Flog me if needed, but I gotta ask (Gearing)

I'm trying to wrap my head around what re-gearing does to an auto transmission on our trucks. In my case, I have a stock TRD Pro with an auto transmission. If I were to re-gear to the next smaller gear ratio to raise RPMs and make towing a little easier would that accomplish that or would the transmission just shift to the overdrive gears quicker. I read on another thread that explained the complex algorithm these trucks use to decide on gear selection so Is the truck to "smart" to re-gear?

 

Regear will help. It will lower your final drive ratio so what ever gear you are in including over drive gears, your truck will pull better.

 

The "sport" shift setting in our trucks can also be used to lock out gears so your truck does not shift into the overdrive gears while towing.

 

Get a bigger truck

 

Helpful

 

When towing do you just roll in 4 then?

 

Depending on how heavy a load yes that is ideal. If I am towing my small trailer, less than 1500 loaded, I keep in drive with etc on.

But to answer you first question. Regear will help a lot, depending on what gear ratio you go to. If you are keeping stock tire size and just need a small improvement maybe 4.30, or are going big tire and need 5.29s. 4.88 seems to be sweet spot for 33’s to 31’s.

 

So at any given speed and gear your rpm will be about 250-300 rpm higher. For each ratio you drop a ratio.
So your tranny will still shift at whatever rpm it is programmed for, your mph will just be lower at that given rpm.
So if you 4-5th shift is at 5k rpm now and you doing 50 its will shift at around 45 with 1 lower ratio.
It doesn't affect your tranny, the leaverage of the lower gear ratio just adds mechanical advantage to what your tranny output is.

 

Thanks!