what kind of highway gas mileage are u guys getting with 185-60-14 or 195-60-14? i have the 175-65-14 and they are horrible. i just want to know what kind of gas mileage it'll drop me down to. hopefully not too much worse. also anything i can do about the speedo? thanks
You are correct that a wider tire will get reduced overall mileage due to the increased drag of the tire. I run a 205/45R16 and get about 29 to 30MPG with about a 10/90 mix of city and highway driving on a 2002 with an automatic with a passenger and office gear.
Generally - keeping every thing else the same - you can expect to lose about 1 or 2 MPG for every size you go up. But also consider the type of tire and amount of air pressure in them.
Kind of unusual that you have poor fuel economy with such a narrow tire. The OEM tires I had were Goodyear Integrity 175/65R14 and pumped up to 26PSI. I averaged about 30MPG on the highway. If I plumped them up to 35PSI and instantly got a bump to 35MPG. Bump up to 44PSI - the maximum "cold" tire pressure - and saw almost 40MPG. Granted the tire rode very stiffly, but for mostly highway riding - not much of an issue and I was still on the safe side of tire inflation.
Note that the tire will heat up under use and from the outside enviroment - sun shining on your car - but as long as you fall at or below the tire maximum cold pressure, stamped on the sidewall of the tire - you will be OK.
The tire pressure indicated on the placard on the door or inside the glove compartment is OK for all around use - good flexibilty and good road behavior for a mix of driving situations - but if you are mostly higway - pump up a bit more, they will run with less heat and reward you with better mileage.
Hope this help. Good luck.
