18" or 20" best for towing or either?

Recently purchased a '20 CM SR5 4x4 that came with the stock 18" 5 spoke aluminium wheels with ugly 255-65 all season tires. I want a little bigger AT tire to make the truck look better instead of a 2wd. I also prefer the look of the "limited" and "trd" wheel. So before i buy tires i need to decide if i want to stay at 18" or pick up some 20" limited take offs. (I pull a travel trailer more often that i use the 4wd) So my question is: would the truck tow/ride better with 18" or 20"? Or does it even make a difference? Thanks for the replies in advance.

 

Wheel size doesn't matter for towing unless you want to consider adding a big brake kit in the future. BBKs only fit on 20" and up wheels. Now if you want to talk micro performance for towing.. you basically want as little rotational mass as possible, which can be done by experimenting with different wheel and/or tire sizes. That being said, obviously if you go up in tire size then you're adding more rubber and more rotational weight per corner. As a result, more stress on the drivetrain. IIRC, each pound off rotational weight is equal to 10 pounds of extra weight on the drivetrain. If you're just going up an inch in tire size.. you won't notice anything essentially.

 

Keep your 18s and go with slightly bigger rubber. 275/70s fit great on stock suspension and add some beef. 18 inchers will ride better when unloaded and handle towing just fine. To further improve your towing and handling, add the TRD rear sway bar and you will be golden.

 

picture of that size on a stock truck for reference

 

IMO 20" are better for towing as there is less sidewall flex, providing better stability for trailer sway control. (assuming you stay close to stock tire sizes)
Basically anytime the truck is side-loaded: corners, winding roads and high winds.
IMO 18" ride more comfortable because there is more sidewall flex to help absorb bumps in conjunction with the suspension.
I Have a Tundra Sport (20" wheels with front/ rear TRD sway bar), my dad has a Tundra Offroad (18" wheels standard front sway bar only).
His truck rides much smoother on country roads. My truck is a little stiff but drives flat and planted on the highway when towing.
I am honestly looking for a set of 18's to soften up my ride a little.

 

Looks good. That is also the style wheels i prefer over mine but the only take off i can find are 20's. Thanks for the pic. Better than words anyday.

 

Thanks for all the thoughts, comments and opinions.

 

This is what I was going to say, having owned a platinum before this trd or. The platinum with 20s towed way better than the trd. But the trd handles dirt roads or bumpy roads like a champ.

 

Can for sure tell a difference between the 20 and 18 I installed. The 20 on the Sport are for sure better handling in turns and being aggressive with maneuvering. I would imagine if you have high tongue weight, they would have to tow better.