Based on what Robbie knew at the time I went with 4.10 from the 5.13's it had in it. With 35's they are OK but I still hit the rev limiter fairly easy unless I use the manual shift. These motors rev so quickly it is almost impossible to control in full auto! I would consider 4.56 or even 4.88's depending on your usage. Four low except for crawling is about useless so this is another consideration. You can tune the transmission to be more aggressive so with 4.10's it will not feel so sluggish. The stock tune is set up to be the most efficient so it will hold the motor at the lowest RPM possible to get the BEST mileage. Turning off AFM, automated fuel management or cylinder de-activation, and making the shifting more aggressive makes these motors feel more like a sports car but expect less efficiency!! Bigger tires, lower gears, full armor less efficiency! It all adds up! But man it is fun when you get into it! Want to get creative create several tunes, just like the diesels depending on what you are doing for the day! Haven't looked into it to see if the E38 ecu supports it or not but maybe even on the fly tunes with a selectable switch! So many options no time!!
2008 Sahara 2011 LS5.3 6spd. auto 30/44, 35" NITTO's, 4.10 gears with TrueTracs front and rear, 3.5" Metalcloak game-changer ARB, front track bar drop and drag link flip steering box cross brace to passenger frame rail, PSC pump and reservoir. EFI Live tune on motor.