Crawl Ratio for JKU w/ LS3, Auto

[sc_rhino]

Back when I had my 3.8, rubi transfer case, and 5.13s I had around 93 crawl ratio with a manual trans. Now that I've got a v8, auto, 4.56s, and a non-rubi transfer case my crawl ratio is around 50. I'm thinking I want a higher ratio but don't know how high to go (future info, won't be doing anything for a while).

I've been playing around with crawl ratios at the website called grimmjeeper. It lets you play around with different transfer case ratios, diff ratios, tire size, transmissions, to get rpm, mph and crawl ratios.

In the following picture, I have entered my info (4.56s, 2.72 transfer case, 6L80) in addition to Moby's info (5.38s, 3.0 transfer case, 6L80). Our crawl ratios are very similiar with 2 Hi and 4 Hi, but Moby's 4 Lo is 65 vs my 49.



So for me to get around the same crawl ratio as Moby, I need an Atlas 3.8 which gives me 69 or an Atlas 4.3 which gives me 79. Was just wondering what's everyone's thoughts about what is the "right" crawl ratio?

Also, my thinking is to stay at the highest diff ratio (lowest number) to get the best mpg and use a higher number transfer case as opposed to the other way around.



In the above picture my rpms are around 200 less in 6th gear running 70 which lately I'm getting from mid 14s to 16s.

 

[RMC2]

Liston, You said you liked how it drove on the highway, so I would focus on the transfer case ratios.

For the rocks, I like the lower ratio of rubi case. It gave more slow speed control. I just switch back and forth between 2h, 4h, and 4l depending on the section of the trail. Maybe the 3.8 ratio.

Then there is always the three or four speed transfer cases.

Do you see 40s ever, worth considering in the equation.