Ticking me off: Service Dept keeps filling my tires to THEIR Max pressure

..Instead of going by placard on driver's B-pillar! And my tires are modern ones that have 41 or 44psi cold max written on them, not the old 35psi. My car's door placard specifies 30psi front & rear cold. 33-34psi would even be better than the low 40s psi.

Should I tell them to just leave the tires alone?

Reply to
thekmanrocks
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Might want to leave them a note taped to the steering wheel center.

Reply to
Paul in Houston TX

I've always filled mine to the max for maximum longevity -- a soft ride has never seemed either necessary or desirable. Just how big a difference does it actually make?

Reply to
The Real Bev

Sometimes little, sometimes lots, depends on the vehicle.

On a light rear engine car, 30psi all round will bounce the front all over hell rather than corner smartly.

Reply to
AMuzi

The Real Bev wrote: - show quoted text - "I've always filled mine to the max for maximum longevity -- a soft ride has never seemed either necessary or desirable. Just how big a difference does it actually make?

Reply to
thekmanrocks

AMuzi wrote: "On a light rear engine car, 30psi all round will bounce the .."

I do believe GM specified 26 or 28psi front & rear for the first-gen Corvair. 30psi is not a magic number for all vehicles on the road. It is recommended by certain manufacturers for specific models.

Of course, I'd love to see a modern mechanic actually set a Corvair to 28psi. 44psi according to the tire and that bastard's going over!

Reply to
thekmanrocks

Look on the bright side. Overfilling the tires allows you to bleed the tires to get whatever psi you want. You're gonna get a more accurate tire pressure that way.

I like to fill my tires up to 42 psi. I like the snappy steering response and increased gas mileage. The tire guy I was talking to the other day told me that by increasing the tire pressure, you can increase the maximum gross vehicle weight capacity by up to 800lbs. I can't say if this is true nor would I care to test this out.

Reply to
dsi1

dsi1 wrote: - show quoted text - "Look on the bright side. Overfilling the tires allows you to bleed the tires to get whatever psi you want. You're gonna get a more accurate tire pressure that way.

I like to fill my tires up to 42 psi. I like the snappy steering response and increased gas mileage. The tire guy I was talking to the other day told me that by increasing the tire pressure, you can increase the maximum gross vehicle weight capacity by up to 800lbs. I can't say if this is true nor would I care to test this out. "

Well, I believe that the goal should be an optimized contact patch. The vehicle mfg. placard cold pressure might be slightly below that required for optimum patch. And the tire's max cold pressure is likely to result in too small a patch, and accelerated center tread wear, except under full weight load.

So I try the vehicle mfg pressures, and adjust up from there after several trips. That also goes for non-OEM tire & wheel sizes. The chalk stripe test is also useful, but may not indicate what will happen in a tight turn at over 50mph.

But absolutism toward vehicle mfg pressure or tire max pressure are not advised.

Reply to
thekmanrocks

Trying out different pressures seems like a good idea. I typically will keep it high. I can't say if it increases gas mileage but at least it reduces the chances of being under-inflated.

Reply to
dsi1

dsi1 wrote: "Trying out different pressures seems like a good idea. I typically will keep it high. I can't say if it increases gas mileage but at least it reduces the chances of being under-inflated. "

When your tire pressures are below the pressures listed on that door-pillar sticker, they're under- inflated.

Reply to
thekmanrocks

dsi1 wrote: " The tire guy I was talking to the other day told me that by increasing the tire pressure, you can increase the maximum gross vehicle weight capacity by up to 800lbs. I can't say if this is true nor would I care to test this out. "

That "tire guy" is dispensing DANGEROUS advice.

Reply to
thekmanrocks

Beats me if it's true or not. OTOH, the guy did go to tire school.

Reply to
dsi1

"tire school". Hah!

Teaches you how to judge tread, dismount and mount tires, and fill them with air. Nothing about the difference between door sticker pressure and the max allowed printed on the tire sidewall.

Reply to
thekmanrocks

I know nothing about the curriculum of tire school. What year did you graduate?

Reply to
dsi1

dsi1 wrote: - show quoted text - "I know nothing about the curriculum of tire school. What year did you graduate? "

I didn't go to tire school, smarty. But my description is probably apt. Where to set tire pressures is probably glossed over in the coursework. Just fill to what is stamped on the tire side wall. Done.

Reply to
thekmanrocks

Says on my tires, 41 PSI. I run them at 41.

Reply to
JR

JR wrote: - show quoted text - "Says on my tires, 41 PSI. I run them at 41. "

I used to think that way, until 16 years ago. I then expanded my periphery vision and noticed the words "Max. Cold Pressure" next to the number.

Try the pressures listed on the placard down on your car's B-pillar - below the strike post. Add a couple PSI to those numbers, then report back to us.

Reply to
thekmanrocks

I see, you think that going to school and getting educated is for suckers.

Reply to
dsi1

______________

It's not everybody, no. Not a traditional 4-year degree, no. Unless you plan on going into a career in education, medicine, engineering, or law, it's a waste of money. I hold a "OPIM"(Operations and Information Management) degree that didn't teach me a DAMN thing about how to fix or build computers. I learned more about those things by a combination of troubleshooting my relatives' PCs and what a good friend has taught over the last year, than a bachelors degree could ever impart.

But this thread is about tire pressure and common sense. And blanketly setting pressures to the Maximum Cold Pressure stamped on the tire is incorrect - unless the vehicle placard specifies the same as the recommended setting.

I know this, because I used to do the same thing, and then some! On a car I had long ago, with tires marked 35PSI cold max, I used to put up to 40 in those bastards! LOL The trunk sticker specified

35PSI as the recommended, but I paid little attention to it 20 years ago. Now, the B-pillar(or trunk, or owners manual) is always the first place I look for correct cold pressure settings - even if the tire & rim package was changed from OEM size. I then go up from there, as much as is necessary.

Something that requires more common sense than "education".

Reply to
thekmanrocks

______________

It's not for everybody, no. Not a traditional 4-year degree, no. Unless you plan on going into a career in education, medicine, engineering, or law, it's a waste of money. I hold a "OPIM"(Operations and Information Management) degree that didn't teach me a DAMN thing about how to fix or build computers. I learned more about those things by a combination of troubleshooting my relatives' PCs and what a good friend has taught over the last year, than a bachelors degree could ever impart.

But this thread is about tire pressure and common sense. And blanketly setting pressures to the Maximum Cold Pressure stamped on the tire is incorrect - unless the vehicle placard specifies the same as the recommended setting.

I know this, because I used to do the same thing, and then some! On a car I had long ago, with tires marked 35PSI cold max, I used to put up to 40 in those bastards! LOL The trunk sticker specified

35PSI as the recommended, but I paid little attention to it 20 years ago. Now, the B-pillar(or trunk, or owners manual) is always the first place I look for correct cold pressure settings - even if the tire & rim package was changed from OEM size. I then go up from there, as much as is necessary.

Something that requires more common sense than "education".

Reply to
thekmanrocks

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