decision on my build???

In a CJ6 I'd run and automatic. How about a 700r4? Or something with a overdrive?

 

I would run the 5.38's have considered it myself.
With the overdrive it would perfect and still have wheeling gears in first.

Look at the Novak site in the knowledge base you can get all the popular tranny info and they have the gear calculators there.

You will see that that the 700r with 5.38 makes alot of cence.

If you run a 4.3 with TBI then you would have the computor to plug a 700r into.
They were designed to have a lockup tourqe converter but if dont use the computor there are kit's for the trans to git around that.

You can get a manule switch for it, also and guys use that as a compression brake for slow down hill stuff.

I would look for a deal on a 4.3 with the 700r with it.
Have seen those on craigslist for 500.00 buck a couple times.
Guy's have wrecked chevy's and want to sell the drive train ect.

Depending on tire size.
Would be 60-80 to 1crawl ,taking into account the auto's extra tourqe.
And 2700 rpm = 65 mph. in overdrive.

 

I don't see where you mention tire size, maybe I missed it, and that makes a BIG difference in what gears you want to run. Figure out what size tires you want to run first then gear for that. On my TJ I run 33" tires with an auto and 3.73 gears. It's ok but really needs lower gears. 4.27 would return it to almost stock but I am going with 4.56's for a little better than stock off road. With that said, I would do the 4.3/th700r4. Just remember that the auto will effectively double your low gear because of the torque converter. And in California I would think you would want to be able to cruise at 65-70mph at least. If your planning on 31"s I would do 3.73 to 4.56 gears. If your planning on 33's then 4.56 to 4.88's.
Keith

 

Excess heating of the 5.38:1 differentials due to their high speed (with OD and engine swap) has been mentioned here before. How serious a problem is this?

 

I have a 62 CJ6, as well as several CJ5's, with the same stock set up. Not good for the highway but a blast everywhere else. I have a NT CJ7 on 33's, 4.10's, 4.3, quadrajet, SM465, NP205 and goes down the highway just fine.

Jeeps, especially open top Jeeps, were meant to be manually shifted (IMO). Don't hate the granny tranny - start off in second knowing you have the granny first when you need it.

As far as axles; swap in 72/73 Commando axles. Stock 3.73 gears and 11" drums. You can add discs up front, if you like, with very little effort. An offset 44 rear out of a late Kaiser 5 would really be nice.

I'm a fan of Saginaw but I've been wanting to try Herm's Ford RR upgrade.

 

Unless running 75-80 mph constantly I don't think it's a real issue. I've seen 5.38's burned up because they were run low on oil (bearings told the story on that one) and seen 'em break, but never a failure because of high speed running in a Dana 44. I've been running 5.38's since I got the '5 20 years ago and it was a daily driver for about 4 of those years on the freeway. Never had a gear failure related to high speed. Damaged 1 ring and pinion when the spider gears broke and got in between the r&p but that's it. By the way, Dana 44 spider gears don't like 2 nd gear wheel stands on dry pavement....R)
Nickmil

 

My B-I-L has a willys with a 327 and 700r and 5.38's.
Drive's it about an hour half every day to work and back in the summer no prob's.
Wheels auwsum in the woods.

Edit on 32's

 

How about a manule 5speed?
I had a s10 blazer with 4.3 and 5speed great rig good milage.

 

Personally I am going with 4.1's but no overdrive.
Something like 4.88 is probably a good comprimise.

 

FYI I plan on the stock Dauntless/T-86/D18 and 3.73s(i believe) with 31s or 32s eventually based on how it drives with the current 700-15s. There is a ford T-18 behind Dad's shed that I think I could install as easily as change gears.

I have run my 85 dodge with 318/727torqueflite/3.21s and 33s for years. It needs gears, but I just spend extra time in low side and use the torque converter.

 

Heresy, but I think the 700R4 would be a good swap to the CJ-6 with a 4.3L. The final drive ratio of the 700R4 is 0.7:1, so with 5.38:1 gears and a 31" tire, that's 2857 rpm. Shoot, my Golf with a 5-spd OD turns 3000 at 70, so 2800 should be fine. That's without a Warn OD - adding a Warn OD drops the RPMs to 2142, way too low IMO.

Your crawl ratio would be 40:1, which I think would be fine with an automatic - just learn to drive with one foot on the gas and one on the brake!

You'd also be well advised to upgrade the brakes with an automatic.

 

Uhh got me?:? I'm stiil re aligning the dialithiam chrystals and rerout power through the EPS conduit to stabilize the shields and boost the IDF field then prolly shunt power to the impulse engine. R)






Maybe I should have kept my mouth shut