Vehicle tire pressure

[Mark42]

Yesterday I had my tires balanced on my 98 Town Car. The service tech put 40+ psi in each tire cold. I asked him to set the pressure to 32psi as per the Lincon spec and he told me "its not the car, its the tire. This tire says 50psi max so that is what you should set it to" I could not believe my ears. I didn't want to argue so I let it go. After paying my bill, I let the air down to 32 in the parking lot and left.<br /><br />Next I went for an oil change and the guys (two techs working on car) one puts 40 psi in the drivers side, the other tech fills the passenger side to 45. When paying the bill, I asked what pressure they set it to because I had just set them all to 32. He goes to the shop and comes back saying "they set them to 32". So I check them and find the 40/45psi settings. Again, I let them down to 32.<br /><br />Two times in one day two different service centers set the tire pressure wrong on my car. I began to wonder if I was wrong, and went to the Falken and BF Goodrich tire websites to see what they say about tire pressure (I have Falkens 255 50 17 on my car). Both say to follow the automobile manufacturer's listing for tire pressure. <br /><br />I called the tire shop and talked to the service manager, he agreeded that the pressure is by car manufacturer, not max listed on the tire. He said he would talk to the tech.<br /><br />So, check your tires after service because the people who should know obviously DO NOT KNOW. You may be running around on 70psi in your light truck tires just because that is the max rating.<br /><br />Now when towing my trailer (1400 lbs), I am not going to raise the tire pressure anymore. The hitch has only about 90-100 lbs on it, less than if I had 4 passengers in the car. Lincoln does not list a standard/loaded tire pressure spec. It just lists 32 front and rear. The lincoln also has air bag rear springs so it self levels to load.<br /><br />I will pay much closer attention to the tire pressure on my cars after yesterdays experience.

 

[vranasaurus]

Re: Vehicle tire pressure

Don't worry I had the same problem when I took my silverado to the dealer to get the oil changed they set the pressure to 44 PSI when it is supposed to be 35 PSI. The vehicle is rated for it's loads at the reccomended tire pressure.<br /><br />It is amazing how many tire idiots don't know this. I sold tires at one time and I had to explain this to customers. After I showed them what the sticker on their door said they all believed me. I bet that your car was riding a little rough with close to 50 PSI.

 

[tommays]

Re: Vehicle tire pressure

well i run my silverado at 40 on a 44 pound rated tire <br /><br />they are wearing flat the ride is fine and i get better gas mileage and a more stable ride.<br /><br />plenty of people ran there Ford Explorers at the factory rateing and paid a pretty big price<br /><br />most auto makers are concerned about ride comfort more than stabilty<br /><br /><br />tommays

 

[Mark42]

Re: Vehicle tire pressure

I have read that when a tire is "up sized" that results on a larger contact patch on the pavement. Because there are more square inches of contact are, the tire pressure can actually be lowered a pound or two. <br /><br />I am now on my second set of "up sized" Falken tires. I ran the recomended pressure by Lincoln and the tires wore evenly and lasted for 60k miles. Not bad for a two ton vehicle.

 

[JohnRuff]

Re: Vehicle tire pressure

Tire pressure haunted me most of my life. So one day I decided to fine out what was really correct. One thing is for sure - if you do not know the real weight of your venicle - you will never know the correct tire pressure. And you need to know the weight on the front tires and the rear tires seperately.<br /><br />Here is a really good article on it -- and includes the variable of when towing:<br /><br /> http://www.trucktires.com/us_eng/library/downloadables/RV_bro/WeighForm.pdf

 

[rwidman]

Re: Vehicle tire pressure

Originally posted by JohnRuff:<br /> Tire pressure haunted me most of my life. So one day I decided to fine out what was really correct. One thing is for sure - if you do not know the real weight of your venicle - you will never know the correct tire pressure. And you need to know the weight on the front tires and the rear tires seperately.

Why not use the pressure recommended by the manufacturer? They have design engineers, they consult with the tire manufacturers, and they do testing. Most of us don't have those resources.

 

[ZmOz]

Re: Vehicle tire pressure

I had a new set of oversized tires put on my truck by Les Scwab a few months ago. (big tire chain in the west) Normally the people that work there are very knowledgeable and provide good service. All 4 of my new tires had different pressures...ranging from 30 to 50. It felt pretty squirrely on the road, I thought it was just the new tires. Didn't check the pressure for about a month because surely they would have done it right... Put them all at 35 and it rides MUCH better.

 

[Mark42]

Re: Vehicle tire pressure

I just checked my wife's Mountaineer. 35 front, 45 rear. Idiots are all around us.

 

[amirm]

Re: Vehicle tire pressure

Similar story here. I bought a new SUV (Land Rover LR3) to tow our new boat. The SUV manual suggested to increase the rear pressure to 42 psi when towing. Before putting more air in the tires, I checked them with the air guage and was shocked when it went past the 60 PSI maximum that the guage measured. Thinking the guage was bad, I checked it on my wife's car and it showed the right amount. Just to be sure, I bought an electronic one and still saw the same amount. And to top of this off, all 4 tires were filled this way from the dealership/manufacturer!<br /><br />So lowered the fronts to 35 and rears to 42. The handling suffered a bit but overall ride is more comfortable. I must say, I do miss the way it handled before . But feel better running the tires at the recommended settings.<br /><br />Amir