Front tire pressures using 175's all around?

[SubSlr88]

Any one running rear rims on the front and 175 tires on all four corners - what pressure did you settle on for the front? I'm going to go this route and think 29lbs may be a bit low and add a little to the steering difficulty.

Any one have any suggestions if you've done this. . . Thanks!

[Old smart]

Proper tire pressure is a matter of contact patch and the weight that the contact patch supports. The Euro pulse weighs the same as the N.A. smart, and uses 175/55-15 tires on the front. The proper pressure for the pulse fronts is 1.8 bar or 26psi.

N.B. The pulse's 195/50-15 rears are 2.2 bar or 32psi. Remember that the Ford Explorer/Firestone flap was the result of running tires at the wrong pressure.

[smartah]

I've been running this way for several months with 32psi in the front. Tried 36 but ride was too stiff.

[RussBarnes]

I have Michelin 185/60-R15's that I have run at 36 psi all around for the last year (5,000 miles), but we have pretty smooth roads here in TN and Michelins ride better than Conti's.

[Godfather]

Stock rears on all four corners, 30 front, 36 rear, haven't seen a mileage difference yet with the extra width on the front, car sure feels better.

[John_H]

Running with such high pressures, has anyone checked for evenness of wear? Too high a pressure leads to a smaller contact patch with the road which - depending on tire - can result in a much smaller amount of the tire experiencing wear.

Why use wide tires if you pressurize them to where they act as narrow tires?

[rfernatt]

I'm using 195/50s all the way around and at about 28 psi front and 34 psi rear.

[RussBarnes]

In my earlier years I built race cars and have sold literally thousands and thousands of tires. I have driven race cars, cars and trucks for about 48 years and owned about 75 street cars, so I know a little bit about tires. I run 36 psi all around because we have smooth roads in TN and I want MPG. I also have a lot of experience with Michelin street tires and know they have always given me superior life. In 5k miles I can't visually detect any wear, so since I drive about that many miles a year they may have to be replaced for age before they wear out, but that is yet to be determined. The other factor is the locked in rear camber, which may wear the inner edges of the rears, but to date it doesn't show. If they wear since I have four equal tires I can rotate them. This isn't a high performance race car running on the edge, I haven't shot them with my temp gun to verify that the centers are the same reading as the shoulders, but frankly I don't give a damn what it is.

Now if you are in rough roads, areas of a lot of rain causing slippery conditions, ice, snow, etc., don't do this without doing some serious tests, even if it is nothing more than running through a water puddle and looking at the tire patch in the wet, that will get you close.

[Big Panda]

Originally Posted by John_H

Why use wide tires if you pressurize them to where they act as narrow tires?

To only answer your question: to have more of a 'cushion' between the road and the wheel. I'm not advocating that, only saying that's more than likely the reason.

[SubSlr88]

Originally Posted by Old smart

Remember that the Ford Explorer/Firestone flap was the result of running tires at the wrong pressure.

I was involved with that mess and actually made out very well. The Firestones I had were replaced with Goodyears after 25,000 miles.

My brother-in-law made out even better, he was on a summer trip and had a Ford dealer install a new set of Michelins, replacing his Firestones with almost 20,000 miles.

I'm pretty cautious with tires and check the pressures routinely.
Thanks to those who responded with some great info.