So when are we turning up the pump? I've got a 4 day weekend coming up...
Can't wait to see that CUCV on those 39's.... Boggers rule, they are like magical offroad tires that go everywhere. For calculators, my favorite is here: http://www.4lo.com/calc/gearratio.htm
FWIW, I have a 35.35 crawl ratio, 2.73 diffs. 1.98 geared hubs, 2.72 T-case, and a 2.48 first. With the 42's it does fine 98% of the time crawling, the only time I run out of power is with steep hillclimbs (like the powerline hill on FWW) where I wish I had more gear to turn the 42's. Prior to the 42's I had 38.5 Swamper SX's and had zero problems at all in the same situations. My injection pump has been turned up 1/6th. In the future I plan to turn it up a tiny bit more and install lower gears in the transmission, a 2.75 first and 1.57 second. I do not want to touch the diff gears because I like the highway RPM's at 60, it is just right, with the stock 37's it revved way too much on the highway.
I think with the 6.2 and automatic with those tires, you will want it lower than 35:1. You could accomplish that by axle gearing, SM465, or doubler, your choice. I do not see the need for 80:1 crawl ratio with an auto though...
Edit, this company makes a 3:1 first gear for the TH400 (added to my list of future mods)
http://www.crttransmissions.com/Components.html
Can't wait to see that CUCV on those 39's.... Boggers rule, they are like magical offroad tires that go everywhere. For calculators, my favorite is here: http://www.4lo.com/calc/gearratio.htm
FWIW, I have a 35.35 crawl ratio, 2.73 diffs. 1.98 geared hubs, 2.72 T-case, and a 2.48 first. With the 42's it does fine 98% of the time crawling, the only time I run out of power is with steep hillclimbs (like the powerline hill on FWW) where I wish I had more gear to turn the 42's. Prior to the 42's I had 38.5 Swamper SX's and had zero problems at all in the same situations. My injection pump has been turned up 1/6th. In the future I plan to turn it up a tiny bit more and install lower gears in the transmission, a 2.75 first and 1.57 second. I do not want to touch the diff gears because I like the highway RPM's at 60, it is just right, with the stock 37's it revved way too much on the highway.
I think with the 6.2 and automatic with those tires, you will want it lower than 35:1. You could accomplish that by axle gearing, SM465, or doubler, your choice. I do not see the need for 80:1 crawl ratio with an auto though...
Edit, this company makes a 3:1 first gear for the TH400 (added to my list of future mods)
http://www.crttransmissions.com/Components.html
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