Newb Re-gearing question

[RV4021]

Hi All,

I have a 2013 DCSB TRD Off Road. I recently had an Icon Stage 3 suspension installed and I am very pleased with it. I plan on adding the Icon bump stops (I think thats their name). I have 2016 Tacoma 17" wheels with P265/70R17 tires. I am wondering if I need to get regeared. I am not a mechanical guy by no stretch of the imagination. It seems like there are times when my truck is running at higher RPM's than necessary. Please educate me on what needs to get done before I need a costly repair or maybe get a bit better MPG. Thanks in advance for any input.

Robert

 

[Umbrarian]

Re-Gearing is needed if you run larger diameter tires. I am unfamiliar with what the stock tire diameter was for that vehicle.

Find out what it was, what gears it has, and this chart will tell you what you need to re-gear to to get back in the same band.

http://www.bushwacker.com/blog/how-to/gear-ratio-chart

 

[Dalko43]

An equation I've seen used to give you a rough idea of the optimal gearing is

Optimal Gearing = [New tire size (inches) * Stock gearing]/[old tire size (inches)]

I think there are other gearing calculators that also take into account RPM's and give you a more precise estimate, but the above equation should give you a ballpark idea of where the gearing should be.

 

[Adventurous]

Nope, the 265/70R17 is a nearly stock tire size that was spec'd from the factory with the 3.73 gears. Unless you've added a significant amount of weight to the truck or have future plans of going to larger tires a re-gear isn't mandatory at this point.

 

[battleaxe]

This is the site I've always used to give a good indication of gearing required:

http://www.grimmjeeper.com/gears.html

From what I remember, the v6 tacomas in an auto are the A750F.

Your RPM's will look like this for 70 mph:

Gear RPM
1 9769
2 5662
3 3886
4 2775
5 1998

Mind you... Thats for a second gen Taco. I don't know if the third gens are that much different.

In my opinion, with a 265/70/17, you really shouldn't notice a huge difference.

 

[RV4021]

Thanks for all of the replies! It looks like I have a little bit of research to do. Thanks again for helping me out.

Robert

 

[dorton]

When does it run at high RPMs? For instance, is it only when cruise control is set?

 

[DaveInDenver]

Adding to the thoughts, re-gearing to achieve stock RPMs with taller tires isn't always necessary. Going up a size or two in tire gives you a built-in overdrive that may be desirable if you can tolerate the reduction in low range. The 2nd gen automatic trucks have a decent stock final drive so keeping it is nice but in my stick shift the 6th gear really isn't all that tall so I decided to stay put at my modest 3% loss with slightly taller tires since it brings my RPMs down a little at 70 MPH.

 

[RV4021]

The truck seems to get "stuck" at higher RPMs when I am on the freeway. If I let off of the gas a bit it shifts gears and drops the RPMs.