 tires during the CPO process. However, the rear tires are still the original tires-- dealer said they were not changed since they have ~4mm tread left.

Current Tires: 225/45/R17 Continental SSRs.

I saw in the service records that a wheel alignment was done when the 2 new tires were put on front.

The ride is bumpy and the car sort of shakes a bit when driving through older uneven roads. I figured this was just how the car drives due to the suspension and run-flats. However, a friend of mine just bought a 2011 328 xdrive w/30k miles. His came with 4-new tires (same tires as mine). When I drove his car, the ride was noticeably softer and more comfortable.

Is it a suspension problem with mine or the tires?



Thanks guys.

[chmsalman]

Your dealer is definitely not the smartest if he only replaced two tires on an x-drive. Its an all wheel drive car, your tread on ALL 4 TIRES must be within 2 32nd's of each other. The car constantly adjusts itself to give it perfect traction to all 4 individual wheels (the point of x-drive), with different tires front vs. back, you'll trip your car out and your gearbox will definitely be shot soon enough.

Go back to your dealer and make sure you have a set of 4 tires with almost exactly equal tread. The only way you could pull off different tires front vs. back is on a 2x4 car where the car isn't CONSTANTLY working to stabilize your ride based on information from all FOUR wheels.

I only know this because I was shopping for winters this season for my 2011 328xi and guys at a shop wouldn't sell me 2 used tires since I couldn't find a set of 4 tires since the car is AWD. Eventually after much looking I found a good pair of 4 that fit. A couple weeks later one of the tires had a buldge and had to be replaced. Guys went through a lot of trouble to find the same tire, same size, and almost exactly same tread. Didn't have to pay for anything since it was a warranty repair. If they couldn't find a tire within 2 32nd's of the other 3, they were ready to give me a new set of 4. All because it was AWD.

Another buddy drives a mustang, they let him buy just 2 winters for the rear.

Hope that helps. I feel horrible that a dealer would screw such a nice ride just to save cost of 2 tires. Pathetic.

[thegrinchboy]

RFT = Rougher, bumpier ride.

The advice you're looking for was already given to you within the first reply of this thread. Either go back to the dealership and b!tch about it, or suck it up and buy 2 new (or even 4 new) tires of your choosing.

[Delta0311]

Originally Posted by chmsalman

Your dealer is definitely not the smartest if he only replaced two tires on an x-drive. Its an all wheel drive car, your tread on ALL 4 TIRES must be within 2 32nd's of each other. The car constantly adjusts itself to give it perfect traction to all 4 individual wheels (the point of x-drive), with different tires front vs. back, you'll trip your car out and your gearbox will definitely be shot soon enough.

Go back to your dealer and make sure you have a set of 4 tires with almost exactly equal tread. The only way you could pull off different tires front vs. back is on a 2x4 car where the car isn't CONSTANTLY working to stabilize your ride based on information from all FOUR wheels.

I only know this because I was shopping for winters this season for my 2011 328xi and guys at a shop wouldn't sell me 2 used tires since I couldn't find a set of 4 tires since the car is AWD. Eventually after much looking I found a good pair of 4 that fit. A couple weeks later one of the tires had a buldge and had to be replaced. Guys went through a lot of trouble to find the same tire, same size, and almost exactly same tread. Didn't have to pay for anything since it was a warranty repair. If they couldn't find a tire within 2 32nd's of the other 3, they were ready to give me a new set of 4. All because it was AWD.

Another buddy drives a mustang, they let him buy just 2 winters for the rear.

Hope that helps. I feel horrible that a dealer would screw such a nice ride just to save cost of 2 tires. Pathetic.

Actually you can run a staggered setup without a problem on a X-drive car. You are right about the tread depth but the actual tire size does not matter as long as it matches the staggered setup specified in the owners manual.
In short, tread depth must match but a staggered setup is ok.

[blitzftw]

took 2 trips and a bunch of supporting documents, but dealer agreed that a mistake was made.

replaced the rear tires as well. ride is excellent now

thanks for all the help.