tire pressure

Dan, I've gotten a bit nuttier since we met a HF '07 and the psi is north of 75.

In reply to eestlane and to add to Prius 07, a major engineering concern seems to be a soft/smooth ride when setting tire psi. This is what caused the problems with the Exploder from Ford. People were complaining that they rode like a truck. DUH! It is a truck. So Ford set the psi at something like 26 or 24 psi so a truck would ride like a car. Also, to echo what Dan said, I'm not recommending these pressures to anyone but myself. I only post it to say that I've ran this way for 15K+ miles with no problems. YMMV.

 

I don't think that softer ride was the reason for 35/33, since the whole concept and all other details of the design are for gas mileage: aluminum hood & rear lid, drive train design, aerodynamics, etc. etc. They wouldn't just have said, OK we went to great pains for fuel efficiency but just for the heck of it lets recommend lower than optimum tire pressures for a good ride.

 

I wouldn't be too sure of that. They may have been thinking that someone could come in and take a test drive and say, "It's gets decent mileage but it rides like a hay wagon." Let's face it, the majority of people-especially most Americans- want a comfy ride more than they would good FE.

 

I've been keeping 42/40 in the tires, but if I could push all the way up to 70 for good FE, I'd give it a try --

Rougher ride is no problem (previous car was a 95-Wrangler), but aren't there concerns regarding stability at super-hi pressure? I drive the Prius rather conservatively, still -- maybe hi pressure on interstate hiways, but lower in town? Or vice versa?

 

Cool, keep us apprised of your results. Since your in NJ, I'd suggest you keep a tire gauge with a bleed valve. If you get the snow flake icon (ie below freezing), drop the tire pressure down to 35 or whatever the door jam and your winter tires recommend. High pressure is a bad idea on icy patches, but no problem on water. Hasn't iced in Cypress in over 10 years. ;-)

Also make sure you stay on the tire rotation schedule (every 5-6k). Keep up on your alignment and also ensure that your tire pressure is symmetric. Having one side with more pressure than the other can cause a pull, mess up your wear pattern and alignment as play havoc on your MPG. Just get tire nutty and you'll be fine.

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Dan,

You remind me of a guy who aired my tires a few weeks ago.....

 

what type of gauges are you guys using? I have two digital ones, alongside a good old fashioned pen style. The reading from the digital is about the same between the two. They where cheap digitals though, anything better out there?

 

I use AccuGauge. It's an analog "clock-type" gauge. You can get them at Sears. My only complaint is that it only goes up to 60 PSI.

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I'm gradually increasing my PSI (at 44/42 now);
Looking over this threads reminded me of my dream last night --

Dreamed that all 4 tires were bulging & blistering & I immediately deflated them. Yikes, too much PriusChat! :smash:

 

Toyota as with all vehicle manufactures, have to make a compromise between ride quality, fuel mileage and safety. All of the vehicle manufactures use far less psi in the tires than what the tires will actually safely hold. This is also true of the tire manufacture recommendations.