Changing Tyres and Brake Squeal

[SteveB730]

Hey all, MyAlloys.co.uk are changing all 4 of my tyres later this week, moving from Bridgestone RFTs 20 to Michelin Pilot Sport 4S, looking forward to the ride improvement and handling! I think I made this up and sorry for the dumb question but when they take off the wheels, is there anything special that needs to happen because of the air suspension or anything they should be doing differently?

I then plan to get front/rear wheels laser aligned via. Hunter System, around £80 which I don't think is too bad with full report before and after. Any specific advice on this relating to the suspension or anything? They should know what they are doing but usually my luck I get someone new or incompetent so just for my paranoid peace of mind, lol

Finally I have some brake squeal and hoping it's just a small stone or debris, I know my pads are fine on the wear, but it happens once the car has been driving about 10 minutes and only squeaks (high pitched) loudly when coming to a stop at around 5mph. There is probably no chance of finding it having a look under the car, around the brakes etc so I guess I will get them to have a quick look when replacing all 4 wheels on my car.

Thanks for any guidance.

[Markr]

Interested what you think of road noise levels with the Pilot’s vs Bridgestone, as my experience in Audi A8L with Pilot’s was a drastic increase in Road/tyre noise vs prior Goodyear’s - could not wait to get back!

[SteveB730]

Interestingly the Michelins are 71DB at the rear with the Bridgestones being 73DB but I'll let ya know all the differences once I have them fitted including external noise.

[13M5F10]

Originally Posted by SteveB730

Hey all, MyAlloys.co.uk are changing all 4 of my tyres later this week, moving from Bridgestone RFTs 20 to Michelin Pilot Sport 4S, looking forward to the ride improvement and handling! I think I made this up and sorry for the dumb question but when they take off the wheels, is there anything special that needs to happen because of the air suspension or anything they should be doing differently?

I then plan to get front/rear wheels laser aligned via. Hunter System, around £80 which I don't think is too bad with full report before and after. Any specific advice on this relating to the suspension or anything? They should know what they are doing but usually my luck I get someone new or incompetent so just for my paranoid peace of mind, lol

Finally I have some brake squeal and hoping it's just a small stone or debris, I know my pads are fine on the wear, but it happens once the car has been driving about 10 minutes and only squeaks (high pitched) loudly when coming to a stop at around 5mph. There is probably no chance of finding it having a look under the car, around the brakes etc so I guess I will get them to have a quick look when replacing all 4 wheels on my car.

Thanks for any guidance.

Nothing different to do. I just swapped my wheels out the other day. Pretty simple job.

As for the break squeal, I bet it's debris. Have them clean it up. Maybe take it to a car wash and pressure wash it too. Shouldn't be squealing.

I went from the Pirelli RFTs to Michelin PS4S and it's a night and day difference in ride quality, comfort, and noise reduction.

[SteveB730]

Had my tyres fitted this morning, he blew out a tonne of brake dust on all wheels and some lumps of dust so hoping that has sorted it now, no squeaks yet. I'm a light braker and good at predicting ahead (engine braking) so the brakes don't get used very much or that hard, might be why I had so much buildup.

Will report back on Michelin's after I have run them in.

On a side note they inflated to 36 psi all round, but when I go to Michelin's website it has this (see photo), saying 32 PSI recommended?

I would go via the door card for the pressures but I'm thinking those pressures will be designed for RFT tyres and maybe that is different for the PS4s! I usually only have a light load so need the smaller values, anyone running 32 all round? Cheers/

[13M5F10]

Originally Posted by SteveB730

Had my tyres fitted this morning, he blew out a tonne of brake dust on all wheels and some lumps of dust so hoping that has sorted it now, no squeaks yet. I'm a light braker and good at predicting ahead (engine braking) so the brakes don't get used very much or that hard, might be why I had so much buildup.

Will report back on Michelin's after I have run them in.

On a side note they inflated to 36 psi all round, but when I go to Michelin's website it has this (see photo), saying 32 PSI recommended?

I would go via the door card for the pressures but I'm thinking those pressures will be designed for RFT tyres and maybe that is different for the PS4s! I usually only have a light load so need the smaller values, anyone running 32 all round? Cheers/

I run 32 cold and in Texas heat it gets up to 34-36. Runs great.

[SteveB730]

Thanks mate, seems like you have it spot on. I just got this from Michelin via email after contacting them, based on my 730D M Sport 2016 with Pilot Sport 4S.

Front 245/40/ZR20 99Y: 31 PSI
Rear 275/35/ZR20 102 Y 31 PSI.

With full load: 34 PSI front and 37 PSI rear.

[Aussie_7er]

Hi, would you be able to take some photos and share with the forum?

I’m looking to swap out my RF Pirellis to non-RF PS4s, but I did this on my Mercedes and they always look flat. They are the same size tyres as stock, but the non-RF tyres buldge out the side of the wheel. I put almost the maximum tyre pressure in, and they still look a little flat. Really annoys me.

[13M5F10]

Originally Posted by Aussie_7er

Hi, would you be able to take some photos and share with the forum?

I’m looking to swap out my RF Pirellis to non-RF PS4s, but I did this on my Mercedes and they always look flat. They are the same size tyres as stock, but the non-RF tyres buldge out the side of the wheel. I put almost the maximum tyre pressure in, and they still look a little flat. Really annoys me.

Here are some pics of the PS4S in my stock 648Ms and my new wheels.

Michelin is known to have rim protection where it flairs out. I do think Michelin tires look best. They seem to have a better profile than most tires in the market.

These are both stock sizes. 245 F and 275 R.

[SteveB730]

Originally Posted by Markr

Interested what you think of road noise levels with the Pilot’s vs Bridgestone, as my experience in Audi A8L with Pilot’s was a drastic increase in Road/tyre noise vs prior Goodyear’s - could not wait to get back!

Ok so I've done a good 500 miles now on my new MP4S tyres and of course the ride is far softer and supple than the run flats, glide over uneven surfaces/holes, the grip in the wet feels a lot more planted too but of course with 7mm on the tyres they are going to feel that way.

They certainly aren't quiet by any means and the 7 series pre LCI was criticised for not having as good sound proofing as rivals or even previous 7 Series models, having said that to me they sound quieter than the Bridgestones.

I'm glad I switched from the awful run flats!! Ok if you are a chauffeur and have to get to that airport at all costs but I don't and comfort is what I want!