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Over the past few weeks I have been playing around with the tire pressure in my 2015 S550. I have the 20" sport wheels with Michelin AS4 tires. Not in love with the tires but that's a story for another day.
I've run the tires at 32psi, 35psi, and 39psi back-to-back to compare them.
Believe it or not, the car rides much better at 39psi. At 32psi and 35psi the car crashes over poor surfaces (bumps and potholes) and it feels about the same. At 39psi the "crashes" are noticeably less pronounced - the car glides over imperfections the way you would expect a Benz to. My commute is mostly city but I verified these same findings over a 600-mile all-highway roadtrip.
Does anyone else prefer keeping the tire pressure high?
Over the past few weeks I have been playing around with the tire pressure in my 2015 S550. I have the 20" sport wheels with Michelin AS4 tires. Not in love with the tires but that's a story for another day.
I've run the tires at 32psi, 35psi, and 39psi back-to-back to compare them.
Believe it or not, the car rides much better at 39psi. At 32psi and 35psi the car crashes over poor surfaces (bumps and potholes) and it feels about the same. At 39psi the "crashes" are noticeably less pronounced - the car glides over imperfections the way you would expect a Benz to. My commute is mostly city but I verified these same findings over a 600-mile all-highway roadtrip.
Does anyone else prefer keeping the tire pressure high?
I keep them at 38psi here at 5280 feet. Same car, same wheels, AS3s.
I have also noticed what you mean by crashes over the bumps if tire pressures are lower than usual or recommended values .That doesn't mean we have to overinflate them either . Well, I find it it between recommended minimum cold pressure and maximum cold pressure . If not ,I run the tire pressure what door or fuel sticker says in minimum level .Let's not forget as we drive the car the tires will also get hot which translates to increasing in pressure to what we adjust before taking off
I too have been playing around with tire pressures lately, also on 20” wheels, but Good Year RFs. I have found that about halfway between min and max pressure, from the fuel door, is working best for me. I live in GA and it took me a few days to get the right “cold” pressure, as it’s summer right now and there is no cold! As @BenzV12 said, once you start rolling the temperature and pressure goes up pretty quickly!
Right now I’m happy with what I have things set at, I’ll see what I need to do when it eventually cools down again
I too have been playing around with tire pressures lately, also on 20” wheels, but Good Year RFs. I have found that about halfway between min and max pressure, from the fuel door, is working best for me. I live in GA and it took me a few days to get the right “cold” pressure, as it’s summer right now and there is no cold! As @BenzV12 said, once you start rolling the temperature and pressure goes up pretty quickly!
Right now I’m happy with what I have things set at, I’ll see what I need to do when it eventually cools down again
Do it 1st thing in the AM before the sun hits the tires... Thats when it will be most even all around.
I’ve noticed my tire pressure raises about 4-5psi max when warmed. So my 39psi cold raises to about 43psi, but again, the ride is wonderful at that pressure.
All Cars Lost To Hurricane Isaac (W124 E420 revived - added 88 Allante 14 S550, 17 S63
I thought it was just me.....im 37 front - 39 rear on both my S550 and S63
It gives the smoothest and most forgiving ride... Although this is still somewhat harsh on the S63....
The S550 has Bridgestone quiet tracks and they are truly amazing at these pressures.. I don't hear or feel the road... A true S like experience
It goes over 40 psi on hottest days, and the ride is still excellent
It would seem logical that less air ( up to a point) would allow better absorption over bumps however I found this not to be true In my last several S classes... Of course this opinion is from the sensors in the seat of my pants... your own sensors may vary
Originally Posted by Mitch Alsup
I run my tires at 39 PS, too, and for much the same reasons.
The car feels sloppy when the tires are less than 38 PSI.
Last edited by kafklatsch; 07-30-2022 at 03:16 PM.
I thought it was just me.....im 37 front - 39 rear on both my S550 and S63
It would seem logical that less air ( up to a point) would allow better absorption over bumps however I found this not to be true In my last several S classes... Of course this opinion is from the sensors in the seat of my pants... your own sensors may vary
Perhaps the tires have effect as well as just the pressures. Run Flat vs Non Run Flat might be significant.
I’ve noticed my tire pressure raises about 4-5psi max when warmed. So my 39psi cold raises to about 43psi, but again, the ride is wonderful at that pressure.
My car has 19" wheels and I immediately played around with cold psi measurements soon after I bought it. I have a compressor at home, so over the course of two weeks I tried 32 - 39 and I found that the best cold psi for me is 34psi. The car handles well and the fuel economy is good. The psi rises 4-5 psi once the tires are warmed up, so the cold psi of 34 tends to be 38 or 39 once fully warm.
I thought it was just me.....im 37 front - 39 rear on both my S550 and S63
It gives the smoothest and most forgiving ride... Although this is still somewhat harsh on the S63....
The S550 has Bridgestone quiet tracks and they are truly amazing at these pressures.. I don't hear or feel the road... A true S like experience
It goes over 40 psi on hottest days, and the ride is still excellent
It would seem logical that less air ( up to a point) would allow better absorption over bumps however I found this not to be true In my last several S classes... Of course this opinion is from the sensors in the seat of my pants... your own sensors may vary
Interesting. Is that hwy or city? Ever measure your tire temp? Yours should ride cool at 37/39.
100F right now. In my area it rarely gets much hotter.
Here it will be +100 today. I’ll do a 20 mi trip at 75 and measure tire temp and psi. You got me wondering. Starting psi will be 31 all 4 Pirelli RF.
Update
cold temp on my tires is 94.5. Using a race gage, all 4 are at 32 flat. I’ll try to reset TPS on a slow early roll.
TPS would not reset to gage…2 different hand gages matched at 32. Street temp 165*. Air temp 99*
After 30mi at 75/80mph measured in a hot *** garage:
RF 133*/35psi
LF 136*/36psi
RR 127*/34psi
LR 130*/36psi
Street temp 165*
All measured with same gage
Temps are off sidewall. Center tread was +4*
Not married to the Perellis. Normally would be Mich or Bstone.
I’ll run this again but starting at 35psi with zero calibrated gages to make sure.
All Cars Lost To Hurricane Isaac (W124 E420 revived - added 88 Allante 14 S550, 17 S63
Originally Posted by Donnymac
Interesting. Is that hwy or city? Ever measure your tire temp? Yours should ride cool at 37/39.
Good question, i gets in the upper 90's and ill see 40/42 psi... i think the MB star tells the tire temp... but not sure...ill give this a shot to see what the temps are when i get a chance
I've done the same experiment with my 2019 S650 Maybach and in my opinion, you're absolutely correct. The higher pressures seem to provide a better ride.
07-29-2022, 09:46 PM
