Poor steering and handling on the highway.

I like doing loopings with my Prius best! Or those good old barrel rolls!

 

No news because it was raining like crazy here that day, after 181 days without rain. So we've rescheduled for next month, the 19th.

 

This has been suggested previously on the Yahoo group...that we're making our cars wander. I have really tried the light touch at all times. But I've also done some experimenting, where I don't touch at all, but keep my hands just close to the wheel. Once there's some outside force like a cross wind, passing truck or van, or wavy grooves, etc. The car immediatly drifts to the side it's pushed to.

Then the needed correction causes that side of the car to slightly dip in the front, followed by yet another correction or two to keep it in the lane. If you're on a poor road, concrete usually, expansion joints, grooves, etc.., you need to continually do this sort of correction. It may subside somewhat if the road is suddenly smooth or the side wind dies. So if you're right next to temporary cement rail and a truck on the other side, there isn't much room for error. If the lane in somewhat narrow, expansion joint under the tire, you better not over or under correct too much or you hit something. It keeps you awake but very tired at times.

 

First a question then an observation:

Has anyone with an '05 experienced this problem? Before my Prius I had a VW Jetta, and I must say my '05 handles just as solid. I have never noticed the slightest bit of wandering, even when next to large trucks/busses.

I also used to have a small truck that I once had new wheels and tires put on. I used to drive it to work on the same stretch of highway. I immediately noticed random drifting on this highway after driving on it with the new tires. Felt exactly as you are describing! I also realized that it was only happening on the certain stretches of highway that have parallel grooves. After many alignment checks and head scratching I had an epiphany that the tread gap in these new tires might be very close in width to the grooves on the highway. The drifting got so fustrating that I finally pulled off to the side of the highway one day and measured the grooves on the highway. They were exactly the same width. My tires were slipping in and out of these grooves!

I'm willing to bet the Prius issue has something to do with specific tread patterns on a certain production run of tires. This combined with driving in areas where there are grooved highways could result in the random low percentage of people that are experiencing this problem. Thoughts?

 

Well, having just driven from MA to TX...

There were definitely times I noticed 'wandering'. Particular road surfaces seem to be something to do with it. Some states it would be worse than others. I put it down to bad road, as the car handled fine on most highway. It's certainly not a problem here in Austin; I've stopped thinking about lane wobble at 60-65 mph.

I also definitely noticed the car being pushed sideways by wind and by truck turbulence. Specifically, if a truck passes on the left going 70mph+, the car will nudge right as the front of the truck passes, and then get sucked left as the back of the truck passes.

Personally, I think the "truck suck" is only to be expected, given that the Prius is specifically engineered for light weight to boost fuel economy. It's something everyone was taught to be aware of in driver's ed, right? Maybe the people complaining are used to driving SUVs...

 

The one thing about the handling that I miss with the Prius is the loss of tactile feedback in slippery conditions, Unfortunately, we got an '04 pkg 3 so it also lacks the VSC option. I think that the VSC Could compensate somewhat for the lack of feedback from the steer by wire system. At least something would be paying attention to the feel of the road. Didn't recognize this issue until I was driving over Snoqualmie Pass the other day.

 

My recent experiences regarding Prii steering on a long road trip:

Driving our 10 day old 2005 AM on a vacation to San Diego in Mid October, my wife and I left Sacramento on a calm morning. I paid special attention to the car’s handling during the whole trip . . . worried about what I had read on PriusChat about cross winds. Interstate 5 through the central valley of California is noted for being flat, straight and boring for long stretches. I played a game of how far can I go without touching the steering wheel . . . 2.3 miles!!! I soon figured out that less driver input is better with this car. I also experimented by driving through 18-wheeler truck bow wakes several times with my hands completely off the wheel. Most of the time I noticed minor buffeting and was tracking straight coming out the other end.

San Diego. What the hell is up with your freeways!!! In some areas the roadway is grooved so heavily that I’m sure other drivers thought I was drunk! Especially bad is westbound I-8 coming down the hill from San Diego State University. Reason for trip was to visit a homesick freshman niece at SDSU, so unfortunately we did that drive several times - each one was a two hands on the wheel experience!

The drive home up the Pacific Coast Highway (1 and 101): Many twisty turns, heavy cross winds, extremely heavy rain storms and way too many Starbucks outlets (in some areas every half mile or so . . . a pet peeve of mine as I was really jonesing for some good coffee and that corporate gargantuan lays waste to large tracks of good coffee roasters).

I observed the VSC light twice - but no seat of the pants feeling of car losing traction. I guess I should have driven slower through the water puddles and mud flows, but the car felt in control of the situation no mater what mother nature or I threw at it. I did all of the driving as I felt relaxed and not haggard by the long drives. I was very impressed . . . except for San Diego’s freeways!!!

P.S. Got 50.5 MPG . . . and a parking ticket in Downtown Los Angeles at a city meter. I guess they don’t know what an exempt Hybrid Prius looks like!

 

At 2900 lbs or so, the Prius is the heaviest car I've ever owned. Heavier than the CRX-SI, Acura Integra, Acura RSX, and 93' RX-7. And they all were much less affected by wind and road grooves. And the CRX-SI, at only about 2050 lbs proves that a light car can "track". At about 2700 lbs, both the RSX and the RX-7, especially the RX-7, were the absolute best tracking cars I've ever owned or driven. It's a lot more than vehicle weight that affects the handling of a car. Center of gravity, weight distribution, side cross-sectional area, vehicle height/width/wheelbase/etc., suspension resistance to roll/sway/movement, tires, caster, toe-in, PS gain/assist, and probably so many other things can affect how a car responds to outside forces (side forces especially) when traveling at 60+ mph.

 

Hi Folks,

Just my 2 cents from Reno. I complained about the light handling and wandering when I first purchase the Prius. 8K miles later everything works just find for me and for my style of driving (I'm in no hurry to get there....).

I don't know if the car and tires have broken in or if I have adapted to the Prius.

I noticed the other day that I was not experiencing what had earlier seemed like a problem. The input needs of the Prius still seem very light; I’m just not having any problems driving it (or with wandering). The Prius is very susceptible to side winds and I drive through a very windy valley almost every day. Perhaps this has made me less sensitive…

 

TCD you have adapted.

when i got my Prius, i thought the body sway was a bit high and the steering too sensitive.

now i cant say that i have any complaints about how the car handles. i would have to assume that i am now simply used to it.

another thing to consider is that the low Cd of the car will contribute to its handling problems as the weight of ANY car isnt sufficient to hold it to the road.

that is why performance cars have spoilers. the spoilers are not for looks. they are wings that work just like an airplane wing except in reverse. they create downward force to make the car effectively heavier.

if you choose to believe a video game (a very realistic one modeled from the real laws of physics) a typical wing on a NASCAR can exert upto 1200 lbs of downward force at 180 mph.

the downward force is necessary to be able to negotiate low banked turns at high speed. the greater the downward force, the tighter the turn you can make at a given speed.

now all this is waaay beyond what we are concerned with right??

well maybe... then maybe not. your Prius has a spoiler on it and i dont think its for looks. could be... but it will help provide stability that can be noticed in turns. i dont know the weight ratio of the car but considering the position of the rear axle, the weight in he back has to be pretty light.

 

Dave, I think the weight distribution is 60/40.

Patrick. Thanks for the confirmation about our freeways in San Diego. Rt 15 is even worse than 8 and the almost constant west wind on this North-south freeway makes it worse. Seems they made the lanes one width and now they feel that they can be narrower and that way get an extra lane in. But of course that puts the expansion joints that were between the lanes right under your left wheel at times. All of these things make the average handling Prius bad at times.

Don't be offended by the word average. Let's face it, there are much, much better handling cars out there and none of them get 50 mpg of course. Our RSX gets maybe 25-26 but it tracks very well even with the bad roads. I just think that maybe Toyota could have done a bit better, such as with the European version, so that bad roads, winds, passing trucks, etc were not such a big deal. Don't Americans like handling too?

I'm really torn because I love almost everything else about the car except for the handling and, at least with my car, the dash sqeaks. The dealer fixes one sqeak and then another appears...or a rattle happens in another area of the dash. I'm getting tired of taking my car in to the dealer. For me it's about doing the right thing and driving a clean running, super economical car. But my Prius makes it difficult to do the right thing. It's one of those love/hate cars like my RX-7 was, lol.

 

OR, it could be to break the airflow so it doesn't exit poorly from the squarish back end - it lowers the coefficient of drag (cd). I don't think we are driving nearly fast enough for a rear spoiler to force the tail end down.

 

You can use the word boring for that stretch without resorting to BOLD and large font</span> with <span style=\'color:blue\'>color? What willpower!

It is interesting that the only place you note a horrible ride is in Fred's neighborhood. I wonder how many owners of other types of vehicles with similar characteristics (size, weight, tires, etc) have problems similar to Fred's.

I notice the "truck suck" thing, but it was worse in my Odyssey so I guess I traded the right direction. More power, less body lean, less truck suck, etc. It might be a tougher transition for someone used to a sports car.

 

I bought my Prius last week and have driven almost 500 miles and yes, I have felt the steering "have a mind of its own" when braking. It tends to wonder a little bit, but it's not a major problem so far. As far as the alignment, yes, I have noticed that after driving those 500 miles, the position of my steering wheel as changed and I haven't hit any major bumps in the road, so I am giong to take my vehicle back to the dealership and have them check the alignment. My thought about the steering, however, is if it was right when I bought it and wrong after the 500 miles, is the alignment that sensitive and will I always have to worry about having to go in for alignments all the time? As far as the crosswinds, I did feel the car sway a little bit when passing trucks, etc, but then again, my corolla and tercel used to do that a lot, but my RAV4 didn't have that problem. I better stop while I am ahead because I am starting to feel discouraged with my purchase. I'll hope and pray it is a minor problem. Thanks for all your feedback about steering.....

 

I returned to my dealer today to have the car aligned to my specs, 1/8th inch toe-in. Toe is more important to tracking accuracy than camber. I expected better performance from the new tires, and suspected alignment. Sure enough, toe before alignment measured 1/8th toe-out on the left, zero on the right, camber was to factory spec. Now that toe is to my spec, tracking is what I expected and found with my '04 after it was aligned to the same spec, straight and true.

This is the opposite setting to what I use for track and autocross on my race car that I want to rotate. It's set to 1/8th toe-out so it will change direction from sunspot activity.

 

Yes you're right about the camber. Even when I got the left and right to be the same at -0.5 deg I saw no improvement and didn't expect any either. I've got 0.03" and 0.04" left and right toe-in now and 0.08" or (0.2 deg) is the max of the tolerance. So you're running a little bit over at 0.125" My last alignment shop set it at 0.0" and 0.08" left and right. It will be interesting to see if you experience some loss in gas mileage or extra tire wear over time. Maybe that's what the Prius needs to track better but it does seem like a lot. Keep us posted on long term results.

 

I didn't notice any unusual wear pattern on my last '04, but I only kept it 4,000 miles. Mileage took a 20% hit when I installed Potenza RE-950's on it, although I had the alignment done at the same time. I didn't notice any mpg change today post-alignment (after zeroing the display) over the same roads as yesterday, my test loop on I-84 in the gusty Columbia River Gorge.

It's true the car is now out of factory spec. My dealer complied, but made me sign a CYA waiver like last time. It helped the wandering I experienced after the new tires were mounted yesterday. It's better, but The Gorge is extreme with winds 25 gusting 45, and combined with a flexy sidewall non-performance rated tire, I consider it acceptable. I miss the extra stability and ultimate grip of the Potenzas, though I'm still playing with tire pressures on the TripleTreds.

 

I had the 195H60X15 Hydroedge tires for about a month and really didn't notice much difference in gas mileage. I would have seen a 20% drop, but I did think they reduced around town gains that used to come easily once the car was warmed up. I didn't get the Potenzas because of your comments. I wish I had kept the 195H60X15 size now. What I did notice is that at pressures approaching 40-42, they would chirp or squeal if pushed only moderately on corners. The lower pressure seems to give more grip with the Micheliins.

I'm thinking about talking to the Evans tire shop and maybe buying their lifetime alignment with the idea of getting them to increase the toe-in by maybe 0.02" every month or so until I see some improvement. I just don't know what else to do because I think I'm just going to get the "it's normal" from the Toyota rep next week. And I'm starting a new job on Monday so I don't really want to have to take time off to hear that again from them.

I keep looking for new struts/springs/anti-sway bars but there's not likely to be anything available for some time, if ever. Anyone that's driven a car with a moderately firm suspension would recognize that the Prius is just a bit soft with lots of body roll, especially when correcting it on the freeway when it wants to wander. I really think this car could be made to behave much better on the roads here with a few tweaks...but at what cost? I wonder if I find someone to design beefier anit-sway bars, could I recoup the investment by selling to others that want some improvement? God I love (hate) this car!!!!

 

Congrats on your new job!

Yeah, if only we got the Prius GT or EU spec car here, most of these complaints would be resolved, I think. Maybe someone here from there could send you a set of sway bars to test?

I'm trying 40ff/37rr today. I'd like to eliminate the one extra oscillation coming from the rear during a simulated slalom exercise. It's something the Potenzas cured on my '04. I don't think the ride quality on these TripleTreds will be affected much by more air. I'll listen for slip through my imaginary slalom course and adjust down from there.

 

Fred, did you have that meeting with the Toyota rep on the 19th?