18 Feb 08, 05:40 pm
Right now I have about everything to get my CUCV ready for my 39" tires. All I'm waiting on are the wheels which will be in town later this week. I was hoping not to have to get my drivelines lengthened with the 6.5" of lift, but I'm pretty sure I'm wrong. I was planning on installing a 203/205 t-case doubler and getting new drivelines later.
So I was reviewing what my crawl ratio would be and found out some interesting data:
Right now I have a TH400 / 208 / 4.56 gears, so 2.48 (TH400 1st gear) x 2.61 (208 low) x 4.56 = 29.52:1 crawl ratio.
If I install the 203 / 205, it will increase my crawl ratio to 44.78:1. 2.48 (TH400 1st gear) x 1.98 (205 low) x 2.00 (203 low) x 4.56 = 44.78.
I got to thinking about my other truck which as a SM465 / 208 / 4.56 gears. 6.55 (SM465 1st gear) x 2.61 (208) low x 4.56 = 77.96 crawl ratio.
The SM465 really is geared low and makes a tremendous difference in the final ratio. If I lifted this other truck, I would not have to spend the $1,000+ for the doubler. I'd have to buy longer driveshafts in either case. Any mistakes in my math for the crawl ratios?
I understand that some people don't like a manual for crawling, but heard a hand throttle helps a lot here. I've also heard that automatics do better for mudding (mud drags in particular), but I don't expect I'll be in too much mud. I really like the trail rides we've been doing around Fairbanks and want to hit some rocks this summer. Are there any benefits from an auto that I'm missing?
So I was reviewing what my crawl ratio would be and found out some interesting data:
Right now I have a TH400 / 208 / 4.56 gears, so 2.48 (TH400 1st gear) x 2.61 (208 low) x 4.56 = 29.52:1 crawl ratio.
If I install the 203 / 205, it will increase my crawl ratio to 44.78:1. 2.48 (TH400 1st gear) x 1.98 (205 low) x 2.00 (203 low) x 4.56 = 44.78.
I got to thinking about my other truck which as a SM465 / 208 / 4.56 gears. 6.55 (SM465 1st gear) x 2.61 (208) low x 4.56 = 77.96 crawl ratio.
The SM465 really is geared low and makes a tremendous difference in the final ratio. If I lifted this other truck, I would not have to spend the $1,000+ for the doubler. I'd have to buy longer driveshafts in either case. Any mistakes in my math for the crawl ratios?
I understand that some people don't like a manual for crawling, but heard a hand throttle helps a lot here. I've also heard that automatics do better for mudding (mud drags in particular), but I don't expect I'll be in too much mud. I really like the trail rides we've been doing around Fairbanks and want to hit some rocks this summer. Are there any benefits from an auto that I'm missing?
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