do dealers purposely under inflate tires to give cars a smoother ride?

holden j caufield

Diamond Member
Dec 30, 1999
6,324
10
81
went car shopping with someone and almost every car seemed like the front tires are under inflated. Bought the car and sure enough the fronts were 5lbs less pressure.
 

EvilYoda

Lifer
Apr 1, 2001
21,198
9
81
A lot of GTO owners on LS1GTO.com commented that their tires were OVERinflated...mine were upwards of 10psi too high!

Who knows, they're just bad with numbers :p
 

mattocs

Platinum Member
Jan 25, 2005
2,246
0
0
That'd odd. I've never even thought of that. I keep my tires about 4 PSI over for the longer tire life and better gas mileage.
 
Sep 29, 2004
18,656
67
91
Originally posted by: OBW96
That'd odd. I've never even thought of that. I keep my tires about 4 PSI over for the longer tire life and better gas mileage.

Is that safe to do? I just want 1-2 psi over.

Actualyl, engineers always over estimate thigns for safety factors. 20% is a common overestimate. So, 4 psi over on a 30 psi tire isn't that bad.

Might be a good idea to check tire pressure after 1 hour of highway driving on a hot day.
 

mercanucaribe

Banned
Oct 20, 2004
9,763
1
0
Originally posted by: IHateMyJob2004
Originally posted by: OBW96
That'd odd. I've never even thought of that. I keep my tires about 4 PSI over for the longer tire life and better gas mileage.

Is that safe to do? I just want 1-2 psi over.

Actualyl, engineers always over estimate thigns for safety factors. 20% is a common overestimate. So, 4 psi over on a 30 psi tire isn't that bad.

Might be a good idea to check tire pressure after 1 hour of highway driving on a hot day.

Those numbers aren't for safety. The number on the sidewall is the safe psi limit. Running higher than standard pressure will only result in uneven tire wear. I still run mine about 3psi over.
 

NutBucket

Lifer
Aug 30, 2000
27,124
613
126
The numbers are usually a compromise of handling, load capacity and noise. I found all my tires inflated to 30psi. Recommended is 35/32. I'm running them at 38/35. Handles a heck of a lot better then it did when I drove it off the lot but the tires suck anyway.
 
Sep 29, 2004
18,656
67
91
Originally posted by: mercanucaribe
Originally posted by: IHateMyJob2004
Originally posted by: OBW96
That'd odd. I've never even thought of that. I keep my tires about 4 PSI over for the longer tire life and better gas mileage.

Is that safe to do? I just want 1-2 psi over.

Actualyl, engineers always over estimate thigns for safety factors. 20% is a common overestimate. So, 4 psi over on a 30 psi tire isn't that bad.

Might be a good idea to check tire pressure after 1 hour of highway driving on a hot day.

Those numbers aren't for safety. The number on the sidewall is the safe psi limit. Running higher than standard pressure will only result in uneven tire wear. I still run mine about 3psi over.

Oh, so that will asue the tire to bulge, in the manner obvious to most.... More wear i nthe center then? Interesting.