Question for those of you with 255 75 17 size tires

[alia176]

Lots of tires/wheel threads are on this board but trying to find out some specific info have lead to lots of reading with not much satisfaction. Hence I'm asking some pointed questions below! Hopefully this will help out others in the same boat.

Tire calculations came from this site: Calculator

My stock tire size is 265 65 17 (30.5" x 10.5").

I'm trying to decide between a set of 255 70 17 (31" x 10") 1.6% increase in diam. 70 mph will be actually be 71 mph

OR

255 75 17 (32" x 10") 4.9% increase in Diam. 70 mph will be actually 73mph

If you went with 255 75 17,

- P or LT?
- did you do anything for speedo correction? If so, what did you use?
- is the transmission still able to shift in/out of the torque curve properly?
- other than slower starting from a stop, any other adverse affects?
- any noticeable fuel economy hit with V8 or V6? Theoretically, econ should be better on long hwy trips.
- did you have to have a lift of (springs/spacers/or) some kind to prevent rubbing? I'm running FJC suspension so 1" or less of lift is what I got currently.

I'd like to take advantage of Memorial day sales at Discount Tires, hence the questions!

Thanks!

 

[who done it]

- P or LT?

- Not sure, went with Goodyear MTR Kevlar

- did you do anything for speedo correction? If so, what did you use?

- Nope, don't care enough. Not that big of a deal to me.

- is the transmission still able to shift in/out of the torque curve properly?

- Transmission works fine, haven't noticed any issues.

- other than slower starting from a stop, any other adverse affects?

- Truck is definitely slower, but doesn't bother me as it helps me keep my speed in check. Ride is a little rougher, but thats due to
the tires I chose.

- any noticeable fuel economy hit with V8 or V6? Theoretically, econ should be better on long hwy trips.

- Fuel economy definitely took a hit, around 3 MPG.

- did you have to have a lift of (springs/spacers/or) some kind to prevent rubbing? I'm running FJC suspension so 1" or less of lift is what I got currently.

- Running a 3 ish inch FOX 2.5 lift. Trimmed the front wheel liners as well as mud flaps.

 

[tucktuck8]

I went with 255/75r17 duratracs. They have knoby tread but are quiet on the road. I haven't noticed a reduction in power at all. I have a v8. I have a 3.5/2.5 inch lift and had to remove my front mud flaps and I still rub on my front bumper turning in reverse. My speedo is 3 miles an hour off at 65 miles per hour. My means for correcting the speedo are subtracting the speed reading by 3 miles per hour.

the 255/75r17 tire is the best size in my opinion. they fill the wheel wells without sacrificing power/gas mileage and they are much cheaper than most wider tires.

look at my build thread for pics.

 

[S p a r k y]

http://www.toyota-4runner.org/4th-gen-t4rs/178078-speedohealer-v4-4th-gen.html

 

[alia176]

It sounds like the 255 75 17s will be too big for my oem suspension. I agree, this size seems to be the optimum size.

Thx for the inputs.

 

[alia176]

I went with 255/75r17 duratracs. They have knoby tread but are quiet on the road. I haven't noticed a reduction in power at all. I have a v8. I have a 3.5/2.5 inch lift and had to remove my front mud flaps and I still rub on my front bumper turning in reverse. My speedo is 3 miles an hour off at 65 miles per hour. My means for correcting the speedo are subtracting the speed reading by 3 miles per hour.

the 255/75r17 tire is the best size in my opinion. they fill the wheel wells without sacrificing power/gas mileage and they are much cheaper than most wider tires.

look at my build thread for pics.

Did your fuel economy take a hit?

 

[jsmith21]

I had my 255/75r17 for about four months with no lift and only rubbing I had was full lock in reverse. I also had fifth gen wheels on mine though so that might be why.

 

[alia176]

I had my 255/75r17 for about four months with no lift and only rubbing I had was full lock in reverse. I also had fifth gen wheels on mine though so that might be why.

Well that killed my theory[emoji2]. So you can get by with no lift and this size tires, that's good news. What brand tires and P or LT? Fuel Econ hit?

 

[jsmith21]

Yeah, you can. I was actually very surprised too. I'll try and dig up some pics of how it looked with no lift and 255's if you want. And I went with Lt rated Goodyear Wrangler Mtr Kevlar, probably overkill for what I need but man they look sweet. And there was a fuel economy hit...but I think that's because I went from a 38 pound tire to a 53 pound tire. I lost about 2-3 mpg. I average around 16-18 depending on if I drive mostly city or highway. It did lose a little power too, but there's still plenty of power left.

 

[alia176]

Wow, that's interesting info indeed, thx for the info. So, the fifth gen wheels must push the tires out a tad and rubs less, I guess?

 

[tucktuck8]

I'm sure it did some, but nothing significant I have noticed. The in-car mileage calculator is very close to the same it was pre-lift.

I might have more rubbing than most because my FJ wheels are 15mm offset instead of 30mm AND I have wheel spacers.

We will see after inch front lift along with 1/2" BL

 

[Xrider237]

I might have more rubbing than most because my FJ wheels are 15mm offset instead of 30mm AND I have wheel

i just asked about this today in another thread- so basically your wheels are pushed out 1.85" from factory? 1.25" from ST and .6" from the fj wheels...have you ever read or heard any issues with this setup? thanks

 

[tucktuck8]

i just asked about this today in another thread- so basically your wheels are pushed out 1.85" from factory? 1.25" from ST and .6" from the fj wheels...have you ever read or heard any issues with this setup? thanks

Yes, that is correct 1.85" further out than stock. I was concerned at first but I have seen others with further spacing and no reported issues.

 

[XR250rdr]

I'm running 255/75-17 Hankook Dynapro AT-Ms.

- P or LT? P
- did you do anything for speedo correction? If so, what did you use? Didn't do anything.
- is the transmission still able to shift in/out of the torque curve properly? Trans works fine.
- other than slower starting from a stop, any other adverse affects? Can't tell a difference in acceleration.
- any noticeable fuel economy hit with V8 or V6?Theoretically, econ should be better on long hwy trips. I didn't have it long enough with stock tires to tell but I can get 19mpg highway if I keep speed at or under 70, sometimes close to 20 if I'm lucky. I have a V8.
- did you have to have a lift of (springs/spacers/or) some kind to prevent rubbing? I'm running FJC suspension so 1" or less of lift is what I got currently. Bilstein 5100s on highest setting and Moog FJC rear springs. Still had to do a little reforming of inner fender liner with a heat gun to eliminate all rubbing.

 

[alia176]

I'm running 255/75-17 Hankook Dynapro AT-Ms.

- P or LT? P
- did you do anything for speedo correction? If so, what did you use? Didn't do anything.
- is the transmission still able to shift in/out of the torque curve properly? Trans works fine.
- other than slower starting from a stop, any other adverse affects? Can't tell a difference in acceleration.
- any noticeable fuel economy hit with V8 or V6?Theoretically, econ should be better on long hwy trips. I didn't have it long enough with stock tires to tell but I can get 19mpg highway if I keep speed at or under 70, sometimes close to 20 if I'm lucky. I have a V8.
- did you have to have a lift of (springs/spacers/or) some kind to prevent rubbing? I'm running FJC suspension so 1" or less of lift is what I got currently. Bilstein 5100s on highest setting and Moog FJC rear springs. Still had to do a little reforming of inner fender liner with a heat gun to eliminate all rubbing.

Thanks for the info. It looks like you're running approx 3" of lift and still have some rubbing. That doesn't bode well for my nearly stock height suspension and 255 75 17s :crybaby:

 

[jsmith21]

Wow, that's interesting info indeed, thx for the info. So, the fifth gen wheels must push the tires out a tad and rubs less, I guess?

Yeah I guess so, because I only had minimal running in reverse at full lock when it was not lifted and even now that it is. Here's a pic I found of it with 255's and no lift.

 

[XR250rdr]

Thanks for the info. It looks like you're running approx 3" of lift and still have some rubbing. That doesn't bode well for my nearly stock height suspension and 255 75 17s :crybaby:

It was pretty slight rubbing on the very front of the fender liner.

See the dimpled area where I heated it up and pushed in the liner.

Full size: http://i.imgur.com/F9izld3.jpg

Rear was at stock height at first and no rubbing there.

 

[alia176]

Good info, thank you gents.

 

[alia176]

A local buddy had a set of four Michelin LTX 265 65 17s with 5,000 miles for $350. I picked them up and put this tire saga to bed for now. As advertised, these tires are extremely quiet and should do ok for the type of wheeling this rig will see.

Thanks for the inputs, hope this thread helps out others who are in a similar situation.

 

[Scaiza]

I had my 255/75r17 for about four months with no lift and only rubbing I had was full lock in reverse. I also had fifth gen wheels on mine though so that might be why.

Did you run your 255/75r17's on stock rims? Will they work with the stock rims?