Gearing A Cj5 To Match A Cj2 Torque

It seems that slapping 538 on my cj 304 would be a bit much does anyone have a formula to figure out the apples to apples

 

I saw some guys in cj2s on YouTube on the Rubicon they were kicking *** got me to thinking can I modify my cj5 in that direction

 

Granny gear four speed is the second best thing I’ve ever done to my Jeep. Power steering is number one for the skinny tree and rock strewn trails I run.

 

Looks like only mod was lockers sounds like crawl ratio would be the right measuring stick

 

A great rock crawler for the Rubicon would have a final crawl ratio of about 75:1. I had a 1945 mb it had 4:88 gears and a model 20 transfer case 2.03:1
and an SM420 4spd @ 7.05:1. which had a 70:1 final crawl ratio.
My 1978 cj5 had 4.27:1 gears T18 4spd 6.32:1 and the transfer case had the terra gears put in @ 3.15:1. final crawl ratio of 85:1.
My 1971 cj5 has 4.88 gears SM465 tranny 6.55:1 dana 18 TC 2.46:1 final crawl ratio 78.63:1

All these jeeps were perfect for the rubicon.

 

Interesting what's your power steering set up

 

What tire sizes and did you upgrade axles?

 

Off of a 73 cj with the 304 came out of the donor for my 304 and the boys front axle.

 

Now many of the jeeps that do the Rubicon have lockers. Front and rear are great. You just have to you them at the right times.
I have always had pretty small tires on my jeeps. 1978 had 33x12.5x15 1945 mb had 32x10.5x15 and my 1971 has 31x10.5x15

 

There is a circle of flat fenders known as the qwaazy8's on the cj2a page most of them are power steering, teralow gears in the transfercase, maybe a granny 4speed, dana 30 front, lockers and v6. Some are more some are less but lockers and low transfercase gears seem to be common. I don't think you will like 5.38 for everyday driving they are low and expect 35mph at 2000rpm. Technically 5.38 is a weaker pinion than 4.27 or higher so gearing down the transfercase is the best of both worlds and you only need to open one can of worms.