HyperInflation... Anyone ???

[astroturf]

Howdy All,

Is anyone running more air pressure in their tires than the Manufacturer recommends?

Is anyone running more air pressure in their tires than the max inflation listed on the sidewall?

What are your MPG results, Tales of Terror, Observations, Size/Specifications?

Thanks, Jim

[VanGoGo]

Seems like that could lead to uneven tire wear (center tread wearing faster), but I haven't tried it personally.

[astroturf]

Man, You Guys are on FIRE.

Slow down some, I can't keep up.

Guess this is not the forum for this type of discussion.

Sorry, Jim

[Kidhauler]

I always run at max inflation on the sidewall rating but I do not over inflate. I worry about wearing the tires out or having a tire peel apart at speed. You will get better mileage gains by changing how you drive and tuning the van up than by running 50psi.

[MountainManJoe]

I run 40psi to save fuel, but it's a bumpy ride.

[mdmead]

You will get better mileage gains by changing how you drive and tuning the van up than by running 50psi.

Yeah, that and if you are wearing tires at a faster rate, that is going to offset any mileage gain anyway.

[astroturf]

VanGoGo,
I agree if not properly executed it could lead to quicker tire center tread wear.

Kidhauler,
By running the sidewall max of the tire, you are over-inflating according to the manufacturers specs. That can also vary based on the tires max pressure... I.E. 35, 44, 51 psi for P Rated tires.

TB,
I ran my last set of tires at 41 psi, That was just about the max that I could safely endure, Both for comfort and tread wear.

mdmead,
What can be said? After driving this van for the past 66,992 miles over the last 2 1/2 years, I have achieved a lifetime MPG of 17.8

Oh, and PS Guys... The last set of tires that I conducted these tests with Traveled 64,500 miles. Not bad for a 50,000 mile tire.

Safety First...

Jim

[Kidhauler]

How is running the max rating on the tire that was put there by the company that made the tire over inflating it? Depending on the sidewall stiffness and the size of the tire you should run the specs on the tire not what is written on the door as that is for the stock tires not whatever you put on aftermarket.

[astroturf]

Kidhauler,
No disrespect meant, But if you run your tires at max sidewall inflation pressure, you are over-inflating the tire, according to the vehicle manufacturers specs for that vehicle.

My Van calls for 38 psi (Cold Pressure), in a 215/70 16 tire.
My current tire is that size, made by Michelin.
Model: Michelin LTX MS (First Gen). It has a sidewall psi max of 35 psi.

Did I buy the wrong tire?

Thanks, Jim

[Kidhauler]

No offense taken those are the same tires I have on my van. In the case of those tires they call for 35psi which happens to be what the stickers called for. But on one of my old vans the tires called for 42psi if you ran them at 35 they cupped badly the centre of the tire lifted.

If the tire is not stock size then run the sidewall rating. Most tires are rated for 35psi so it isn't a issue. If you ran the tires at 38 as the truck says but the tires have a sidewall rating of 35 then you would be over inflated but probably not enough to make a difference. Don't forget there is a fair bit of difference your tire can handle with elevation changes and road temp. For example if I filled the tire here in Vancouver on a chilly day at sea level and then headed south in one days drive the temp could go up by 30 degrees celsius and have elevation changes of several thousand feet at grants pass Oregon and at the grape vine in California. But the tires handle that difference with no issues.

However if you start the same trip with a tire that is 10 psi over inflated you might peel the tread off somewhere in the sacramento valley or southern oregon.

[astroturf]

Thanks Kid,
I don't want to PO anybody here. Thanks Again.

I installed the tires on the 25th of April. I set the pressure at 38 psi cold (Manus recommended psi). They rolled like Jello, and rode like Marshmallows. I than begin to research and test.

I found the Over-Doing It Point this morning with 48 psi cold. It was a bit to floaty for me (just too vague in the steering response department). I will follow up with a cold psi of 47 tomorrow morning, as I have found that 46 is still too soft.

I have found that at the higher pressures, the tire runs cooler, is better protected against sidewall punctures, and still offers greater comfort than my old tires which I ran at 41 psi cold.

Time will tell about tread wear, I take lots of pix and keep pretty good notes.

Thanks, Jim

PS The Max increase that I have seen so far, besides 1 psi per degree of increase in outside air temp, Has been about a 5 psi increase after some 70 mph Highway trips.

[Kidhauler]

At 10 psi over you will be running down the centre of you tire badly. You will lift the outside treads off the pavement. The tire will run cooler because less is touching the road however by not letting the sidewall flex and do it's job of keeping the tread on the road going around corners. The tires you bought are great for load capacity and lots of grip due to a good sidewall thickness and the nice soft rubber compound that makes them great in snow. But they are not good for mileage. I know these are expensive tires but have you thought about going with a slightly narrower tire and look for some low rolling resistance tires they can save you n mileage as they take less energ to turn. It would be allot safer than the crazy pressures you are trying to use in a effort to save a very small amount of gas money. You will probably burn off the centre treads of what was probably $500 worth of rubber.

What rear end do you have in your van? If you have a tow pack and dont tow a heavy trailer then maybe a rear axle swap with higher gears would be a idea. I have had 4 vans one of which didn't have the tow pack and it had a taller backend and got 4mpg better at least.

Honestly I am concerned for your safety at that kind of pressure. A tire that hard is actually easier to put a hole in than a soft tire plus you increase the chance of a blowout hitting a pot hole since the tire can't flex. I understand where you are coming from the price of gas is killing us all but just be safe.

Ever thought about propane or natural gas conversion?

[Kidhauler]

On a more important note Canucks just won in overtime!!!!!!!!!! !

[astroturf]

On a more important note Canucks just won in overtime!!!!!!!!!! !

Who did they beat?

PS 3:42 gearing, No tow pack or hitch.

[1Gary]

Hi Jim.

One thing I am very sure about.KH has always been head and shoulders about safety.I suggest you seriously consider what he is saying.I too don't want to see you get hurt over pennies of gas.