Utopia Texas

Had my older, worn out Perelli tires replaced with Michelin Pilot AS/3 's yesterday and checked the pressure this morning and found the installer was 10 pounds higher in each tire than the door sticker. When changing brand of tires, but still at the original size, do you still use the door sticker for pressure numbers or are the numbers different for different brands? Thanks...

Heatwave

I dunno. But here's what I did in the same situation as yours: I used the MB door sticker pressure settings. My tires are Michelin Pilot AS/3 also. The door sticker pressures work for me.

Ron Martin

This subject has been bantered around a LOT ! One of the basic rules of thumb is add 3PSI to the cars suggested sticker and then drive the car to test your own personal liking.


For years I have kept higher pressure in my tires than other folks and liked the more firm ride- together with leaving the ABC in "sport" mode.


Lower pressure will indeed yield a nice soft Mercedes sedan ride, but will create more wear on the edges whereas the harder setting wil wear the tires centers more ... It all depends on the drivers preference..


In both our cars (with 18" rims) I keep 38F and 40R and adjust per static outside temperature ...




Ron

Leester

Ditto...
Cheers.

retcav1sg

OP and others...how do you like the Michelin A/S 3 versus the Pirellis. Any flat spot issues with the Michelins? Ride comparison?

Utopia Texas

It would be hard for me to compare the Pirellis to the Michelin since the Pirellis were 6 years old, quite worn and I haven't put many miles on the Michelins yet on different pavements. Newer tires are more flexible than older tires also. So far the Michelins are quieter than the Pirellis and grip a lot better on local road curves I have driven a lot over the years. I am very happy with them at this time.
PS- I have two older cars, one that is 97 years old and the other 85 years old and both have tires that are over 30 years old. The tires are rock hard and ride pretty rough.
1919 Ford Model T...1931 Ford Model A

mrwhattie

The first thing one needs to do is get your own good tyre pressure gauge, don't rely on the pressure gauge at the garage, they are never accurate. What I always do is keep a close eye on the wear on the edges and center, you will soon know what pressure your car needs, from my experience most tyres/sizes need minimum 2.2bar

DonMarco

I've had many sets of Pirelli tires on my previous Porsche 911's and Cayenne. Great performance, noisy as heck. Never again. Michelin for me.

dRockSL55

I haven't used pirellis on my SL, however a friend of mine purchased an SL55 just a few months ago with pirellis mounted (though I'm not sure which Pirelli model) Though her tires had great tread, a sidewall bulge appeared on one (pothole) so she opted to just replace the entire set. Following my strong recommendation from personal experience, she went with the Michelin a/s3s. The difference is night and day, she says cornering response and driving confidence is dramatically better. The michelins have better dry traction and extremely better wet traction. The ride is much softer, smoother and quiet! She is very pleased.

On my own car I never experienced flat spots with the a/s3s even after sitting for several weeks. I currently have pilot sport ps2s and they do get minor flat spots after about 4-5 days. I will be switching back to a/s3s with the next tire change.

retcav1sg

Drock...Thanks, that's the kind of feedback I was looking for. I've had the A/S 3s on a C6 corvette in the past and they were awesome. The pirellis I have were on the car when I bought it and are almost new but ride like crap and flat spot over night. Hate to replace new tires but I'm afraid I'm missing out on the true SL550 experience with the POS pirellis

Thanks again

anothercar

I have the A/S 3's and run them @ recommended PSI inside the door.

Quadrobenz

On my 2005 SL600 I found 36 front 32 rear to be the best pressures to give even wear across the tire, crisp steering and almost neutral handling. With the lighter 550 the front pressure would likely need to be a little lower. The brand of tire should not be a factor. I find that when my cars are returned from the dealer the tire pressures are almost random. When my wife's E63S was returned from service last week the left front tire was 38psi and the RF was 42psi. When it went in the tires were each 51psi per the door sticker for 186mph use. Do not trust the dealer to set the pressures correctly. I always check them cold after sitting overnight and then correctly set the pressures.