Tire Upgrade

Tire Upgrade and odometer/Speedometer calibration

I upgraded my original Integritiy's with the Goodyear Assuarance TripleTred 195/60R 15's and after make a long drive in the rain and light snow I am already a believer. Glued to the road rather that feeling unsure as before.

My question is I seem to be off about 2% in odometer calibration. The Odometer is reading 102 miles for every 100 actually driven. Likewise the Speedometer is reading about 2 mph faster at highway speeds than actual speed. i.e. 67 mph vs 65 mph actual.

Is there any type of setting or calibration that can adjust to the 195 tire size from the 185 for accurate readings?

Thanks!

 

longbow,

I don't think there's anything you can do about adjusting the calibration of the odometer to account for the different size tire.

Your different size tire should result in a 0.9% over-read compared to the OEM tire size.

One of these days when I'm on a long drive on an interstate with milege markers on the side of the road, I'm going to check my odometer reading against the milege markers.

 

We have a 5 mile stretch of road that has the one mile markers to check your accuracy. I had .2 more on the odometer than the 5 mile mark so 4% higher odometer readings or 4 miles more per hundred. I plan on running this baby into the ground so I am not concerned about the extra odometer reading. I just figured if there was a way to adjust it would be handy.

 

I thought our odometer only gives whole numbers?

Anyways, almost all of your odometer over-read is due to Toyota's factory setting of the odometer and not your new tire size.

There are international rules for factory odometer settings posted somewhere here on PriusChat. The two bottom line rules I remember are (1) manufacturers are prohibitted from setting odometers to under-read, and (2) manufacturers are allowed to set odometers to over-read by as much as 10%.

 

Aha! I did not have a chance to check this prior to the new tires.

I do know that the speedometer was affected. It generally reads 2 mph higher than before. Probably not a bad thing. I'll be going slower than it reads so less chance of my sporty red car being pulled over for speeding!

 

For what its worth, I think the standard equipment tires are great. But, since I use true snow tires in winter, does anyone have a suggestion for a good "summer" replacement tire. Something with decent treadwear and mileage? Not an all season tire since I use snows in winter.

 

here, check this out:
http://i2.photobucket.com/albums/y36/slkgitong/IMG_4152.png
http://i2.photobucket.com/albums/y36/slkgitong/IMG_4149.png
http://i2.photobucket.com/albums/y36/slkgitong/IMG_4147.png
http://i2.photobucket.com/albums/y36/slkgitong/IMG_4146.png
http://i2.photobucket.com/albums/y36/slkgitong/IMG_4145.png

 

Lee, et. al.-

Have you had a chance to actually change out the tires on your Touring baby?

I'm looking to replace the stock tires after 30K and wear bars showing. :\

I was hoping Costco would carry some nice ones, but the ones that they have in 195/55R16 are limited. (Only Michelin Pilot Primacy for their current sale)

When I fooled their system by entering my car as a 2007 Mercedes C280, I can look at the 205/55R16 tires and there are more options. But no Hydroedge.

So it was off to Tirerack.com...

Hydroedge is ok, but has mixed reviews there.
Pirelli P4 Four Season look nice
Michelin Pilot Exalto A/S are lower miles, but very highly rated. And they are available at Costco.

So, I'll get those and see how it goes.

 

Why are so many preferring 195/60-15 over a 195/65-15? The 65 seems to have a preferable Rev rating. Is there a big mileage difference? Are those who want a larger tire just moving up to the 205/60-15?
I need to replace the Integrities; I am looking for something that is good in wet weather, comfortable and quite.
I am favoring the HydroEdge at this point. Too many conflicting comments about the TT'S.
Thanks for your comments.

 

According to every tire size calculator I've tried, as a replacement for the OEM 185/65/15 tire, the 195/60/15 will have less speedo/odo error (1.0% over-read) than the 195/65/15 (2.1% under-read), e.g.:

Tire size calculator

And the RPMs published by TireRack.com (which should be based on the manufacturers' supplied info) show even less error between the OEM Integrity's 185/65/15 and the TT's 195/60/15. Here's the RPM info for the applicable Integrity, TT, and HE tire sizes:

Integrity 185/65/15: 855 RPMs

TripleTred 195/60/15: 863 RPMs
TripleTred 195/65/15: 836 RPMs

HydroEdge 195/60/15: 867 RPMs
HydroEdge 195/65/15: 842 RPMs

From what I've read, the HydroEdges are a great tire. But the TripleTreds test better according to road tests by Consumer Reports and TireRack.com, and are rated higher by TireRack.com's customers.
However, the HydroEdges do have a longer treadlife warranty (90k vs 80k).

I don't think you can go wrong with either the TTs or the HEs. But there's definitely less speedo/odo error with the 195/60/15 size.

BTW, I think you should expect to get a 2 mpg hit from going with the 195 mm tread width.

Good luck.

 

Touring Tire Replacement

I've read nothing but good things about the Michelin Pilot Exalto A/S.

Alternatively, I'd consider the Falken Ziex ze-912 tires as replacements for the Touring's Bridgestone Turenzas. They're cheap (about $75 each), come in the Touring OEM size of 195/55/16 (so little or no speedo error or mpg hit), and their predecessor or cousin -- the Ziex ze-512s -- are highly rated.

 

Better Tire for wet weather , quiet, hanling

Tom,
It looks like the closest RPM to the 185 is the 205/60-15 at +.9%. I wonder how the MPG works out since the 195-60 is -1%. I have to believe that the 195 is still better than the 205 but I would guess it is closer than it seems.
I really wanted to get a better ride and wet weather performance over the original Integ. They are worthless and I am probably overreacting but my guess would also be that the higher wall on the 65's would give a better ride. I have Pilot Sports on my Camaro and don't expect the Prius to give me the handling of the modified suspension on the Camaro but if was a little better than the original that works for me.
I will probably just stay with the 185'S and get a better tire.

Thanks
Tom :high5:

 

Hi Tom,

You might want to check out TireRack.com's latest road tests of 4 popular and generally well regarded Passenger All Season tires (Goodyear TripleTreds, Goodyear ComforTreds, Michelin HydroEdge, Michelin Harmony). Note that the ComforTreds, HydroEdge and Harmony come in the standard Prius OEM 185/65/15 tire size.

Comparing Our Top-Rated Passenger All-Season Tires

I have the TripleTreds in the 195/60/15 size. I love them (this is the third car I've put them on). But there are lots of good tires out there.

Good luck again.

 

I have a 2008 with factory installed P215/45ZR17 handles great and looks great with the 17in crome wheels , Im not sure about the mpg. only getting 42mpg city.

 

I've put 500+ miles now on the Falken Ziex ze-912 195/55-R16 tires. Very pleased so far (except for my TPMS light, but that's another story). Running 42 psi front, 40 rear. I've noticed no drop in mileage from the 185/65-R15 stock tires that were previously mounted. The Falken's are quiet and impart excellent road feel. I found no issues on wet roads.

All things considered, I'd buy them again in a heartbeat.

 

Just had to replace the tires on my 2007 Prius touring after an "incident" with a curb caused a sidewall tear on the stock Turanza EL400s.

I've always wanted to replace these tires, but the choices in 195/55-16 are limited and mostly consist of runflat tires for the Mini Cooper. While 205/55-16 remained a perfectly good alternative, the downside is that the stock 6" wide rims are a bit on the narow side for 205s. Still within tolerance, but hardly optimal. Here in southern California I have no weather issues to speak of, so there's been no real urgency to this. I figured I'd wait to see if anything better came along, but in this case my hand was forced.

Turned out to be OK though. Bridgestone has recently introduced the Potenza G019 Grid in 195/55-16. It's similar in many ways to directional all-season Potenzas (the old RE950s and the G009s) that I have used on other cars and really liked. Price was not awful either. Available for $92 on tire rack. I opted for a local dealer who I have had good experience with before. Probably paid an extra $10 per tire after allowing for shipping, installation and disposal of the old tires, but I got to work with a dealer who is really good, isn't going to screw up the TPMS sensors, and gives me free rotation and alignment checks every 5K miles once I've purchased from them.

The changeover gave me the opportunity to look over the stock tires carefully. To say that they're crappy would be an understatement. The sidewalls are extremely flimsy which probably explains how it tore so easily in a fairly routine curb encounter. The wear was also quite evident. I've got a little under 10K on the car and the front tires were already noticably worn. Probably would only go to 20K, or maybe 25K if I rotated them a bit more regularly and spread the wear around. I picked the best looking one and put it aside as a spare just in case I ever really need a tire RIGHT NOW and can't find anything in this slightly oddball size.

[The dealer pointed out that the Turanza EL400s in this size are a special OEM tire, that are most likely different from standard EL400s with which he has had decent experience. As noted in this link, Bridgestone doesn't even publish most specs for them. The dealer also noticed that this size differs from most EL400s in both wear rating -- extremely low at 260 -- and speed rating -- V rather than T or H. If you look at the spec sheets, it seems that Toyota does this same combo for a number of vehicles: Lower wear rating combined with a V speed rating on cars that really don't need it. There seem to be some odd tradeoffs going on in the world of Toyota OEM tires. I would have much prefered a better wear rating, a sturdier tire and a lower speed rating. After all, the Prius can only go 103mph, and as such doesn't even require a speed rating above "R"! I wonder if the Integrities on the standard Prius have the same issue?]

So far I've driven about 200 miles on the new tires and I'm very pleased. I'm currently running pressures at 5psi high, which is to say 40/38. This is the same as I was running on the stock Turanzas, but I think they may not handle (or need) the overpressure as much as the original tires which were overly squishy at the "normal" pressures, so adjustments will probably be made.

The first longish drive on these involved a trip through some of the Canyons north of Malibu to get to a business meeting then a 60-65mph drive back on southern California freeways with one big up/downhill along the way. For the drive up, I intentionally detoured onto some of the smaller, narrower and curvier roads. With these tires I was able to push through the curves without constantly slowing down. A huge change from the stock tires. The G019s hold the road wonderfully.

On smooth blacktop they are wonderfully silent. On concrete there is a bit more of a radial "hum" to them than with the stock Turanzas. The steering is far more sensitive and I get much better road feel. On city streets in LA you do feel the bumps. If you like squishy, maybe you'd consider them "harsh." Coming from Acuras and Audis I consider them pretty normal, but as noted I will probably play with pressures a bit to find the optimal "sweet spot" for my driving and my roads.

Mileage has not been all that different from before, maybe 1-2 mpg lower though I don't have much of a sample yet. For these 200 miles I've been about 50-51 on the highways and overall averaging about 46-47. As I said, a little low compared to what I've seen before but not by much. The changeover did coincide with a major heat wave so I've been running the AC full-time since the tires went on and that has probably had some impact on my overall efficiency. Obviously the tires are also not broken in yet. Going to monitor it over the next few weeks and will report back. I'm hopeful that after tire break-in, with the AC back to normal use levels, and after experimenting a bit with tire pressures, my efficiency won't be impacted much.

Looks are quite good. The G019s have a much straighter sidewall than the stock tires. They look quite good on the stock Touring wheels, which I use without the plastic wheel covers. It's a subtle but noticable difference and another reason I'm kind of happy I waited for a tire in 195 rather than 205, which I think would have made for a much more obvious "fat tire on narrow rim" look that I don't like.

One thing you snow-country folks should probably note is that I've never been crazy about any of the Potenzas on snow. While these are rated M+S, if they're anything like the G009s, they will be great wet/dry performers, which is all I really need in coastal California.

All-in-all, I'm quite happy with these. Will report as I have a few more miles on them and do a bit of pressure experimenting.

 

Just cross-posting here from a post I made in the recent thread on the main board about high mpg tires.
http://priuschat.com/forums/prius-m...tter-mileage-than-originals-3.html#post653159
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Quote:
Originally Posted by Ichiro
in any case, I think the Pirelli P3000's have very low rolling resistance too.

I don't think these are made any more, or at least they're not listed on Tire Rack. I did find the Pirelli P4 Four Season tires though and they seem to be a very good all season tire that likely have low rolling resistance. They feature a "silica-rich tread compound" and they get 855 rev/mile (same as OEM Integrity) for the 195/60/15 size or 851 rev/mile for the OEM size of 185/65/15. Anyone have any experience with these or can provide any comments. I'm about on the verge of buying a set in the next week or so.

My next choice might be the BF Goodrich Traction T/A T. I'd also appreciate any comments on these if anyone has experience with them. Here's a link to a side-by-side comparison of the two.
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This thread is a great resources and I think it's good to keep pertinent information here if possible instead of spread out in many different threads. Thanks nyprius for all the research and legwork you put into your search and sharing it here. I certainly appreciate it as I am now looking to upgrade.

I also looked into the Goodyear TT's and CT's as well as Michelin Protenza MXV4 and HydroEdge. What I'm finding is that you pay quite a bit more for those tires and they are rated only slightly higher (if at all) compared to the two I linked above. Also the Pirelli's have an 85K mile warranty and probably get slightly better MPGs than the others. They get slightly lower ratings in snow and ice compared to most of the others, but are still in the good to excellent range. Since they are surely a huge improvement in this category over the Integrity's (which I managed OK with this past winter), I'm not too concerned about that. Otherwise, I'm not really seeing the downside to them right now. But I'm all ears if anyone can tell me otherwise.

Here is the side-by-side comparison for all 6 of these tires in 195/60/15.

 

i have cooper weatheredge...or weather somethings on my 06 r/n. im thinking of replacing em with khumo solus kr21 185's

85k treadlife warranty for the price cant be beat...the only thing im really worried about is the fact that these are not lrr tires. but then again i bet the coopers arent either.

 

OK, I bit the bullet and put my order in on TireRack for a set of Pirelli P4 Four Season tires 195/60/15 (came to $308 shipping incl.). Should receive them early next week and have them mounted before we leave for vacation on the 3rd. I'll report back after my road trip about handling and mpg. I expect some loss in mpg particularly given new tires compared to my worn out Integrities. Also going up a size in width probably won't help either. However I'm hoping (perhaps naively) that the silica compound might reduce rolling resistance enough to keep it close to what I was getting before. Same revs/mile as the Intregties (855), so I should be good as far as mileage calculations are concerned.