Low Rolling Resistance Tires...Which is Best?

I got the Bridgestone Ecopia EP422s recently, took a chance since they were brand new and didn't really see any reviews on them. I like them, they were decently priced and the ride isn't bad. Unfortunately I had just bought the car before putting them on so I don't have much to compare them to, but for ride quality they're pretty good and haven't had any problems in rain. I'm actually going to increase the tire pressure soon to see how it affects my MPG now that I've established a fairly decent baseline.

I had run 70k+ miles on my Michelin Energy MXV4+s in 195/65/15's and really liked them. I wanted to go to a larger diameter tire 205/70-or-75/15. I put a set of 205/75/15's on and drove them for a little while (10 miles or so). They cleared everything but it was a close fit and they looked out of place and drove poorly.

So I tried a set of Yokohama Avid Touring 205/70/15's

They rode/drove nice, I liked the RPM reduction (~6%), it made my speedometer ~accurate (half a needle width slow). My initial reaction was that they didn't roll as nicely/smoothly/etc. After driving them more and more on my same daily route I just wasn't able to coast the same distance at the same speeds that I was able to with my Michelins. I drove them for ~10k miles and one of them broke a belt.

I replaced both front ones with General Altimax RT's also in 205/70/15's. I noticed a difference in rolling resistance right away. After a couple thousand miles I also replaced the back ones with the same thing. I don't have any hard data but they definately roll at least as well as the Michelins. I can coast approximately the same distance as I could before at the same speeds.

For any normal driving the taller tire is nice. Combined with the 0.681 5th gear it's about 30 RPM/MPH so 1800RPM @ 60MPH, 2100RPM @ 70MPH, etc. If you do any trailer pulling you'll definately notice the lower RPM's as you are definately on the negative side of the torque curve. It will still pull it, but it works much harder and the cruise control really works to maintain speed with the trailer on rolling hills.

We'll see how the General's wear - they've been good so far for MPG's (mid 50's with no effort).

Hope this helps someone make a decision.

Has anyone tried these out? I think they are a new product from Kumho...

http://www.tirerack.com/tires/tires.jsp?tireMake=Kumho&tireModel=ecowing+All+Season+KH30

or these??

http://www.tirerack.com/tires/tires.jsp?tireMake=Kumho&tireModel=eco+Solus+HM+KR22

tadc said:

I changed from Stock Contis to Michelin Energy and noticed a 2-4 MPG drop. Disappointing.

Click to expand...

ALL tire manufactures will tell you... Old tires will always get better mpg than new!!

Let me repeat.

OLD tires get better mpg than new tires..


Old tires get better mpg than new tires.

New tires are stiff and the cords have not loosened up yet.

SoTxBill said:

Old tires get better mpg than new tires.

New tires are stiff and the cords have not loosened up yet.

Click to expand...

I have heard this MPG difference attributed to the flexing of the tread blocks, and that worn tires have a smaller diameter, causing the odo to read more miles completed per tank than "new" tires.

New tires have a bigger diameter, will rev less per mile, and thus will "show" less mpg than the worn tires you just removed.

To determine the difs, let the new tires break in for 500 miles, then factor in the differences in tread depth between old and new tires when interpreting your mileage.

Ray

GPS vs. odometer

raybo said:

New tires have a bigger diameter, will rev less per mile, and thus will "show" less mpg than the worn tires you just removed.

To determine the difs, let the new tires break in for 500 miles, then factor in the differences in tread depth between old and new tires when interpreting your mileage.

Ray

Click to expand...

Will using a GPS get me more accurate miles driven per tank on a new tire (after the ~500 mile break in period) for MPG estimation purposes?

I just replaced my OEM Michelin MXV4's at 40k miles. There was plenty of tread left, but the sidewalls were showing cracks. I've never seen this in tires less than 5 years old, and my TDi doesn't even spend much time in the sun.

I replaced them with Conti ProContact EcoPlus (supposedly a LLR tire). They don't chirp on a fast start like the Michelins, seem to have really good dry grip. I've noticed no difference in mpg's.

Heck- just get the tires that work the best for your purposes. Tried some "fuel-saving" Michelin X 'Green' tires on my 04 Golf. Most expensive (115$) and worst tires I have ever experienced. Horrible ride even at 40 psi, no noticable improvement in MPG, and the only tires I have ever seen that hydroplane - in the dry! I drive assertively but not aggresively in the wet and those were like driving on pizza plates. Gave them to Goodwill after 20000 miles. Put on some Bridgestone RE960's that are quieter, give much better steering response, stick better under all conditions and cut through heavy rain like a knife. Just over 30k on them now and perhaps half worn with pressure at 44. Very impressive at 75$ each.

obscure

how can you tell if you just gained or lost 1.5 mpg. there are so many variables while driving that it would be impossible to tell. air temp, red lights, heavy traffic or maybe extra passengers in the vehicle. just get the best tire you can for your money. your life rides on it

Jon Linn said:

Has anyone tried these out? I think they are a new product from Kumho...

http://www.tirerack.com/tires/tires.jsp?tireMake=Kumho&tireModel=ecowing+All+Season+KH30

or these??

http://www.tirerack.com/tires/tires.jsp?tireMake=Kumho&tireModel=eco+Solus+HM+KR22

Click to expand...

I have 6K mi. on the ecowing KH30s. 185/65H-14. Quiet, smooth-riding. No balancing/runout issues. FE went up 4%, but comparison is dicey because they replaced well-worn Yokahama Avid T4s in a 205/50T-15. If they prove to be reasonably durable and even-wearing, they would provide good value and probably warrant consideration.

Just got Yoka Avid Envigors from Tirerack. Supposed to be good rain tires. They're quiet, don't know how RR can be determined.

I am using the eco Solus KR22's on my 2005 Beetle with good results so far.

My 2011 JSW has Michelin Energy MXV4 S8 oddly enough.

They are $142 a piece, versus $112 a piece for Continental ExtremeContact DW tires. That is $120 a set....

Is it actually beneficial to purchase the LRR tires?

Yes, but only once the originals have worn. If you replace a good set of tyres you'd just be wasting money.

Of course since your fuel is so cheap (relatively) the payback will be slower for you than it is for us.

LRR - Best Advise

Don't waste your time.
I get rid of my 160lb Girl Friend, and noticed a 1.2mpg increase this last year.

However, last yr's winter was mild, and she was great in pushing me out of drifts, so I'm considering reconcilliation at this point, and she was good for the ride,though she has lost 30lbs.

Replacing my faulty turbo actuator and getting Michelin Defender XT tires is the difference between me getting 41 mpg and 45 mpg consistently. Adding in some hypermiling got me to 51 mpg on a tank doing just my in-town commute. I would like to see what I can get on a long-trip, now.

I had mine installed at Sam's Club, where they were (and are, again) offering an instant savings about $70-80. They usually run this and a Goodyear offer.... you can usually get one, of not either, of these all of the time.

I rode in a tdi with Michelin Hydroedge tires and they sounded like big lug mud tires. The road noise!!!! Holy crap!!!! I won't be buying those.

gilberjj said:

I rode in a tdi with Michelin Hydroedge tires and they sounded like big lug mud tires. The road noise!!!! Holy crap!!!! I won't be buying those.

Click to expand...

I don't think you will, because I don't think they've made them for some time. They were replaced, more or less, by Defenders.

Talk about bringing a thread back from the dead!! It started back when 90K tires were shipped for $55 each, and ended 2.5 years ago. Until yesterday, that is...

A slight drop in rpm at cruising speed is good for some additional mileage, as long as the tire isn't lots heavier.

I have stock 16" wheels on my 2014 JSW. I am considering a ~0.7" diameter increase, and 2 pound per tire increase in weight from OEM with the following Conti:
PURECONTACT WITH ECOPLUS
205/60R16 91H
91 is the lower weight limit (~1300 pounds instead of ~1500)
The H rating is 130 mpg, not 150mph. Same rating as OEM tire:

Stock tire is a 205/55R16 91H ContiPro Contact

It will drop the revolutions per mile from 837 to 808

That's just a 3.5% drop in rpm at ANY speed. There's certainly enough torque to handle this under most situations.. It is a subtle change.

Any thoughts?? I've done this before (Passat) with a modest gain in FE, but that was a slightly stronger engine (2013 NMS TDI).

ONE other thing... wear rating of the Pro is 400, and for the EcoPlus Pure Conact it's 700. Traction is rated identical.