Gears Upgrade

[Luis Aguilar]

Hey guys, I want to know what gears you all recomend for my 5.3 2014 Sierra, right now it has the original Gears. My truck has a 9 inch lift with 22 rims and 35 tires. Im looking for a better MPG and more power the truck is a 2wd.

[300 Blackout]

Hey guys, I want to know what gears you all recomend for my 5.3 2014 Sierra, right now it has the original Gears. My truck has a 9 inch lift with 22 rims and 35 tires. Im looking for a better MPG and more power the truck is a 2wd.

There were three options for the original gear ratio. If your truck came with 3.42 or 3.73 from the factory, it’s an easy swap. If it came with 3.08 there’s a couple extra parts you need to make it work but it’s still doable. I recommend going to 4.56 or 4.88.

Since you have a 2wd truck, upgrading your driveshaft is an absolute must if you ever want to drive at highway speeds. The driveshaft on your vehicle is longer than the 4wd trucks and its going to be dangerously close to it’s critical rotational speed. Also plan on some sort of a tuner in order to update the computer for your tire size and gear ratio.

[Jacoby]

4.56

[Yondu]

What transmission?  Not sure how many 8 speed 2wd trucks there are, but 4.10 would be better if you have the 8.  Otherwise 4.56 unless they make something between.  

 

I have 33s and would like 4.10 once the warranty is up. 

[1SLOW1500]

I say forget the gears and bolt on 300 more ponies. More funner and it will get the truck moving. I have 550-600rwhp and with 24" rims and 3.42 stock gear, crew cab and just heavy. Still on expressway 20mpg. People that drive it say it take no throttle at all to move it. 1k rpm cruise at 50mph.

Also in tune you can bump up that mpg. And still change for the tire and the gear if wanted.

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[Yondu]

With the lift (worse aero) and 35" tires I'd think that would be a predetonation nightmare with a blower on it, unless he has the stock 3.73s and then he would just get by.  Chances are it's a 3.42 truck and if it's a 3.08 geared truck it's begging for gears. 

 

 

[1SLOW1500]

3.08 gear is a begging to we swapped out. But on a turbo that would be a nice gear. Say in the boost curve a little longer. After all a 6 speed has your cruise speeds covered anyways. Supercharger isn't by choice as it would benefit yes but supporting mods are recommended. With the charger being belt driven it is linear to rpm. So you are correct stall gear and final ratio. Superchargers have much more stress on the engine. So the additional stress of lift and wheel do not help.
As for drive shaft. I like the smaller diameter 2 piece.

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[Yondu]

Different strokes I guess.  I've never had a turbocharged vehicle, I did put tvs1900s on my last two rides and they're pretty awesome.  Last one was on for 55k before I sold it and never once had to tweak it or work on it once I got the tune/ pulleys right.  

 

You do have a more hard limit with a supercharger as to how much power you can make but they always made what I was looking for, modest low 500s whp, tapped out around 600 from what I've seen on the 1900s.  I'm not much for pushing the limits and having to fix stuff all the time anymore.  TVS blowers are a install it and forget it type of thing. 

[Luis Aguilar]

7 hours ago, 300 Blackout said:

 

There were three options for the original gear ratio. If your truck came with 3.42 or 3.73 from the factory, it’s an easy swap. If it came with 3.08 there’s a couple extra parts you need to make it work but it’s still doable. I recommend going to 4.56 or 4.88.

Since you have a 2wd truck, upgrading your driveshaft is an absolute must if you ever want to drive at highway speeds. The driveshaft on your vehicle is longer than the 4wd trucks and its going to be dangerously close to it’s critical rotational speed. Also plan on some sort of a tuner in order to update the computer for your tire size and gear ratio.

 

Right now the ones i have are 3.42. Whats the difrence between the 4.56 and the 4.88, and whats better

[aseibel]

12 hours ago, Luis Aguilar said:

Im looking for a better MPG and more power the truck is a 2wd.

You can't really have both. Higher gear ratio will give you better power/acceleration, but increase your rpms on the highway (more fuel burned). Lower gear ratio makes it feel sluggish, but lowers engine rpm (less fuel burned).

 

With a lift and larger tires, the truck would be more exciting to drive with taller gearing, but you will never get back the MPGs you lost with the mods you have done.

[FlipZ71]

4.56 , was the second best mod I've done 

[Dezrado]

On 8/18/2019 at 5:46 PM, FlipZ71 said:

4.56 , was the second best mod I've done 

What brand and where did you buy them?

[FlipZ71]

1 hour ago, Dezrado said:

What brand and where did you buy them?

I went with Revolution Gears. They have a 2 year warranty...  and believe they actually make the ones for Yukon... not sure , but the revolutions were about $275. Cheaper ...