Why inflate tires to 39 psi? I am ticked off!
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From: Iowa
2025 EQS580
Why inflate tires to 39 psi? I am ticked off!
I am getting very annoyed. For the past 3-4 service appointments (most minor), the technician at the dealer that serviced my S550 inflated the tires to 39 psi. Such air pressure is supposed to be limited to a maximum load. The normal load is 32. WHY are they doing this? Last Friday when I brought the car in for the 20,000 mile service, I specifically left orders with the service advisor to please inform the tech that I want the tires to be inflated to 32 psi.
So, when I picked up the car and started driving home, I set the display to the tire pressure monitor, and I was pissed. The tires were inflated to 38-39. I called the service advisor and complained. He said he forgot to tell me that the technician stated that "standard air pressure for the front is 38 and 39 for the rear." I said, the technician is dead wrong. Furthermore, the advisor told me that if I open the gas lid, it says what the cold/hot air pressure should be. By now, I was getting more angry. I explained to him that those readings on the lid are for load/weight the car is hauling and they are not a function of outside temperature. I also told him that if they are inflated to 32 when tires are cold, they will read about 34-35 after driving for a while and the tires get hot.
The advisor was brand new and I basically forgave him for not knowing what he was talking about. But I do not forgive the technician who worked on my car. Have any of you folks had this issue when they work on your car?
So, when I picked up the car and started driving home, I set the display to the tire pressure monitor, and I was pissed. The tires were inflated to 38-39. I called the service advisor and complained. He said he forgot to tell me that the technician stated that "standard air pressure for the front is 38 and 39 for the rear." I said, the technician is dead wrong. Furthermore, the advisor told me that if I open the gas lid, it says what the cold/hot air pressure should be. By now, I was getting more angry. I explained to him that those readings on the lid are for load/weight the car is hauling and they are not a function of outside temperature. I also told him that if they are inflated to 32 when tires are cold, they will read about 34-35 after driving for a while and the tires get hot.
The advisor was brand new and I basically forgave him for not knowing what he was talking about. But I do not forgive the technician who worked on my car. Have any of you folks had this issue when they work on your car?
Last edited by AppleFan1; Jul 30, 2015 at 12:40 PM.
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Joined: May 2015
Posts: 84
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From: Newport Beach, CA USA
2014 S550, 2015 Cadillac Escalade ESV
Yeah, add me to the annoyed list for that too... I tell dealership now to specifically NOT touch my tires or wash my car. I even take off my amg tire stem caps before going in for service.
It's not just MB dealerships; when I brought my Escalade home in February I was bleeding air out of the tires for an entire week. They must of been set to 50-60lbs...
It's not just MB dealerships; when I brought my Escalade home in February I was bleeding air out of the tires for an entire week. They must of been set to 50-60lbs...
Last edited by 714Merc; Jul 30, 2015 at 12:34 PM.
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From: New Jersey
2013 S550 4matic (AMG sport package), 2016 Corvette Stingray.
Sometimes having that extra pressure will help you avoid getting bubbles aka tire tumors when hitting potholes. However; if youre not in a location that is known to have an excess of potholes then you shouldnt have to inflate over the recommended air pressure value.
Im in NJ and my vehicle has 20" wheels , I keep my air pressure at 40psi.
Im in NJ and my vehicle has 20" wheels , I keep my air pressure at 40psi.
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AMG GTC Roadster, E63s Ed.1, M8 Comp. Coupe
First off, make sure you don't measure a warm tire. All listed tire pressures are cold tires and temperature easily accounts for 3-5psi.
Our dealer always inflates tires 4-5psi higher than listed to reduce premature tire wear (SL's are known for that). Haven't checked the S-Class
Our dealer always inflates tires 4-5psi higher than listed to reduce premature tire wear (SL's are known for that). Haven't checked the S-Class
Thread Starter
MBWorld Fanatic!
Joined: Feb 2014
Posts: 1,938
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From: Iowa
2025 EQS580
First off, make sure you don't measure a warm tire. All listed tire pressures are cold tires and temperature easily accounts for 3-5psi.
Our dealer always inflates tires 4-5psi higher than listed to reduce premature tire wear (SL's are known for that). Haven't checked the S-Class
Our dealer always inflates tires 4-5psi higher than listed to reduce premature tire wear (SL's are known for that). Haven't checked the S-Class
I am a meteorologist, and I should have knowledge of the physics involved here. Hey, they should have consulted with me on the stupid "Deflategate" fiasco.
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S600
My Ferrari likes its tires ate 35 PSI if I am doing street driving, confirmed with a probe tipped pyrometer to verify the pressures and suspension calibrations are spot on.
The F355 happens to have the same tire footprints as my S600, yet weights only 3250 pounds, compared to the nearly 5000 pounds for the S600.
I have not had time to put the pyrometer on the S600 wheels, but back-of-the-envelope math indicates 39 PSI is in the right ball park.
The F355 happens to have the same tire footprints as my S600, yet weights only 3250 pounds, compared to the nearly 5000 pounds for the S600.
I have not had time to put the pyrometer on the S600 wheels, but back-of-the-envelope math indicates 39 PSI is in the right ball park.
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From: CA
2010 CL65
Service at even best dealers even if repeat cust w/best SA, etc is suspect and requires much of own instructions/verification...been that way forever w/any car on planet....no one smart/risk-oriented works in auto industry, let alone at dealers (kinda like at inv banks despite far higher compensation and far bigger amts of money at risk (though not personal safety/health risks of cars/driving))
Irony of modern Net is any intelligent driver of >$100K cars prob knows issues and tail risks of any cars far better than any tech/SA or race car driver or MB CEO/R&D chief....wouldn't let the "expert" fallacies/gibberish fool you vs (un)common sense of own
Knowing these issues/tail risks/oppty costs is part of why I have never kept any new MB for more than 2yrs, minimizing my exposure to dealer to one annual visit for oil change/replacement of rear tires (where ~20% of time they manage to scuff a rim during process).....and shortly thereafter get rid of the ole car for a new copy....and move on....these are quite disposable/obsoleting devices, just like iPhones, but with far more profound safety risks as they decay and/or w/any post-factory "work" (think airbags/sensors, etc etc)...
Irony of modern Net is any intelligent driver of >$100K cars prob knows issues and tail risks of any cars far better than any tech/SA or race car driver or MB CEO/R&D chief....wouldn't let the "expert" fallacies/gibberish fool you vs (un)common sense of own
Knowing these issues/tail risks/oppty costs is part of why I have never kept any new MB for more than 2yrs, minimizing my exposure to dealer to one annual visit for oil change/replacement of rear tires (where ~20% of time they manage to scuff a rim during process).....and shortly thereafter get rid of the ole car for a new copy....and move on....these are quite disposable/obsoleting devices, just like iPhones, but with far more profound safety risks as they decay and/or w/any post-factory "work" (think airbags/sensors, etc etc)...
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