Different tire size.

Not sure on the same size since it came from factory like that, But the rear end of the car may need alignment..

Is your car AWD? If so you need the same size tire front and back. I checked the owners manual and you need the same size tires front and back. The dealer was an idiot if they gave you two different sized tires.

To get the best mileage out of your tires you need to rotate them side to side and front to back which is recommended in the owners manual. You can only do this when the tires are all the same size.

From the owners manual ----- Mixing tires could cause you to lose control while driving. If you mix tires of different sizes, brands or types (radial and bias-belted tires), the vehicle may not handle properly, and you could have a crash. Using tires of different sizes, brands or types may also cause damage to your vehicle. Be sure to use the same size, brand, and type tires on all wheels. Your vehicle may have a different size spare than the road tires (those originally installed on your vehicle). When new, your vehicle included a spare tire and wheel assembly with a similar overall diameter as your vehicle’s road tires and wheels, so it is all right to drive on it. Because this spare was developed for use on your vehicle, it will not affect vehicle handling.

It is AWD and those tires came on the car from the factory . There is even a sticker on the door stating the two different tire sizes . I had the alignment checked and it is fine .

If you say so..................

Many of the CTS models have different size front vs rear. The wear that you experienced is definitely NOT normal. You should contact the Michelin representative in your area. I'm confident that they will stand behind their warranty and not require you to replace the still good front tires. To top it off, if you buy directional tires, you can't put them on the opposite side, so then there's no possibility of rotation (as on my 1998 BMW Z3). I have had some interesting mixed results regarding wear with Michelins. They are the best tires on the market, but when I bought tires from a particular store, I got less than half the miles that I did on the previous set. Call your Michelin rep, or even go to the Michelin website and contact them to see about the warranty.

I just bought a 2009 SRX and had to have the front tires replaced. The sticker on the side of the door said it takes 255/60/R18s on front and 235/55/R18s on the rear. This is what it comes with from the factory. Yes, I realize these CANNOT be rotated like this. As for the "must all be the same size for AWD", that all depends. The reason for this is so that the front and rear shafts are turning at the same speed when going straight. However, it the manufacturer changed the gearing in the front differential to compensate for the different sized tires then the drive shafts will be turning at the same speed with the factory tires. I'm guessing that lots of people second guess the manufacturer and put the same size tires on the front/rear, and if the differential gearing is set up for the different sized tires (as I suspect it is), then it would explain why people have issues with the transfer case chain or the rear differential.

Good answer Mayhem8...

Actually 235/65R17 are the same dia. as 255/60R17. they are both 29" dia. the 255's are just wider for the back of the vehicle, so it would be ok to have the same size tires all around.

Can I have 255 60 r17 all around on a 2008 Cadillac srx rwd

Yes you can... Because only one difference available between in two different tire sizes is width... All the other parameters are same on 235 65 17 and 255 60 17 tires...

You probably wouldn't notice any initial difference in handling from having all tires the same size, but it may not steer as good in the snow because, by design, the fronts should be turning slightly faster than the rears. Just my personal opinion, but the wider all-season tires that you see on these vehicles already make the handling kind of suck in the snow. A narrower tire gets more "bite" because it has less of a foot print to spread the vehicles weight over, meaning you get more lbs/sq in pushing down on the road with a narrower tire. Part of that opinion is based on my wife sliding off the road at a slow speed in a relatively small amount of snow because the vehicle would not turn. This was with brand new front tires of the manufacturers suggested size too. Just my $0.02. YMMV.

FWIW - I'm also Mayhem8

I have a question abt tires my escalade is awd all my tires are the same size just one is wider than the others will this fuck up my differential or would it still be ok?

Wow, i stumbled upon this website after I punched in a tire size and the word Michelin; looking for prices. Most of these answers are wrong and stated like the person actually knows what they are talking about. Staggered fit tires aren't a big deal and are pretty common. No, you cannot rotate staggered fit tires unless you rotate them laterally. Yes all-wheel drive and/or 4 wheel drive vehicles with staggered fit tires happens. No "if you say so" necessary. Among vehicle mechanics this is common knowledge. I have told many a young buck starting out in this business that Googling a code, symptom, torque spec, wiring color chart/schematic and/or troubleshooting tip should be done with Extreme Caution. It is a huge disservice to say things like "they definitely do not have different size tires on all wheel drive vehicles" to someone on the side of the road in the rain at 2 in the morning or a young single mother at a chain vehicle tune-up shop that pays their techs minimum wage. I just talked to a young guy who is just starting to move up from a beginner Tech have to buy a head for a 2008 Honda because the torque spec they came up with was 29 foot pounds. I asked him how he diagnosed the head gasket itself... It was because "the customercould smell burning coolant." The 101 basic questions that go along with smelling burnt coolant could not be answered (from his shop to me) ie; coolant consumption, pressure in the surge tank or radiator; How did the heat work? Was it overheating on the gauge? Are you sure that you smelled burning coolant too? The real diagnostic questions could not be answered either, oh you know the ones where you have to open the hood and handle a wrench; like if you pump a little air into the spark plug hole with the valves closed can you hear it coming out anywhere? like the intake, the end of the tailpipe; bubbles in the radiator with the cap off? If you get all fancy and hook a pressure gauge up to that spark plug hole and stop putting air in to it what happens? Does the air seem to leak out? Pretty fast? Anyways this is a new generation of techs that look to the internet for answers... everybody should use Extreme Caution when posting or getting an answer. I am a career mechanic and allegedly a super duper one. Super duper with the pressure gauge and super duper with watching the data. I say that to say this; After a long day of smashing my knuckles I hardly feel like going home and getting on the computer and telling people how to do something I just spent seven hours trying to figure out. Just to be wedged in between two ridiculously wrong answers; all three to be taken with the same size grain of salt. As a matter of fact I don't have a computer at home, I am writing this on my cellular device. But, anyways if anyone knows the best price shipped to Boston Michelin LTX at/2's 255/70r18. M+S let me know. And P.S. 2 tires can have different numbers but have the same height / outside diameter. And P.P.S if one of your tires is 11 PSI lower than the rest does your differential or transfer case or transaxle eat itself up? Negative

As far as I can tell, Escalades used the same size tires. You can verify this in your owners manual or on the sticker on the side of the driver's side door. FWIW - If I Google the diameter of the tire sizes mentioned for the SRX, the fronts are slightly taller than the rears. Years ago while helping a friend rebuild a Chevy 4x4 front end we found that the crown gear was 1 tooth different between the front and rear end. The explanation I found at the time is that in slippery conditions you want the steering tires turning slightly faster than the rears for better steering. I suspect that Cadillac achieved this in some vehicles with tires rather than gears because I can think of no other reason for different diameter tires between the front and back. BTW - AWD vehicles generally have a center differential, which the older 4wd's did not. This is one reason you weren't supposed to engage 4WD on bare dry roads because there was no way to compensate for the difference in the front and rear axle speeds, especially while turning. Anyone that's experienced four wheel lock-up knows exactly what I mean.

Can install 275/65 18 2006 srx cadllic all whell drive

Bridgestone DUELER H/L ALENZA PLUS 80K tires. I have over 267,000 miles on my 2008 srx tires bought 2014 over 100,000 miles on them. The fronts are $179 ea and the correct size rears are $220. So for the extra $80 for the correct sizes makes sense to me.