Not happy with ride on new Prius

You can fiddle with your tire pressures to see if that can improve the ride, did you drive the car before you bought it?

 

Those look to be the 17" low profile tires. They tend to need lower pressures than the 15", and even then the ride is firmer.

 

I think the Prius would hit the sweet spot with 16" wheels and something like 205/55-16 tires. I think that might give a good balance between ride and handling, and look good too.

 

I love the colour.

 

When it comes time to replace the tires, maybe consider 205/50R17. They have OD a little bigger (virtually same as 195/65R15), and being narrower with a bit more sidewall height, should improve the ride, and mpg.

 

I wasn't thrilled with the ride, either. But, after installing the TRD Springs and Anti-sway-bar, I couldn't be happier!

 

Set your cold tire pressure all around to 33 psi, it will be much better. These low profile LRR tires are stiffer than the 15" wheels and tires.

 

+1
I went from a 2012 Prius Five with the 17" stock tires to a 2012 Plug-in Prius with the stock 15" tires.
Hands down- the 15" tires are a much nicer ride. Those stock 17" LLR tires are like riding on solid rubber - especially if you over inflate them at all...

The 17" tires get worse mpg than the 15" tires...

 

You didn't notice the difference in the ride during the test drive? I'm assuming you didn't take your new Prius on the same roads you travel on a normal basis.

 

The TRD Springs are actually stiffer and lower the ride height.

SCH-I535

 

Absolutely not. All lowering springs need to be higher rate (often significantly) over the reduced suspension stroke in order to provide enough resistance to keep the car from bottoming out for similar forces.

In the case of a strut-type suspension like the Prius, they often need to be much firmer because lowering the car significantly increases the roll-couple (much more so than that of a typical double-wishbone or multi-link design)... and you need to increase the rate just to even manifest the same degree of roll-resistance, irrespective of the bottom-out considerations mentioned above.

And firmer/higher rate springs will worsen the ride.

 

I like the ride in my 2008 and my 2012.

 

Bottom line, if you like a sporty and firm ride, the 17's with TRD Springs and Anti-swaybar are the way to go. If you enjoy a softer ride, the 15's are the only way to go. I prefer a stiffer ride with less sway and more control like you would find in a 328ci. With that said, an unmodified suspension with 17's is not going to make you happy.

Unlike the standard 17's, I have the TRD Forged Rims. They improve the ride substantially over stock 17's. Here is a quote from wisegeek.com which can explain it better then I can:

Forged wheels are strong, dense, yet very light wheel that high performance car enthusiasts use for their cars almost exclusively. The term “forged” refers to making an alloy wheel by forcing a raw block of metal into a shape with extreme pressure. Forging is an expensive, multi-stepped process.


Most of the alloy wheels on the market are one-piece cast wheels, not forged wheels. The difference between the two processes is that casting involves placing liquefied aluminum into a mold. As the aluminum cools, it is formed into a wheel. There are several different ways to accomplish this, including gravity casting and low-pressure casting.


The main benefit of forged wheels over cast wheels is the weight. To understand the benefits of lighter wheels, it is necessary to understand the differences between “sprung weight” and “unsprung weight” in relation to your vehicle. Sprung weight is supported by the suspension, including the transmission, engine and chassis. On the other hand, unsprung weight refers to everything else, including the suspension system and the components attached to it. Surface imperfections in the roads place force on unsprung weight, which then reacts with its own movement. The less unsprung weight in a vehicle, the less it is affected by the road and other outside forces.

 

So do you actually know how much lighter your forged wheels are supposed to be?

Because the tires (which contribute to ~50% of the wheel weight of a cast 17" wheel/tire combination) stay the same (you can get lighter tires, but that's not the issue at hand). And on average, forged parts are ~25% stronger in tensile strength, implying that a forged part built to the same load duty should weigh ~80% of the cast part. Meaning that a forged wheel/tire combination should only be ~10% lighter than than an equivalent cast wheel/tire combination. Of course, this doesn't even take into account the brakes/rotors/hub/studs/CV joint/etc. that remain the same to reduce the unsprung mass reduction to probably something less than 5%.

I have neither of the 17" wheels in question, so all this is moot to me. However, I find the claim that forged wheels make for improved ride quality questionable. I have seen no version of this claim in any other car community.

In contrast, the most-cited reason in favor of forged wheels is the increased toughness over the relative brittleness of cast wheels in applications where failure would be catastrophic, like track duty.

 

I will research it again and get back to you. When I researched it in the past, I remember finding that they were the same weight as the stock 15's. However, the forged rims do make a difference in the ride over cast aluminum. Ask any motorcycle rider and he would choose the ride with forged over cast. I have ridden motorcycles in the past with nothing different then forged rims over stock and a long ride with the same bike reduced fatigue... Not as jarring! If you live in Florida, and you want to bring some stock 17's over, we can switch them out for an hour and compare the two.

 

Have you actually checked the pressure yet, since delivery?

Some of us found that ours cars were delivered with a higher pressure intended to prevent flat spots during their Pacific cruise. The sellers are supposed to lower it to spec during dealer prep, but didn't do so. While not a problem for those of us who want higher pressure in our skinnier tires, it could unnecessarily harshen the ride for customers in your situation.

 

Since forged wheels are stronger, they are often designed with less material in them, which makes them lighter than a comparable design in cast aluminum. So even if they appear to be the same as a cast wheel, they may in fact have less material in the actual spokes and rim.