2014 Yukon SLT 4x4 5.3 - Ring & Pinion questions

[swathdiver]

I just ran outside to check my glovebox, and this is what I see...

View attachment 345540

Fourth row down, fourth column over: I see GU6 listed. So that means I have the 3.42 final drive ratios, right?

Yes 3.42 gears and yours is set up for maximum towing. It also has the 2-speed transfer case and the external transmission and engine oil coolers and 700 watt cooling fans.

6PB and 7PB are your front spring codes.

So, now that we know what your gear ratio is, your rpms are about 75 rpms lower than with the original tires (1626 vs 1698 (mathematically)). The tune will certainly wake up the truck and greatly improve transmission performance and likely will quell your desire for a lower ratio gear set... for a while anyway!

 

[Charlie207]

Yes 3.42 gears and yours is set up for maximum towing. It also has the 2-speed transfer case and the external transmission and engine oil coolers and 700 watt cooling fans.

6PB and 7PB are your front spring codes.

So, now that we know what your gear ratio is, your rpms are about 75 rpms lower than with the original tires (1626 vs 1698 (mathematically)). The tune will certainly wake up the truck and greatly improve transmission performance and likely will quell your desire for a lower ratio gear set... for a while anyway!

I just assumed I had a basic model. Cool to know it's got some upgraded hardware.

 

[swathdiver]

I just assumed I had a basic model. Cool to know it's got some upgraded hardware.

You can send an email or a text to GMC and they will decode that RPO sheet for you this way you'll know and learn what options and features your truck is equipped with.

 

[Foggy]

Is the "K5L" the 700 watt fan motor option on his ???
I don't have that on my 14 denali, but according to my RPO I'm exactly
200 units newer than the OP !

 

[Charlie207]

Looks like something upgraded.