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New rear rubber for 2007


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When I bought the car last fall and had it inspected I was told that I had 4 years of rubber on the front, but only 1 on the back. Well, it seems that a year passes quickly. I really need some new rubber on the back. I have done lots of research both here and on consumer reports. Right now I am getting a lot of road noise and I believe that some of that is coming from the worn tires. I would like something quieter with a better ride. My car is my daily driver so I need a tire that will stand up and not need replacing after 5,000 miles.

 

Right now I am honed in on the Michelin Pilot Sport (101Y) BSW in the stock size of 285/40/18. Also the Continental Extreme Contact and the Yokohama Advan Sport.

 

Any thoughts before I pull the trigger???

 

Thanks,

 

Gregg

Edited by 68flashback
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Just don't get the Nitto 555 Extreme ZRs Rough ride and they do not handle well...especially in wet conditions!

 

I am about to try the Conti DW's and throw the Nittos away even though they only have 3K miles on them.

 

MSB Mustang - Mark

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I run the Michelin Pilot Sport PS2 in a 275/40-18 (all around)- LOVE em - have 8,500 miles on them which include 5 track days and they still have PLENTY of tread left - also great handling along with a SMOOTH / QUIET ride. Also have them on my 2009 GT convertible (which has 17,000 miles)with lots of tread left. The Continential Extreme Contact DW's work well and so does the Hankook Ventus V12evo K110 along with the Bridgestone Potenza RE760 Sport.

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OK, so I'm down to this:

 

Michelin Pilot Sport PS2's in stock size - most expensive

Michelin Pilot Super Sports in 265/40/18 - $90 per tire less

Michelin Pilot Sports in stock size - $55 per tire less

 

The Super Sports are the highest rated tire, and come on all the new supercars. Trouble is no stock size. Not even slightly wider. Is 3/4" narrower going to be an issue? I'm not going to the track in this.

 

What to do???

Edited by 68flashback
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pilot super spt is the latest tech,

 

the tire is oem on many hi end cars which go fast. much better than the pilot sport2

 

look at tire specs pdf sheet for pilot supersport from michelin. you can compare all sizes' specs, weights etc.

 

then look at tire width spec .

 

then you'll see the 18" size--- the 265 or 275 provide the widest footprint i remember.

 

i have 265-35-18's on my dd cobalt ss-T/C & the mechanical grip is quite superb- truly no drama!

 

///uber safe.

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OK so after more research and vanos' reply above, I am stuck on getting Super Sports. Now, what size?

 

I can get the 265/40/18's I mention above, but I also found that I can get 285/35/18's as well. Now what do I do??? Either way I will have to adjust my tune to fix the speedo I believe.

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Just saw this tread for the first time. I changed my OEM Goodyears on my '07 for Continental Extreme Contact DW, in stock sizes. Can't compare them to the Michelins but I'm very satisfied so far and the price is reasonable. Very smooth and quiet and very good in the rain.

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When I bought the car last fall and had it inspected I was told that I had 4 years of rubber on the front, but only 1 on the back. Well, it seems that a year passes quickly. I really need some new rubber on the back. I have done lots of research both here and on consumer reports. Right now I am getting a lot of road noise and I believe that some of that is coming from the worn tires. I would like something quieter with a better ride. My car is my daily driver so I need a tire that will stand up and not need replacing after 5,000 miles.

 

Right now I am honed in on the Michelin Pilot Sport (101Y) BSW in the stock size of 285/40/18. Also the Continental Extreme Contact and the Yokohama Advan Sport.

 

Any thoughts before I pull the trigger???

 

Thanks,

 

Gregg

 

 

Are you sure that Michelin produces 285/40/18? I'm sure they discontinued that size late last year. I just did a search of their website and cannot find that tire anywhere.

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Shipwright - not in Super Sports but they do in the Sports.

 

I'm so freaking confused right now I have no idea what to do. Maybe I should put on the black SVT rims with the Hoosier slicks that I have??? That would be fun for daily driver use!!!

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Shipwright - not in Super Sports but they do in the Sports.

 

I'm so freaking confused right now I have no idea what to do. Maybe I should put on the black SVT rims with the Hoosier slicks that I have??? That would be fun for daily driver use!!!

 

 

Unfortunately you are mistaken. Michelin no longer make ANY tire in 285/40/18. Pilot Sport tires are down to two sizes, 275/35/18 and 345/30/19. The 285/40/18 was discontinued late last year. Furthermore, if you use Michelins tire size locator you will draw a bland same for theyr vehicle function 2007 to 2009 GT500.

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Like I said before I run a 275/40-18 Michelin Pilot Sport PS2 on the stock 18x9-1/2 wheel all around and I also have a full size spare (same wheel and tire) in the trunk. Mine is a 2007 GT500 and yes it is lowered - by the way the Michelin's are on sale right now on Tire Rack.com ( Save $70.00 on a set of 4 ). It's nice to have a full size spare that matches because if I do get a flat on the road at least I know that it will clear the front factory Brembo brakes. The diameter is close enough not to have to worry about the speedo and it doesn't matter if it is a front or rear flat - they are all the same size - same wheel. Doesn't cause any issues with the TCS or ABS systems either.

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Like I said before I run a 275/40-18 Michelin Pilot Sport PS2 on the stock 18x9-1/2 wheel all around and I also have a full size spare (same wheel and tire) in the trunk. Mine is a 2007 GT500 and yes it is lowered - by the way the Michelin's are on sale right now on Tire Rack.com ( Save $70.00 on a set of 4 ). It's nice to have a full size spare that matches because if I do get a flat on the road at least I know that it will clear the front factory Brembo brakes. The diameter is close enough not to have to worry about the speedo and it doesn't matter if it is a front or rear flat - they are all the same size - same wheel. Doesn't cause any issues with the TCS or ABS systems either.

 

 

 

AHH! 275 That's a different story. I loved my Pilot Sports, Great tire. I to plan on putting PS2 (275/40/18) on the front and Proxes TQ's (315/35/18) on widened (11 inches) stock wheels early next year.

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I ran the 285-40-18's Nitto's in the front for over 6 weeks with no problems. So they can be run on all four...that is if we can still get them! Albino I'll bet the 275/40-18's all around feel great! Do you feel any difference on launch with the 275's? I'll bet not!

I did switch my Nitto's back to normal last week (255 front 285 rear with new McGard lug nuts) and the rough ride did go back to the front with the Nitto 555 Extremes. I really liked the feel of extra control with the 285's in the front but of course the 255's in the rear could not hook up at all! BUT since my clutch is gone again (45k miles after the TSB) it really does not matter because if I get on it at all it slips. (New McLeod RXT clutch goes in later this week.) NOTE: I discovered that if I run the Nitto's at 30psi I can just barely stand them! 6K miles on them so far at 2K per month.

This begs another question from the group. If I bought a new pair of Continental Extreme DW 285-40-18's and put them in the rear and then put the Nitto 285's back on the front would that be "bad/unsafe" to mix the two brands of tires? That would save $400-$500 or so? Then I could use one of the 255's as a spare...after buying another wheel! (Which would allow me to replace my one dinged up ugly wheel.)

It would also be nice to be able to run the 295-35-18's Conti's in the rear but they will not fit on our standard 10" rims.

 

A coworker has a 2012 Z06 with 335's on the rears! (335/25-20) Man are they impressive! I wonder how rough they would ride though being 20" rims? Maybe the active suspension on the Vet saves him from being beat up?

MSB Mustang / Mark

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Mark,

The stock wheel size on the 2007-2009 GT500 is a 18x9-1/2" all around . The stock tire size is 255/45-18 on the front and a 285/40-18 on the rear in which both the front and rear are 27.0 inches in diameter. The 255's have a sectional width of 10.0" and the 285's have a sectional width of 11.2". The recommended range of rim width for a 255/45 is 8.0" - 9.5" and the recommended rim width for a 285/40 is 9.5" - 11.0". If you look at this you will notice that the front tires are narrow for the rim width (sidewalls tilt inwards at the tread) and the rear tires are wide for the rim width (sidewalls tilt outward at the tread ) placing them at opposite ends of the range for wheel to tire fitment.This is done basically for 2 reasons - one for looks and the other is to promote/induce understeer which is required by US law ( thus validating an air bag as a safety requirement) for auto manufacturers. Neither gets you a maximum tire contact patch . What you might come across on the rears is the tires wearing out in the center of the tread area - this is not like in the old days (78 series tires) where wearing out the center meant that you were over inflated - it can be the exact opposite of being under inflated because of the combination of shorter/stiffer sidewalls and wider tread area. If you have ever seen a picture of a drag car (which uses LOW tire pressures) you will see that the center of the tire will grow outward (this is enhanced by having too wide of a tire on a rim) making the contact patch narrow and wearing out the center of the tread area. Now let me lay down something that will really interest you -A 285/40-18 tire with a load index of 96 (1565 lbs.) placed at 35psi will meet the standard load at 1565 lbs. each . At 32psi the load will be reduced down to 1510 lbs., at 29psi it will be 1444 lbs. and at 26psi the load will be only 1367 lbs. Multiply this by 2 because you have 2 rear wheels - so if you take the back half weight of your car and apply it to the load capabilities of the 2 rear tires you will start to understand why there is a recommended tire pressure on the door jamb and why the vehicle has a minimum required speed and LOAD index. On a 275/40-18 tire the wheel width range is from 9.0" - 11.0" so ideally one would want to run either a 9.5" or 10.0" rim width to be right in the middle of the range placing the sidewalls parallel and maximizing the width of the tire contact patch if/when you have the proper tire pressure for the vehicle weight based upon the load index. The diameter of a 275/40-18 is 26.7" ( vs the 27.0" stock ) so you will need to check the number of Revolutions Per Mile as compared to the stock sizes to find out the percentage of change which will effect the speedometer. The rear end gear ratio is not going to be changed by a different diameter tire but the distance traveled per rotation will.The sectional width of the 275/40 is 10.8" which is ideal for the rim width of 9.5" ( rule of thumb is tire sectional width 1" wider than the rim/bead width) DO NOT DROP TIRE PRESSURES in order to fix ride quality issues unless you have checked and know that it can maintain the load requirements. Remember that the load in the rear increases when you "launch" / aka weight shifts from the front to the rear as the vehicle wants to go forward which means you have increased the load from just sitting parked. Before this gets into me writing a book on tires - DO NOT MIX DIFFERENT TYPES AND /OR BRANDS OF TIRES ON THE STREET BETWEEN THE FRONT AND REAR !!! It is not just an issue with handling ( understeer/oversteer ) or tire life BUT, it is with the charater differences that occur under BRAKING that can be the worst problem that gets created . The TCS and ABS no likey - oh they will still work but the system won't work at its optimum level. Enough said for now sorry all for putting such a long post but it seems like some info to share with the community.

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  • 3 weeks later...

Albino,

 

What an outstanding post! Thanks for the lesson on tire sizes and pressure. I am back to the standard 255's in the front and 285's on the rear with the Nittos. I am running them a bit low however. At 31 psi cold on all four it makes my 90 mile round trip every day tolerable. When they hit 35k miles in a year or two then I will will go with the Conti DW's.

 

Thanks again for the great post!

 

Best Regards,

 

Mark / MSB Mustang

 

PS - My Nitto Extremes do not seem as bad now that I have a new McLeod RXT Clutch that is not slipping... like my "second" Ford clutch was.

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  • 1 year later...

I would like to have MPSS, since everyone seems to like them. I am still running the stock 18" 9.5" wide wheels on my 08.

So it seems that 285 is the widest tire for the 9.5" wide wheels.

So my thought is to go with stock widths with less aspect ratio. Thinking of 255/40/18 front and 285/35/18 rear.

These are about 1" smaller in diameter.

 

Two questions:

Do you think they would look OK?

And would I need a reflash for the size adjustment?

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