- Joined
- June 17, 2004
- Messages
- 24,267
- Reaction score
- 4,737
- City, State
- Knoxville, TN
- Year, Model & Trim Level
- 98 Limited AWD 302
Tires come in various MAX pressure ratings, most are 44psi these days. The stock 15's were 235/75/15, a taller profile tire than the later 16's that were 255/70/16. The profile(75, 70) is a primary stability factor. A 45 series tire(old Mustangs with 245/45/17's) is more stable than a 225/60/16(stock on similar age Crown Vics and Lincolns) tire. That 15% series difference makes 3" of height difference. Each 5% is about one inch.
I just wore out a set of Michelins last October, the LTX MS2's I believe, in 22-23000 miles, eleven months, at work. I chose a 255/65/16 instead of the stock 255/70/16 size. That's an inch shorter tire, and it was more stable than the original size, but the speedometer was off just a hair, maybe 3mph at 65mph or so. All the 15" stock tires were the same 29" diameter, with the same speedometer error(stock). So I don't mind a tire in the 29"-30" height for myself. I changed this last time to a 245/70/16 in a Cooper Discovery AT3, 29.5" tall, just a hair shorter than stock. These are all 44psi MAX tires, for even wear they have needed about 36psi in front, and 33-34psi in the rear. That produces the least uneven feeling from the front and back, and even steering response. As the pressure in front gets closer to the rear, steering feels slower, the back feels more loose(fishtailing).
I just wore out a set of Michelins last October, the LTX MS2's I believe, in 22-23000 miles, eleven months, at work. I chose a 255/65/16 instead of the stock 255/70/16 size. That's an inch shorter tire, and it was more stable than the original size, but the speedometer was off just a hair, maybe 3mph at 65mph or so. All the 15" stock tires were the same 29" diameter, with the same speedometer error(stock). So I don't mind a tire in the 29"-30" height for myself. I changed this last time to a 245/70/16 in a Cooper Discovery AT3, 29.5" tall, just a hair shorter than stock. These are all 44psi MAX tires, for even wear they have needed about 36psi in front, and 33-34psi in the rear. That produces the least uneven feeling from the front and back, and even steering response. As the pressure in front gets closer to the rear, steering feels slower, the back feels more loose(fishtailing).