2011 Prius II Rough Ride?

Check air pressure?

 

Was thinking the same thing. My Prius came from the dealership with the tires overinflated. Certainly nice for mileage, but definitely makes the ride a little harsher.

 

Damn! 45 psi?! That's insane! Especially if it came from the dealer like that.

 

run 42f 40r ....its the best blend of mpg and ride quality. I still get 55-60mpg in LA driving

 

Yikes! I've heard it said that you should ignore the OEM recommended tire inflation pressures and instead use the maximum pressure indicated on the tire sidewalls as your guide. This is NOT a good idea, since in addition to chipping a tooth every time you go over a bump, you must keep in mind that the suspension system of the car was not designed with those kinds of pressures in mind (~45 psi) and the life of your suspension components will be compromised if the roads where you live aren't so hot (sorry ultra hyper milers). That said, you can split the difference and generally run tire pressures a bit higher (3-5 psi) than what the manufacturer recommends for a slight increase in fuel economy without dramatic ill effects to your bushings (or your teeth, for that matter).

Another thing to consider is the 1psi increase per 10 degree ambient temp increase rule so keep an eye on those pressures as the weather warms up.

 

I totally agree with Frank. I could not believe how harsh the ride was when I increased the tire pressure to 40 psi. 1-2 lbs psi over the recommended pressure (look for the label in the door) will give you great milage and a great Prius ride.
I Love This Car!!

 

Wow. If you guys are that sensitive and feel that 44psi makes the ride that uncomfortable then DO NOT put 17in. or larger wheels on you car or you'll likely die or have nightmares of your suspension falling apart. (just bustin' your chops)

Seriously, at 52/50psi my car still feels smooth and comfortable. Road noise is increased but the ability to glide long, get better MPG, better handling and make my tires last long is worth a little more noise.

 

I hope you checked the pressure in the morning when the tires were cold. You'd be surprised how warm they can get after just 10 miles of driving, thus raising the pressure quite a bit!

I keep my tires at 40/38 and find it's a good compromise FOR ME. Everyone's a little different with regards to comfort. I've also found that the tires themselves make a difference with regard to roughness and pressures. The tires I have on there now are much quieter and softer than others I've run at that same exact pressure. I don't know what the potential damage to the suspension might be with slightly over inflated tires, but as long as you don't go way overboard, I can't imagine it doing that much unless it's over a long period of time.

 

Reducing tire pressures from 45 to 35 PSI will reduce MPGs by several percent. Make the compromise between fuel economy, handling, and comfort that you like best.

 

I'm still on the stock struts with 132,000 miles worth of high tire pressure. They are not in good condition but they are not leaking and the car is not bouncing yet. That being said, most struts are worn after 60,000 miles so higher tire pressure has not appeared to have harmed my suspension according to the dealer maintenance checks.

Your comfort is what is important though and I recognize high tire pressure is not for everyone.

 

There are several threads on the cleanmpg.com forum about tire pressure and fuel mileage.

Personally I run 44 (max sidewall for the 15-in Goodyear Assurance Fuel Max) in front and 42 in rear. I do not find the ride that harsh or objectionable. I do think though personally, that those who go over max sidewall pressure are taking a huge gamble.

 

You are simply displaying your ignorance. There are many threads around here that discuss the benefit of increasing the tire pressure to improve the MPG.
Personally, I found the ride in my new Prius to be rather harsh for about the first 500 miles, Then it seemed like the suspension and the tires settled in. I then increased the tire pressures to 40 psi front and 38 psi rear. There was an improvement of about 1-2 MPG as well as a perceived improvement in the handling.
So, try to be a little patient and allow some time for things to settle in on your new Prius. Then try out increases the tire pressure.
... or you could chuck it all and buy a different vehicle.

 

A bit late, but.... :welcome:

45psi out of the dealer is weird, really weird.
I would start with the recommended tire pressure and go up from there one step at a time until you find a compromise between comfort and mpg.
I am personally against to go much above recommended pressure and what is written on the side wall of the tire. Consider that tire will get even more stiff as their temperature rises using them, hence increasing the psi. Check tire pressure when they are cold (i.e. turn on car, go to closest petrol station and check tire pressure then).