Tire sizes requiring re-tune and/or re-gear

Diving deep and into all the tire/lift discussions. Debating between the 31.6 tires and true 32 skinnies (265/70/17 vs 255/75/17) along with a 1.5"-2" lift later. Both re-tune and re-gear are mentioned often at the 33"+ sizes, but not a lot of talk on the smaller diameter tires.

Do either of these require re-tune or re-gear (saw one skinny poster who said he did the re-tune for gear skipping)? Would these be 'preferred' for power/mpg/trans for either tire size?

I'm trying NOT to change too much to the truck.

Thanks!

 

IMO, I doubt you will notice a difference with those sizes. Re-tuning will help everyones truck, ha. But regearing is more for heavier rigs with 33's and up.

 

I’m running 265/75R16s (same as the 265/70R17).

I also have steel skids, rock sliders, and a RTT. Truck still runs fine. Yes there is a slight loss of power with the bigger tires. It feel like it takes just a brief second to get going but it’s not a race car in the first place. No re gear or tune for me although a tune may help with the power. Rehear isn’t necessary IMO.

 

Not enough difference to worry about with those sizes. In fact, your speedometer and odometer will probably be more accurate after you upsize. I wouldn't even think about re-gearing until I got to 34" or 35" tires.

Keep in mind that the dimensions listed for tires is when they are new. As tires wear down they are roughly one size smaller by the time they are worn out. If you replace a set of worn tires with new tires one size larger you are really going 2 sizes larger, at least when those tires are new. That may be enough to notice a slight difference in acceleration. But the difference is so small you'll never notice after a few miles.

The same thing happened when your truck was new with stock tires. As they wore down and got smaller your truck's acceleration actually improved. Your speedometer and odometer gradually got less and less accurate. But it happens so slowly that you don't notice. But when you buy new tires, even if they are the same size, you feel that difference as soon as you pull away from the tire shop.

ADDED:

Your lift will make a much greater difference in performance than the tire size. Once lifted your truck will catch more air that it has to push through.

 

I’m running 265/70r17s. I haven’t re-geared but I did go with an OTT tune. It helps with gear hunting but it doesn’t completely eliminate it. Rough country sells a speedometer calibrater that claims to adjust shift points for bigger tires. If you’re trying to keep changes to a minimum, it could be the best option for you.

https://www.roughcountry.com/speedo...y8E4hvNKcOjQtXhvu3R9IbA11lq7pOmsaAlcnEALw_wcB

 

I have 33s, full armor, winch, smartcap, etc…stock gears/tune and no issues

All trucks, driving styles, and expectations are different but like others mentioned, that jump in tire size should be negligible.

 

I have ran 265/70 285/70 and now 295/70 all without regearing. You need to look at weight as much as size. My 295 set up drives the same as my 285 simply because I dropped alot of weight off my wheels that balanced out the added tire weight. A tune is needed day 1 even on stock tires as far as I'm concerned.
I wouldn't lift it on that size personally I found mine looked goofy lifted on 265/70's

 

i wouldn’t dive too deep if i were you , just ask the company that will install them for you they can give you options

 

You mean 265/75R16?

 

yes, yes I do

 

Thanks for the info. I'll look at more 'looks' with those two tire sizes, commit to one and get 'em done, and then think about re-tune (no re-gear at all).

I've been eye-balling the ride/look of My Truck Thread (2021 TRD OFF ROAD 4x4) but I've also taken note of this thread (re sizing up from 265-75-16s to 255-75-17s) and some what seems like rare transmission issues - and Marshall, your inputs on the lift/air resistance likely being a bigger factor: https://www.tacomaworld.com/threads/32-tires-mpg-loss-and-gear-hunting.804978/#post-28861500