What gears are factory and what should I run ?

[j91z28d1]

Your Denali has 3.42 gears and if you want to have about the same effective ratio (a little lower) with 37s run the 4.56s.

You do not need to change carriers in either axle for up to 5.13 gears.

You may want to consider getting the larger rear axle from the RWD Denalis and Escalades, 2007-2013, the 9.5" 14-bolt semi-floater. That can often be had for a song at LKQ. Again, that carrier will handle up to a 5.13 gear.

Remember that those AWD transfer cases demand that the tires be within 1/8 inch in height of each other.

I was going to say there's a gear calculator online. just punch in before and after tire size and it will spit out what gear you need to run to keep the stock ratio..

going rised big tire off road is kinda like going drag racing. it's very expensive if you're not doing it yourself. Maintaining the mods also goes up a lot. as everything wears faster and breaks sooner.

both are fun thou. good luck.

 

[OR VietVet]

Knowing what you just said about being mechanical, do not try to do the work yourself.

 

[swathdiver]

I was going to say there's a gear calculator online. just punch in before and after tire size and it will spit out what gear you need to run to keep the stock ratio..

going rised big tire off road is kinda like going drag racing. it's very expensive if you're not doing it yourself. Maintaining the mods also goes up a lot. as everything wears faster and breaks sooner.

both are fun thou. good luck.

I made a calculator with excel that's very precise and even accounts for tread depth. Here's an example of my compact one:



This is about what the OP is experiencing now:



And this is how his truck would perform with 4.10 gears:



So if you compare the before and after, you guys were correct and I was wrong about the 4.56s being more equal, the 4.10s would be more equivalent while running 37s!

That's why I made this! LOL

 

[Jonpen]

Your Denali has 3.42 gears and if you want to have about the same effective ratio (a little lower) with 37s run the 4.56s.

You do not need to change carriers in either axle for up to 5.13 gears.

You may want to consider getting the larger rear axle from the RWD Denalis and Escalades, 2007-2013, the 9.5" 14-bolt semi-floater. That can often be had for a song at LKQ. Again, that carrier will handle up to a 5.13 gear.

Remember that those AWD transfer cases demand that the tires be within 1/8 inch in height of each other.

Can you explain to me a little more what you mean the tires have to be within 1/8 of each other

 

[Jonpen]

Knowing what you just said about being mechanical, do not try to do the work yourself.

I have a mechanic

 

[swathdiver]

Can you explain to me a little more what you mean the tires have to be within 1/8 of each other

The tire heights have to be as close as possible to prevent damage to the axles and transfer case. You don't want tires on the same axle to be different heights nor do you want there to be more than 1/8 inch different in height between tires on the drive axle compared with the tires on the steer axle. This will cause the tires to be turning at different rpms causing undue stress on the clutches in the locker when engaged and in the planetary in the transfer case in your case.

 

[Jonpen]

I made a calculator with excel that's very precise and even accounts for tread depth. Here's an example of my compact one:

View attachment 402949

This is about what the OP is experiencing now:

View attachment 402953

And this is how his truck would perform with 4.10 gears:

View attachment 402954

So if you compare the before and after, you guys were correct and I was wrong about the 4.56s being more equal, the 4.10s would be more equivalent while running 37s!

That's why I made this! LOL

Does that also include having the 22x14 wheels as well ?

 

[AJMBLAZER]

The wheels make no difference other than adding weight the truck has to spin.

 

[Dustin Jackson]

I’ve been told that my 3.73 gearing wasn’t enough for my 32 inch tires

 

[Marky Dissod]

GM under-gears nearly everything they make - trying to satisfy CAFE MpG tests and avoid fines.

... been told that 3.73 wasn’t enough for 32" tires

4.10 would DEFINITELY be better - city MpG would improve, enough to overcome the highway MpG penalty, at least for me.

... So if you compare the before and after, you guys were correct and I was wrong about 4.56 being more equal, 4.10 would be more equivalent while running 37s!

If 4.10 is 'more equivalent' to GM's OE gearing, then 4.56 would be better.