4.stupid

hammer11b

is 2020 over yet?
Joined
Aug 19, 2020
Location
charlotte
Ok ha ha yes I know. >p

Yes the engine is still oem spec. I just bought it in July 2020 from an old dude that just used it to drive his rv or whatever to phoenix and back every year. Garage kept and everything. I've done a bunch of research on the weaknesses and all that and am trying to do this right. Regardless of engine or transmission, increasing tire size reduces final drive ratio. Eg. 3.73 down to 3.25 (idk what the theoretical ratio is) Period. Thus putting more stress and causing unnecessary wear and tear on parts that don't need it. Why should I add power when mechanical advantage will do the same thing and remove and replace all the bearings and such in the axles?
Am I dead set on getting different gears installed? Yes. Absolutely yes. All day yes. I am sorry some do not agree. Thats fine. What ever. I was only asking those more experienced in these things which way I should go.
 

77GreenMachine

Phillip Talton
Joined
Mar 30, 2010
Location
Trinity, NC
This makes no sense to me. I can't count how many trucks just like yours who are running up and down the road with 35s, even 37s on stock gears. A good tuner that firms up the shifts, locks in the converter sooner, and gives better throttle response will take care of all your concerns. You'd also see MPG improvements. It wouldn't hurt at all to add 4:10 gears, but best bang for your buck is going to be a tuner. Smarty for the win. Fix the tach, get a tuner, then decide if you want to upgrade the valve body.
 

hammer11b

is 2020 over yet?
Joined
Aug 19, 2020
Location
charlotte
Yes I see the irony in oem mpg and 600 hp monster. Oem mpg was just an example of me trying to build a solid foundation to build off of.
 

Stuntman Autoworks

Instigator of things
Joined
May 6, 2010
Location
Sanford NC 27330
But adding power(fuel) also increases fuel consumption (mpg-) rt? So wouldn't be wiser in the long run big picture to change the gears? Esp if I'm adding big power later?
Fuel consumption is directly related to the position of the right foot of the operator.

If you have the money regear to 4.10
If you are going to build a mild 600hp truck you might as well go ahead and put in a built trans. The improved shifting and holding power of a valve body and triple disc converter will likely surprise you with the drivability it brings back.
 

CLRracer

Mopar Nut
Joined
Mar 20, 2005
Location
Archer Lodge
But adding power(fuel) also increases fuel consumption (mpg-) rt? So wouldn't be wiser in the long run big picture to change the gears? Esp if I'm adding big power later?

Tuning does more than just throw fuel at the engine and make more power. There are a lot of variables changed by good tuning. Not apples to apples, but changing tuning in my 15 made my mileage go up. And I agree with everyone else, gearing isn't where you should be looking, but if you're dead set on it I wouldn't go deeper than 4.10. I have one Cummins on 35s with 3.54 gears and one on 37s with 4.10s, in neither of them have I wished I went to 4.56.

Duane
 

Stuntman Autoworks

Instigator of things
Joined
May 6, 2010
Location
Sanford NC 27330
Yes I see the irony in oem mpg and 600 hp monster. Oem mpg was just an example of me trying to build a solid foundation to build off of.
You have the truck, that IS the solid foundation. I do not agree with the smart tuning though, I would suggest a good competent efilive tuner.
 

hammer11b

is 2020 over yet?
Joined
Aug 19, 2020
Location
charlotte
Worried about MPG and don’t listen to solid advice from people in the know. Just like all the Prius drivers I know. Tune it, gear it, trans swap it are all solutions but the best solution is to put it back stock if you are worried about MPG.
Mpg is a bonus. I want a solid foundation. Why is this hard for anyone to understand?
I genuinely thought this was a simple question but forgot internet rules.

Thank you all for your responses, but imma head out now.
 

CLRracer

Mopar Nut
Joined
Mar 20, 2005
Location
Archer Lodge
Mpg is a bonus. I want a solid foundation. Why is this hard for anyone to understand?
I genuinely thought this was a simple question but forgot internet rules.

Thank you all for your responses, but imma head out now.

Your foundation is already solid. If anything the weak part of your foundation is the transmission. I would spend money there before gears.

Duane
 

Ron

Dum Spiro Spero
Moderator
Joined
Apr 16, 2005
Location
Sharon, SC
Mpg is a bonus. I want a solid foundation. Why is this hard for anyone to understand?
I genuinely thought this was a simple question but forgot internet rules.

Thank you all for your responses, but imma head out now.
You have a couple of the best gear installers on the east coast who make their money installing gears telling you that you dont need to regear.
Think that through.

If you just want to regear, cool go for it.

But let me explain it for you.
That truck should have come with
235/80/17 tires factory stock.
That tire is 32" tall.
You've now increased to a "35 inch" tire that is 34.75 inches tall per toyo specs


So to calculate the effective drive ratio impact divide 32/34.75 = .9208

Now take your existing 3.73 and divide that by .9208 and you will get 4.05

So if you re gear to a 4.05 it will be the same rpm equivalent to what you had and in theory same throttle responsiveness.
That isnt perfect because the new tires weighs more and the increased height has higher drag etc.

But if you coudl put it in a vacuum a 4.05 gear ratio would compensate for the difference in tire height.

Or like Jody said 4.10 and be done with it.
 

rcalexander105

JV Wheeler
Joined
Nov 3, 2017
Location
High Point
:popcorn:

This is the most interesting thing on the forum in weeks. I thought this place was on life support.
 

hammer11b

is 2020 over yet?
Joined
Aug 19, 2020
Location
charlotte
You have a couple of the best gear installers on the east coast who make their money installing gears telling you that you dont need to regear.
Think that through.

If you just want to regear, cool go for it.

But let me explain it for you.
That truck should have come with
235/80/17 tires factory stock.
That tire is 32" tall.
You've now increased to a "35 inch" tire that is 34.75 inches tall per toyo specs


So to calculate the effective drive ratio impact divide 32/34.75 = .9208

Now take your existing 3.73 and divide that by .9208 and you will get 4.05

So if you re gear to a 4.05 it will be the same rpm equivalent to what you had and in theory same throttle responsiveness.
That isnt perfect because the new tires weighs more and the increased height has higher drag etc.

But if you coudl put it in a vacuum a 4.05 gear ratio would compensate for the difference in tire height.

Or like Jody said 4.10 and be done with it.
Best answer yet.

Who tf is marty?
 

hammer11b

is 2020 over yet?
Joined
Aug 19, 2020
Location
charlotte
Your foundation is already solid. If anything the weak part of your foundation is the transmission. I would spend money there before gears.

Duane
I'm pretty sure this is my new route.
Trans then gears then tune.
Thank you
 

jeepinmatt

At least half the people are dumber than the rest
Joined
Mar 24, 2005
Location
Stanley, NC

83oldyoda4x4

Well-Known Member
Joined
Jan 13, 2008
Location
Randolph co, NC
So one night in the garage I see some 37s that were taken off a jeep someone bought. And then I see an extra set of wheels I had.. couple beers later... BTW 37s will clear with a small level. G56 and 3.73s I actually liked it you could use 1st gear lol. Unfortunately they were mudgrapplers so the experiment ended not long after.

Screenshot_20210210-201414_Gallery.jpg
 
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