What Axles to Use?

I have 2 jeeps right now. A '64 and a '60. In the spring, I will combine them both to make one nice jeep. The '60 has 5.38 gears, the '64 has 4.27 gears. I plan on dropping a buick 215 V8 in the finished jeep. What axles should I use? I plow snow with the '60 jeep and having 5.38's with a Volvo B20 4 cylinder under the hood works out really well. But with the 215, the 5.38's will really limit my top end, but I fear if I use the 4.27's, I may not get that same snow pushing ability, even though the 215 is a more powerful motor.
Just fishing around for opinions right now. What do you guys think is the better ratio for me? By the way, IU have the stock T90 trans and D18 transfer case. I Will plow with 215/75 15 tires and run 235/75 15 tires in the spring/summer/fall.

 

Boyink, with what motor? what size blade? I have a 6.5 footer.

 

I'd suggest you use the crawl ratio, top speed and engine RPM calculators on the Novak site to get an idea of how each combination will perform. http://www.novak-adapt.com/knowledge/gearing.htm

You should also have a T90C in your '64, according to Novak. Combining the T90C with the 5.38 gears will give you a decent crawl ratio of 46:1. Using a D18 transfer case gives you the option of the Warn/Saturn overdrive, which will solve your highway speed problems with the 5.38s.

Getting low gearing is usually expensive, so if you have the opportunity to use the 5.38 axles, IMO you'll be better off.

 

Tim, great info. thanks. whats a T90C? how is it different than the T90 in my '60? I was thinking of an overdrive to help out at speed with the 5.38's, but they are pretty expensive. would an overdrive with 5.38's run a lower rpm then a stock 3 speed with 4.27's?

 

Forget the fancy math, etc. If you want to drive the jeep on the road, 4.27s are the only way to go on an early CJ5. I had 5.38s with an O/D on Percival and happily swapped axles to 4.27s and never looked back. I don't plow with it, but Mike seems to be doing OK with his set up. The gearing difference between the T90 and T90c isn't such that you are going to notice, or miss anything. At least that is my experience.

BTW, putting a blade much bigger than 6.5 ft is asking for (eventual) trouble on your rig. We've seen more than one frame bent from plowing snow.

Eck

 

Walck's says "25% reduction in RPM" so I assume that means RPMs are multiplied by 3/4. Thats the same as multiplying the final drive ratio by 3/4: 5.38*0.75=4.04.

The T90C has a 15% lower 1st gear, 3.41:1 versus 2.98:1. See the T90 page on the Novak site.

 

What size tires are you going to run when you get it all together? If you are going to run larger tires you might want the lower gear ratio.

 

As mentioned in first post:
I Will plow with 215/75 15 tires and run 235/75 15 tires in the spring/summer/fall.

Nothing too big, so a low ratio like a 5.38 will not be offset by a bigger tire.

 

Sparky, I don't know if the shaft is the same, but that spare trans you sent with the truck has a very strange bearing retainer, much different than the CJ ones.

 

Mike,,,Love the "happy smile" on the snowplow. Your pic reminds me of my days growing up in Muskegon. We would get 12" of lake effect snow and play all day long outside....Good living.....

 

If I had to do that just to leave the house, I'd end up a hermit.

 

Mine clearly says T90C on the cover. I haven't pulled it apart to confirm anything. DanStew also had a T90C in his (which he may still have and might be convinced to sell). Mine is a factory V6 (I can only assume), so I am not sure why it has a T90C based on the Novak information.

From Novak's info on the T90:

 

Nah...... You were close. I am still not convinced mine isn't a T86 with a drunken assembly line person in Toledo. Do the covers interchange freely? I guess I will find out once it goes.