Optimum tire pressure?

[Mooneggs]

I'm about to make a 2400 mile road trip and I was looking for advice on how much tire pressure I should be running...

I am using Yokohama Avid V4S tires in 205/55/15 on stock 5 spoke rims...

obviously I want to get the best possible mpg but I don't want to have my tires overpressurized so that they wear out in the middle...

right now the tire pressure is 30psi and the tires are rated at 44psi maximum...

so should I leave it at that or raise it to 32-35 psi??

[mitmaks]

you should be fine with 35-37psi, youll get better mpg and car will handle better.

[fowljesse]

Remember how my car handles?
I've been running about 42 PSI for about 6 months. For this trip, they won't wear significantly.
If you're not afraid, try 2oz. Acetone per fill up. You'll get about 3 MPG more.
And, believe it or don't... fold in your mirrors for another 1-2 MPG, and leave the windows up. This shouls make up for the weight of the stuff you're bringing for me

[Mooneggs]

well I remember a time when I went through a set of tires because I had them inflated to 42-44 or something and it wore out the middles...

lol I have no a/c so the windows will be down the whole trip unless it's raining... and if I decide test the limits of my top speed I usually fold in the mirrors and roll up the windows

on previous road trips I can drive as fast as I want and I still get between 28-30 mpg... but if I drive a consistent 72 mph I can get up to 35 mpg so that may be what I end up doing the majority of the trip

[npspears]

on previous road trips I can drive as fast as I want and I still get between 28-30 mpg... but if I drive a consistent 72 mph I can get up to 35 mpg so that may be what I end up doing the majority of the trip

Is this in your KLZE? If so I find that pretty dang impressive. I about 37 mpg highway in my 99 Saturn sl2 DOHC auto. I'm sure the saturn weighs more but still

[Volones]

There is a lot of discussion about this, but I haven't heard of anyone wearing out the inside of their tires recently. Older bias-ply tires did have that problem, and older radials could also, but newer ones (like the last 5 years or so) don't seem to wear the middle excessively as long as you're still under the max pressure recommended by the TIRE manufacturer. I would run them at 40-44psi and enjoy the better mileage (if not the slightly harsher ride )

Have a fun trip!
Vol

[Daninski]

What about the manufacturers recommended on the door sill? 42 psi sounds high to me.

[Mooneggs]

I ended up inflating at 36 psi... and I ended up averaging about 31-32 mpg... not bad

[Nd4SpdSe]

My fronts are rated for 51psi and my rears 44, I'll usally run them about 5psi less than max. The stiffer ride doesn't bother me but I really like the better handling and steering responce, and the plus is better milleage too.

[Whisper]

What about the manufacturers recommended on the door sill?

Yeah. If anything, I'd go with that for daily driving and long trips.

[Volones]

What about the manufacturers recommended on the door sill? 42 psi sounds high to me.

That number is a compromise between ride comfort -handling - fuel economy. Lower pressure improves ride comfort at the expense of the other two, while higher pressure improves handling (stiffer sidewalls) and fuel economy at the expense of ride comfort. You can run your tires as you wish, but I have not read anything about inflating them to the tire manufacturer's max being dangerous at all.

Vol

[Ryan]

Doesn't it say on the sidewall of the tire? Mine are 35 and thats where they are...

[Whisper]

but I have not read anything about inflating them to the tire manufacturer's max being dangerous at all.

It's not recommended to inflate to the max pressure indicated on the sidewall, because as tires heat up during driving the pressure increases. If it goes too far past the maximum, the tire's durability decreases, and you'll also likely cause uneven wear. Also I imagine overinflated tires cause more suspension wear, since they're no longer soft enough to absorb a lot of the road surface imperfections.

[bdr2k5]

I ended up inflating at 36 psi... and I ended up averaging about 31-32 mpg... not bad

its that on a ZE!?
my best on highway its around 27mpg driving at 3500rpms.. do you have 4.11 gears and 5th gear swap?

[Mooneggs]

its that on a ZE!?
my best on highway its around 27mpg driving at 3500rpms.. do you have 4.11 gears and 5th gear swap?

yes I have a 626 tranny mated to my ze.