jbripps

Hi all,

I've had my car for about 9 months, came with original Toyos. Well, with winter arriving, I wanted to put new shoes on since the Toyos are terrible in the snow. I had 34k on the clock, but not much meat left.

I just purchased BridgestoneŽ POTENZA RE970AS 225/45R18 all around. This is the same size as what I replaced.

They grip great, and are suppose to be pretty decent in the snow, BUT, I notice that the car feels MUCH heavier and is takes much more "energy" to keep the car going in the all electric/under 42mph mode. The engine just needs to work harder to accelerate.

Also, I am getting 5-6, maybe 7 MPG less (ALWAYS get 35-38, now I'm averaging 30, ughh!).. Is this common on a tire swap? The car used to "glide" much better, now feels like I have 100 bags of sand in the back..

Any input/feedback would be greatly appreciated.

Thanks!
Jon

jbripps

Hi all,

I have the HS250H, but there is a lot more traffic over here, so I thought I'd discuss my issue here. I've had my car for about 9 months, came with original Toyos. Well, with winter arriving, I wanted to put new shoes on since the Toyos are terrible in the snow. I had 34k on the clock, but not much meat left.

I just purchased BridgestoneŽ POTENZA RE970AS 225/45R18 all around. This is the same size as what I replaced.

They grip great, and are suppose to be pretty decent in the snow, BUT, I notice that the car feels MUCH heavier and is takes much more "energy" to keep the car going in the all electric/under 42mph mode. The engine just needs to work harder to accelerate.

Also, I am getting 5-6, maybe 7 MPG less (ALWAYS get 35-38, now I'm averaging 30, ughh!).. Is this common on a tire swap? The car used to "glide" much better, now feels like I have 100 bags of sand in the back..

Any input/feedback would be greatly appreciated.

Thanks!
Jon

Mitch08ISF

iTrader: (8)

Yes my set up will only allow for 40+ mpg if I'm on highway 90% of the time. So yes messing with rolling resistance dramatically decreases the mpg. I say stick with oem unless you get a wheel that weights 12-15lbs each. The look I have is great but its costing me money.

RTIS250

iTrader: (9)

It isnt always the weight of the tire... OEM tires are low rolling resistance design, rather than high performance.

m R g S r

I'm betting its due more to the cold air / higher butane content in the fuel here in the NY winter.

My mileage has dropped since summer. Same tires.

Also, having the heater on causes the engine to run more and not shut off as quickly.

All this plus the slightly higher rolling resistance of your new tires (softer cold weather compound) could equate to a drop in MPG.

DDS62

I would say your experience "pretty much" indicates why They put those tires on the HS in the first place. No traction, stiff ride, increased noise level and very short tire life but much better EPA mileage for the sales department. I have read accounts of owners replacing their 18" wheels and 45 series Tires with 16" wheels and 60 series grand touring tires in an attempt to achieve a better ride, while paying a penalty of 1 to 3 mpg. 7 mpg, or about a 20% penalty seems high, but in hind site I believe it, because few people ever tell the whole truth about mileage.

We have talked here several times about the Hybrid concept. A hybrid's efficiency is the sum of several systems that operate together around the new high efficiency low torque Atkinson cycle engines. Very little increased mileage is the result of the regenerative braking which basically only supplies the electricity to provide electric motor motor torque for intermittent acceleration. The other systems that add a significant amount of mileage is the greatly reduced engine and rolling drag (which you have noticed) and the visual power and mileage feedback that are available real time to the driver via the computer systems. Ironically all of theses systems can be incorporated in any car and will preform as well. Ford is selling a car in Europe (I think) that incorporates a high efficiency diesel engine with the the other hybrid systems. I am just saying that your experience illustrates how significant the "reduced drag trick" plays in the hybrid system.

Appreciate the better traction, you really need it anyway, and get another set of Toyos in the spring.

FLYCT

When I replaced the OEM low rolling resistance tires with standard Michelins on my Prius I lost about 5% in gas mileage.

JR

mitsuguy

iTrader: (2)

Those RE970's are amazing tires, would put them up against any tire in the category for wet weather, dry weather and even light snow traction...

that being said, they are a relatively heavy, very planted tire - they need to be to put up with the type of abuse people generally give them and they can definitely take it... Rolling resistance for fuel economy was absolutely of minimal concern when Bridgestone designed that tire...

All of that being said, 7 MPG is pretty significant and it should get better as the tire wears... A worn tire will almost always get better gas mileage than a new tire - there is less tread to squirm so less mechanical losses...

TheAirman

Yes they are great tires. They stick like glue. But basically he bought tires that were made for the LFA, and put them on a 2.4 liter hybrid.

Really a good tire but a bad choice for a hybrid. And like DDS62 posted, if you want to keep the "hybrid model", you got to shop for LRR tires first and performance last.

But don't worry, with a tread wear index of 400 for the RE970's, I'd guess he'll be shopping for new tires in about 8000 miles, if my experience with those type of tires holds true.

jbripps

wow! thanks so much for the replies! Yes, they are great tires, with a 40k warranty, so I'm not sure what to do. I really do want my fuel efficiency back. I got over 30k miles on my toyos, and didn't think the ride was that terrible.

After researching, it does appear that I need low rolling resistance tires. I just put these on, so I will call costco and see what they can do, their customer service is outstanding. My MPG drop is directly related to the newer tire, temps have been the same here. It's amazing how drastic the change is.

With that, other than the original Toyos, can anyone suggest other LRR tires to consider?

Thanks again,
Jon

Magellan55

Keep in mind you'll see a small drop in indicated mpg just putting on new tires - they have about 5mm of extra tread (= bigger radius, more distance traveled per rev) compared to a worn out tire - equates to ~1 mpg indicated for an HS.

I swapped mine out for Conti DWS's, and saw several mpg drop as well (not 7 - more like 3-4). But my wet grip is so much better it's worth it - those Toyo's were like plastic.

jbripps

Magellen - Thanks for the unput. I have since pulled those tires and replaced them with Michellin Primacy MXM4's. They were cheaper, and are fantastic. I have driven in the rain and snow and have zero complaints. AND, they roll ten times better than the Bridgestones.

I'm still lower, but it's been super cold here. I'm down about 4 MPG, which seems normal under all of the circumstances. Interested to see how these do when the weather breaks and I'm at 10k on them.

And yes, the Toyos were a joke, especially in the rain. Overpriced POS in my opinion.

Here's the tire I grabbed. Haven't seen anyone mention them previously on this board.

http://www.tirerack.com/tires/tires....l=Primacy+MXM4

Best,
Jon

ceads9

Let me us know how it goes. I have Same tires ,but haven't put them on yet. I'm milking them to get a few more miles . Let us know about the ride . Mine is a loaded 10 with 25k

Chris

Magellan55

Yes, let us know how you like the MXM4's. I was torn between those and the Conti DWS that I eventually bought (cheaper). My all-time favorite touring tire is the MXV4, tho it doesn't come in the 18" (they fit the 17" HS wheel). IMO it's a great blend of wet handling, ride, noise, mpg, longevity, and near-the-limit good behavior. I heard differing opinions about whether the MXM4 behaved like a lower-profile MXV4 or not.

ceads9

Just put on my new michelins MXM4 only had 25 k on the toyos , still have life left in them. I wanted to get them broke in due to another trip from Kansas to Destin in July. Spent the week driving to Kansas City and Pittsburg, KS. Around 300 miles. First off the ride is better and very quite . Can't tell about mpg yet. Drove in 30 degree weather with 20 mph winds (side and front) car said 30.5 . Usually we get 34-35 when we do these trips with good weather, so not bad. I can tell you they are a better tire so far . I noticed it as soon as I drove the car. I also have the energy s on my Prius and these seem better on the seat of the pants feel.
Chris