Many years ago I found the standard 30 psi that we used to run in the old F70-14's and 15's was way too high for these modern low profile radial tires like the ones used on the C3's.

I experimented with different pressures in my big block '71 and found I get the longest tire life running 24 psi in the front and 20 psi in the rear. My tires wear perfectly even at those low pressures so I feel I'm running the best pressures for my situation.

How much pressure do you guys run?

 

34/34 on my 18"

 

20/24? wow... I run 32

 

32 all around.

 

32 psi

 

30 psi at all 4 corners.

 

34 psi 235/55 x 17 tires

 

I would not run less than 30 PSI on any tire on any car. For the max tire life and best fuel mileage as well as tire integrity a Michelin engineer told me years ago that you should run the most pressure (without exceeding the tires max pressure) you can tolerate ride wise and that also will allow even tire wear across the contact patch. Back in the 90's, I did just such a technique with a Goodyear Eagle GT+4 ZR tire running about 40-44 PSI and the tire lasted 50,000 miles which was unheard of back then for a Z rated tire. The goodyear shop could not believe it when I took them off the car.

 

35 all around.

 

Ford tried low pressures too- Just sayin-

In May 2000, the U.S. National Highway Traffic Safety Administration (NHTSA) contacted Ford and Firestone about the high incidence of tire failure on Ford Explorers, Mercury Mountaineers, and Mazda Navajos fitted with Firestone tires. Ford investigated and found that several models of 15-inch Firestone tires (ATX, ATX II, and Wilderness AT) had very high failure rates, especially those made at Firestone's Decatur, Illinois plant. This was one of the leading factors to the closing of the Decatur plant.[1]

Joan Claybrook, who was the president of the public advocacy group Public Citizen and previously an Administrator of the NHTSA, stated before the Transportation Subcommittee United States Senate Committee on Appropriations on September 6, 2000, that, "there was a documented coverup by Ford and Firestone of the 500 defect".[2] This refers to the 1970's debacle that had already tarnished Firestone's reputation.[3] Also Clarence Ditlow; Executive Director for the Centre for Auto Safety in his statement before the Senate Committee on Commerce, Science and Transportation in Washington D.C., September 20, 2000[4] stated "Emerging Information shows that both Ford and Firestone had early knowledge of tread separation in Firestone Tires fitted to Ford Explorer vehicles but at no point informed the NHTSA of their findings". [5]
Possible causes

The Ford Explorer was first offered for sale in March 1990. Ford internal documents show the company engineers recommended changes to the vehicle design after it rolled over in company tests prior to introduction, but other than a few minor changes, the suspension and track width were not changed.[6] Instead, Ford, which sets the specifications for the manufacture of its tires, decided to remove air from the tires, lowering the recommended pressure to 26 psi.[7] Low air pressure leads to increased heat; heat can damage the tire.[8]

The failures all involved tread separation[9]—the tread peeling off followed often by tire disintegration.[10] Tread separation, due to the interaction of steel and rubber tire elements, has been a challenge in radial tire design since their development by Michelin in 1946. In 1968, Michelin proposed a nylon cap over the steel elements to counteract this, and Firestone adopted this nylon cap design in 2000, following investigation by the United States Congress.[11]

 

 

Recommended tire pressure is on a sticker on the driver's door...the 81' figures are 35PSI for front, rear and spare....

 

that is what i run regardless what vehicles i drive, unless of course it is a light duty truck or pick up, etc.
I feel for the street that is the best all around pressure for ride and handling, especially on "dd".
Anything less i feel may be unsafe and anything more is too hard of a ride to enjoy....JMO.....

 

Wow, you must really like a hard ride, if you follow those pressures. Anyone running that high of a pressure should drop down to 30 psi and you will be amazed at the difference. IMO tire pressure stickers list those high pressures so that you will get the least rolling resistance from your tires to give you the most optimum gas mileage, which does not always equate to a decent ride and good handling.....Again JMO.........

 

42-44PSI on my 15" Mickies. rides great and handles great.

 

After rereading your post, i would not run pressures as low as you regardless of a SB or BB, simply because there is the possibility of having the tire come off the rim when driving, especially when going around curves etc. at normal or higher rates of speed.
Driving a big truck, it has happened more than once to me on some of the trailers. And those tires run 90 or 100 lbs pressure...and no i dont run 30 lbs in them...

 

me too.

 

30..................my kidneys don't appreciate 35

 

I run 30psi at the corners and agree with terry82

 

I run 26 all around for a better ride. I know that a lower pressure like this will promote faster treadwear, but given the fact that I drive my C3 approximately 2000 miles a year, I will have to replace the tires due their age well before the treadwear indicators tell me the tires need to be replaced.