I have a 1990 camry dlx 2.0 4cyl 3S-FE, 4 speed auto trans with ETC w/188,000 miles but very well taken care of.

It says on the drivers door sticker that the tire size is 185/70R14. Right now it has 185/65R14 mud and snow tires, and has a mis-mached set that are all 185/75R14 on wheels that I want to replace with a matching set.

My question is how much can I increase the tire diameter/size to gain more gas mileage before they rub or effect the auto tranny?

I work in construction am unenployed ( big surprise there eh? ) and want to make it as fuel efficient as I can in case I have to take a job the requires a lot of driving.

Thanks

 

Not sure if changing tire diameter is the best route to higher MPG though the 185's would have a larger diameter.

The link below has a tire size calculator:

http://www.miata.net/garage/tirecalc.html

Doubt if the trans operation will be effected however the speedo will be "off" somewhat.

Tires can have higher and lower rolling resistance depending on tread design and construction. This can greatly effect MPG.

Tire pressure will also effect MPG.

Goodyear has a line of tires out that is supposed result in higher MPG but appear to have a shorter tread life.

A Google search should turn up sites listing tire resistance, tread life, etc for various tire brands and models.

You might calculate your max increase in MPG (and fuel savings) and compare this to the cost of new tires. You may find the payoff is much longer then you think.

 

thanks, I'll check it out.

Larry