Tires: 185/65 or 195/65???

[justinswrx]

Its time for new tires for my 2001 Altima, currently have 205/60/15 but want to switch to a narrower tire for better mpg. Looking at 2 different sizes 185/65 and 195/65. Which would be the better tire for fuel efficiency? 185/65 is narrower but its also shorter than the 195/65.

For reference

205/60/15 is 24.7" OD
195/65/15 is 25" OD
185/65/15 is 24.5" OD

[GasSavers_BEEF]

realize that it may mess with your handling too. has nothing to do with fuel economy but you still have to have drivability of the vehicle in order to be safe. you can buy a lot of gas for the price of one repair after sliding off the road.

something to think about.

[kit352]

how about the same size but in a llr tire? that way the handling and diameters will stay the same but you should see the mpg increase.

[theholycow]

How is your Altima's gearing?

The small difference in tire sizes won't really make an appreciable difference in FE. I'd stick with the original size and try to get something that takes higher pressure and has longer treadwear.

[cat0020]

Anyone know how much weight difference there is in each tire?

Does all that rotational weight difference effect the fuel economy?

[theholycow]

Originally Posted by cat0020

Does all that rotational weight difference effect the fuel economy?

It's my opinion that it doesn't have much effect with a FE-conscious driver. The loss doesn't happen until you brake; energy put into rotating weight while accelerating is stored the same as in a flywheel.

[kit352]

the llr weights for his size are 22lbs for the 205 and 20lbs for the 195. Its been my growing opinion that the llr tires are almost always heavier from there normal tread equivalants. Im not sure if its due to the longer lasting compounds or maybe to help the mpg. I just swapped a set of llrs on my car and they weighed 2lbs more than the oems ones.

[Ford Man]

As close as the sizes of the three tires are I don't think it will change the handling or FE either one much. The only difference you should see is maybe just a little bit looser in cornering with the slightly higher sidewall profile of the 65's vs. the 60's. My '88 Escort was equiped with with 165/80/13's from the factory, but I have gone to a 14" wheel in the past few years and been running 185/75/14's and 185/70/14's without any issues with handling.

[justinswrx]

OE size for my Altima is 195/65, I don't think I would be to worried about dropping down to a 185 and having handling issues.

And as far as the weight difference, on a dissapointing note I actually switched to a light weight forged aluminum wheel that was 9lbs lighter per wheel than the stock steel wheel with hubcap and so no significant difference in fuel mileage. Same size wheel and tires

[kit352]

its been long debated as too how much of an effect on mpg rotational weight has. Im begining to see it has little. seems like a smooth hubcap surface has greater effects on it.