Downsizing question...31.10.5 to stock?

Just bought a 2000 Prerunner with Bridgestone Dueler's 31.10.5's.

I will be driving 95% on pavement and wondered what tire should I go to?

BUT...I want to stay with the stock size 225/75/15 and the choices are limited.

What tires would work best for the roads I will be driving?

 

Why would you want to downsize to a 28" tire?

I'm pretty sure.....the 1st gen trucks came with 31x10.50's (including Prerunners) from the factory. I had a 96 with 31x10.50's.

 

are you doing this for gas mileage? because with a magnaflow exaust, deck plate mod, and 32" mud tires im gettin 20 to 22 hwy.mpg's with a 3.4 v6 the 31 10.50's would be your best bet, there are alot of options for hwy tires.

 

I am getting crappy gas mileage with the Bridgestones.

Getting ready to install 5100's all the way around next week. And want to buy some high mileage tires to hopefully improve the mpg.

I am not opposed to, say, putting on Michelin MS/2's 31x10.50's but am wondering if I were to go back to 225/75/15's the mpg's would be better?

Also wouldn't the stock size with new Billy's ride smoother vs 31's?

Thanks for your help/suggestions!

 

You just bought the truck.....
What kind of gas mileage are you getting?
Have you performed any maintenance on the truck since you bought it?
What tire pressure are you running?
How many miles on the truck?

When you bought the truck - did you have any idea what the gas mileage is supposed to be?

Downsizing in tire size isn't going to miraculously change your gas mileage. The type of tire and having smoother shocks/struts isn't necessarily going to improve your gas mileage either (atleast not enough to notice).

 

Not all first gens came with 31 X 10.50's Many actually came with the 225/75/15's.. I am pretty sure the 31x10.50's came on the trucks with the factory alloys and the 225/75/15's came on the trucks with the steel wheels...

 

mine came with the 225-75-15's i have a plain jane sr5 4x4, but i lifted it, and done some other stuff and with 197,xxx miles its still puttin about 20mpgs out. the tires and suspension wont make a difference, change your plugs, put in a synthetic oil, and slow down a little..

 

He just bought the truck - so the question is.... are the 31's the original size that the truck came with?

Changing the tire size isn't going to make much (or even noticable) difference. Aside from that....he'll have speedometer changes & performance changes to deal with. That'll probably affect the gas mileage more than the tire size itself.

We still don't know what he's getting and what he thinks he's supposed to get.

 

Try 235/75R15. Many more tire options in that size. In my 94, the OEM tire sizes are 225/75R15 or optional 31x10.5R15. 265/75R15 is the same size but you can get it in LT (light truck) ply rating. Most 31s are 6ply (heavier) which will give you worse gas milage.

 

You just bought the truck.....
What kind of gas mileage are you getting? 17 mpg...mostly hwy miles
Have you performed any maintenance on the truck since you bought it? Nope, water pump, timing belt, and oil change done before I bought it. Currently runs just fine.
What tire pressure are you running? Good question...33 psi front & rear
How many miles on the truck? 106,000

When you bought the truck - did you have any idea what the gas mileage is supposed to be? Yep, based on informatio gleaned from this site...looking for 16 or so around town and 20+ hwy.

Not all first gens came with 31 X 10.50's Many actually came with the 225/75/15's.. I am pretty sure the 31x10.50's came on the trucks with the factory alloys and the 225/75/15's came on the trucks with the steel wheels... Bought it with 31's on it. And I do have the 15" alloy wheels

Changing the tire size isn't going to make much (or even noticable) difference. Aside from that....he'll have speedometer changes & performance changes to deal with. That'll probably affect the gas mileage more than the tire size itself. Matched up my hwy speed with my wife driving her RAV4 along side...at 70mph we were matched up side by side.

Thanks for the input...I'm getting the idea that putting 215's on will not appreciably help out my gas mileage.

I have yet to find a picture of a prerunner on this site with stock 15" tires and rims...it would be nice to see what a prerunner would look like with this setup.

 

just out of curiousity what m/t tires are you running?

 

A lot of 1st gens came with 31" tires. I had a '96 SX regular cab with the 2.7 and it came on 31x10.50 stock.

 

If you compared your speed with the Wife's RAV4 and your speeds were equal - then that'll tell you the 31" tires were original to the truck from the factory.

If you change tire size down to 28" - your speed WILL NOT match your wife's RAV4. All that speedo & mileage will change a bit because the rolling distance of a 28" tire is shorter than that of a 31"
Personally, I'd leave the 31's on and work on some maintenance.

Maintenance, maintenance, maintenance..... Have you:
Checked or changed air filter
Changed spark plugs
Changed oil & filter
Changed differential fluids, transfer case fluids, transmission fluid
Flushed radiator
Changed 02 sensors?
Run injector cleaner through the gas
(and that's only off the top of my head)

Maintenance does wonders for a variety of reasons. Since your truck has 106,000 miles on it and you don't know its maintenance history.....I'd get all the necessary maintenance done. Your truck will love you for it.

Cold weather and winter gas mixtures can negatively affect gas mileage also.

Also, I would check the trouble codes off the computer. See if there are any Check Engine Light codes stored in the computer. This might give you some clues to past history if there were any problems.

Also, search www.google.com and type in Tacoma Prerunner (use images). Lots of pictures.

 

Thanks Janster for the suggestions. Oil change has been done but I think I will have my mechanic check out the other fluids and filters. I'm pretty confident it has been regularly maintained...CARFAX shows that the oil was changed every 3,500 miles for the first 58,000 miles. Then the second owner who I purchased it from has records for the last <40k miles.

Good point abou the speedo matching up with the RAV4...I was thinking the same thing, that 31's were stock for this prerunner.

Well, I guess I'm going to be looking for the best deal for a set of 31's!

Michelins are pricey...I will check out this forum for some suggestions for a quiet riding, high mileage set of 31's.

 

Try 265/75R15, it's the same size as 31's but you can get it with less plys. Less weight equals better mileage and better braking. Why run a heavier tire if you don't need it.

 

Great suggestion Project.paradigm!

I can't get Michelin M/S in 31's at COSTCO (out of stock).

This gives me one more tire size choice!