[toddrynewt]

Hi all... posting a pic with this of my 06 CRV with "real time AWD". The plan is to use this for canoe/camping trips, without any serious off-roading duties. But there are steep muddy put ins and take outs from time to time. I figured this would be a good vehicle to offset the costs of taking my pickup for camping trips and as a daily driver.

I put some 17 inch wheels that I got cheap from an aftermarket dealer paired with 225 65 R17 cooper CS5 touring tires. Circumference difference went from 84.82 to 89.6 inches. Love the ride as well as the look, and the cornering/handling compromise doesn't bother me. Unfortunately I didn't calculate gas mileage before the wheel/tire switch. But, I'm getting 17 mpg average in city and highway conditions now. Mostly city miles but still... WTH?! I can drive my old 5.4 L V8 Silverado and do about that well. Was the shitty gas mileage created by adding larger wheels/tires? Or do I have something seriously wrong with fuel consumption? Any thoughts or ideas for diagnosing the cause appreciated.

 

[rocky]

Increase in unsprung weight is one reason for worse acceleration and braking
Change in overall diameter will change the gearing if the V as well.

 

[racoon]

Your engine is working harder to spin those larger wheels and tires.

 

[williamsji]

Hi all... posting a pic with this of my 06 CRV with "real time AWD". The plan is to use this for canoe/camping trips, without any serious off-roading duties. But there are steep muddy put ins and take outs from time to time. I figured this would be a good vehicle to offset the costs of taking my pickup for camping trips and as a daily driver.

I put some 17 inch wheels that I got cheap from an aftermarket dealer paired with 225 65 R17 cooper CS5 touring tires. Circumference difference went from 84.82 to 89.6 inches. Love the ride as well as the look, and the cornering/handling compromise doesn't bother me. Unfortunately I didn't calculate gas mileage before the wheel/tire switch. But, I'm getting 17 mpg average in city and highway conditions now. Mostly city miles but still... WTH?! I can drive my old 5.4 L V8 Silverado and do about that well. Was the shitty gas mileage created by adding larger wheels/tires? Or do I have something seriously wrong with fuel consumption? Any thoughts or ideas for diagnosing the cause appreciated.

Since you did not calculate or establish fuel mileage before the tire change, you are basically "driving blind" here with this complaint.

You went with a one inch larger wheel, yet the same 225 65 Rxx tire profile, so I really don't see the wheel change being your issue here. It's a vey modest change.

The gen2 CRV, which your 2006 is, was rated new as 22/27 for an AWD. You stated that you did mostly city driving in your 17mpg result and honestly.. that is NOT a bad result for a gen2 CRV for city driving. I had a gen3 that I drove almost exclusively in town stop and go short trip driving... and it was rated 20/27 and in point of fact.. my average mpg on that vehicle over time was just under 15 mpg. So.. honestly.. your results sound about right from my experience as CRVs do tend to get close to rated mpg for highway, but do not in most cases get very close to rated city mpg. There are a lot of reasons for this, and one of them very much includes how heavy your foot is coming off of an intersection after a stop. Add to that the number of poorly syncronized lights in your community (my community is attrocious for this) and you are simply not going to see the rated 22 for the gen2... in my view. The number of passengers, as well as cargo also takes a toll on your mpg in a small SUV like this.

Also note that the older 2.4L engines in the CRVs are real workhorses, but are NOT small 4 cylinder engines by any means.

 

[Carbuff2]

note that the older 2.4L engines in the CRVs are real workhorses, but are NOT small 4 cylinder engines by any means.

Still, even these larger 2.4L engines develop their highest torque at higher engine speeds. So it would be difficult for the engine to 'get the car going' at the same rate as you were used to, with the heavier wheels & tires, without significantly mashing the GO pedal..

By any chance have you compared the weight of the old wheel/tire assembly with the new ones?

++++++++++++++++

Otherwise I agree with @williamsji . They shouldn't make THAT much MPG difference. (Still, they look sharp every time you stop for gasoline, LOL)

 

[crv383]

Ever ride a 10 speed bike? Is it easier to get rolling and stay rolling in say 3rd gear vs 6th gear? The taller tires have the same affect.......a little more push is needed on the go pedal to get the increased diameter turning.

This doesn’t take into account the motor having to turn both heavier wheels and heavier tires.

My 5.3L GMC Canyon got 12 in town and 18 on the highway, cruise set.

Buy a vacuum gauge and keep the needle above 15........you’ll get better mpg.

 

[toddrynewt]

Thanks for posts all! Yeah, the issue of tire circumference increase = workload increase on the motor was pretty much the crux of my question. I just hadn't thought it would affect the mgp that much. Some disagreement in the responses on that one. Definitely should have calculated my baseline mpg before the wheel/tire switch . So I'll never know. I'm still surprised by it. One thing I didn't calculate though is that since the circumference is increased and the odometer/speedometer is calibrated to smaller setup... My mileage isn't quite as bad as I'm calculating. As long as I don't run that math either, I can just feel a little better and leave it at that. ? Still a nice little ride and fun daily driver. Thanks for the replies! Now to put some monster roof racks for the canoes and increase my drag a little bit more! hehe

 

[crv383]

What?.......no vacuum gauge?

 

[williamsji]

Thanks for posts all! Yeah, the issue of tire circumference increase = workload increase on the motor was pretty much the crux of my question. I just hadn't thought it would affect the mgp that much. Some disagreement in the responses on that one. Definitely should have calculated my baseline mpg before the wheel/tire switch . So I'll never know. I'm still surprised by it. One thing I didn't calculate though is that since the circumference is increased and the odometer/speedometer is calibrated to smaller setup... My mileage isn't quite as bad as I'm calculating. As long as I don't run that math either, I can just feel a little better and leave it at that. ? Still a nice little ride and fun daily driver. Thanks for the replies! Now to put some monster roof racks for the canoes and increase my drag a little bit more! hehe

Based on the measured circumfurence you presented above.... the difference is ~5%. I doubt that would be notable in terms of load on the power train... and in terms of mpg based on wheel-2-road distance... you are looking at around a 1mpg difference... favoring the larger tire in terms of final mpg.

So.. my conclusion is that based on your reported driving and driving conditions..... as I noted in my earlier post, 17 mpg is about right for a gen2 CRV in proper working order and the 2.4L engine. Keep in mind... in the earlier generations of CRV (prior to Honda putting CVTs and DI engines into the CRV)... were not that fuel efficient for in town stop and go driving.

But if you want to resolve doubt... I'd say... fill the tank, and take a long freeway drive until the tank is approaching empty... refuel and note the gallons replaced, note the mileage from the prior full tank.... do the math.. and that will represent your normal top end highway fuel economy as currently configured. If you end up anywhere near 27mpg or better.. then you did well and have validated your particular fuel economy curve, and can back calculate expected city mpg from there.

 

[crv383]

Since your '06 EPA numbers are 22/27 (I guess), I would think in reality you would be getting more like 19-20/24-25 all stock. Through in the extra power train load of heavier/taller tires and 16-17 could easily be realistic, as you stated in your OP. As suggested, fill 'er up, drive and fill 'er up again......then do the arithmetic. Doing this multiple times tells you more about reality......much more accurate than guessing the affect of this, that, and the other or drawing early conclusions.

 

[PrksShl]

Getting about 17-21 on highway with this setup. So, yeah it will cost some mpgs.

 

[Wildcat]

Don't forget that in addition to the added weight of wheel and tire, and the additional strain on the engine moving that extra unsprung weight, that your speedometer (and therefore odometer) reading is going to be about 5% lower. A small amount but added to the other factors, is adding up to lower your mileage.

 

[Tigris99]

It never ceases to amaze me the people that modify their vehicles but dont have 1 clue about vehicles besides how to change the oil maybe.

Grade school science class taught these things. The heavier something it, the more energy it takes to move it.

Sent from my SM-N975U using Tapatalk

 

[PrksShl]

Didn't buy my rig for mpg for my rig it's a Good little rig. Cruises the highways well and it will do great as a fishing rig after winter. I just have to re learn the 5sp.

 

[kloker]

It's interesting the different result folks get. My '07 has 18" custom wheels that were installed by the dealer when the car came in new, as it was used for a showroom model. It has 255/18/R55 tires on it, and I get about 17 around town and 23-24 on the interstate. These tires are only 1" larger in diameter than the stock size, but they are much wider and heavier than stock ones, so I'm actually pretty impressed with my current mileage. I have, however picked up a set of the stock alloys from a 2011, and when I get new tires I will go back to the stock size. It might not look as cool, but the mileage should improve, and the stock tire size is much cheaper than these.