Best front axle swap to pair with rear Dana 44?

Find a matching narrow track Dana 30; most would have 3.73 ratio.

if you want drop in easy Dana 30 narrow track.

Hi Mark, we have a Chevy 350 in it, was a crate motor, not sure exact HP and Torque numbers, but it does pretty good. 

Hi Jedidiah,

To repeat what's been said, a narrow track D30 is a good swap but since you specified the "best", that would be a custom narrowed D44. Personal opinion, a D30 with chromoly axles shafts is very strong. you can convert to 30 spline (more on that in a minute)

What type of jeep are you trying to build? ... What are your priorities in order
Hi-way speed?
Crawlability?
Somewhere in between?
both?

Also, what transmission are you running?

I am running 3.73 gears. This is my experience. I love having the 3.73 gears to do interstate speed 65+ mph but if my intent were to drive 55-60, I think I would opt to drop my ratio some. Maybe 4.11 or something. I have no better mileage at 40 mph than I do at 65-70. In fact, it almost seems like my mileage is slightly better the faster I go. I assume this is because I have to go 65+ to get in my power band with the 4.3. My CJ5 with 350 chev and 3.73s was the same. ...

The down side is, 3.73s are murder on your crawl ratio. If your intent is to trail ride like the FCT or Black Hills, a stock 37:1 crawl ratio is fine and proven. 50:1 is even better but it is too fast if you are going to start technical rock crawling. If you want to be able to walk up on a rock without touching the gas, I recommend, at a minimum, 75:1 as oldtime said.

..... so, however you get the ratios is up to you, diffs, trans, TC gears. Back to the D30.... you can upgrade a D30 to a 30 spline to make it even stronger. If you plan on changing to a higher number (lower gear) you have to change the carrier housing anyway so you could change to a 30 spline locker at that time. Add chromolly shafts (30 spline), and you would have a very strong front axle assembly.

If you want to stick with the 3.73s you can go with a teraflex low kit and a T-90C gear set in the tranny to get close to 37:1 (trail gears). If you want the 75:1 (rock crawl) ratio, and the 3.73 hi-way gears, you will have to go to a 4speed truck tranny, SM420. 465, or T-18.

Sorry if I'm over explaining. I have a 3.73 hi and 77:1 low and I'm happy but if I had it to do over again, I might drop to 4.11 in my diffs.

Edit: I don't have as much experience as some so this is all FWIW.

Edited by jpet - 05 Apr. 2016 at 1:54am

Wow, thanks for the help guys.  A lot more to think about.  To be honest, I would love to be able to drive the Jeep on the road to "get there" and then on the trail both.  But maybe that isn't real feasible without a lot of money thrown at gearing.  Right now I tow it with the Land Rover to the trail, and then go from there.  I don't do it that often, but the road manners of the CJ2A leave a bit to be desired for any kind of road trip... 

You can purchase 11" brakes and just do the brake upgrade at this time till you figure out what to do.

I'm going to see if I can get that axle, as it looks like it fits the overall build plan. I'm willing to pull the 3.73s and gear it lower if needed. I'll have to see if I can salvage the Warn overdrive from my current setup or not. That might change some gearing ideas...

For the Dana 30 up front, would a Scout II axle work? There's one for sale near me. Or should I be looking at a specific year range of CJ5 only? Too bad it's wider than the offset D44 rear, but spacers wouldn't be too much of a weak link in the back, would they?
Thanks for all the tips, it's helping.

Thanks, that does help a lot. How are you guys getting such good crawl ratios? I just did the math, and surprised how bad the stock crawl ratio is on a CJ2A with T90 trans / Dana 18 combo. No wonder they went 5.38 gears!

If I do this axle swap, looks like I need to look real serious at a SM420 transmission or T98 / similar with a deep 1st gear. That would get my crawl ratio to something respectable, and I could leave the 3.73 or go with 4.10, etc, and not even need an overdrive for highway cruising.

oldtime wrote: Best advice...  That's a great rear axle.  Buy it for future needs but do not bother installing it till you come up with a real plan. It can take years to come up with a real plan and the parts to accomplish your goals. Research every little detail concerning your goal. In the meantime only fix what needs fixing the most. Then drive and enjoy. Let that experience be your guide.

This is good advise