Axles Up
I'm currently in Iraq for my second time around, and I'm trying to figure out how to further the buildup of my '82 CJ-8 when I get back. My last trip paid for the Scrambler and some drivetrain modifications, and when I get back this time I'll be looking to keep rolling with it. I'm running a GM 350 with a NV3550 and a Dana 300, and was able to score some axles off of a '78 Chevy 1/2-ton. Unless y'all know better than I do, I'm currently running a Dana 44 and a GM 12-bolt. They're a little longer and a little taller than I wanted because they've been fliped under the leaf springs, but they should hold up fine. Among other things, I'm looking to go for some lockers and match the 33-inch meats with some 4.10s. I would like to go for an open differential that I can activate into a locker to lower wear and tear and maintain fuel economy, while still having some decent traction when I need it. I'm looking for something that will function as a daily driver, as well as something that will go where I want, when I want.
Unfortunately, my time and research capabilities over here aren't quite what I'd have if I were back home. I understand that some of my options are the Detroit Electrac, OX, Auburn Ected, and ARB. I'd like to hear what y'all think are my best options for cost vs. performance, etc. I'd also want the same kind for simplicity's sake for both front and rear. I'm also debating the Black Diamond XCL conversion to smooth out the ride my 4-inch Superlift springs. Other than being expensive, I haven't really heard much about this type of lift kit. Fuel injection and rear disc brakes are also bouncing around the back of my head. If you've got any thoughts on these or recommendations for other mods I can do, throw those at me too. Keep up the mag, its one of the things that keeps me thinking of the states whenever I can get a chance to read it.
Casey Crowley
CPT, AR
GM began phasing out the Dana 44 front axle for the GM Corporate 10-bolt in '77, so your front axle could be either. Although both diff covers have 10 bolts, the 10-bolt diff cover will have a more rounded shape and nearly symmetrical bolt hole locations (like the hours on a clock), while the Dana 44 cover will have a more oblong appearance and more irregularly spaced bolts. Also, the Dana 44 axle may have "44" cast into the centersection on the front of the axle near the diff cover somewhere. The '77-'88 10-bolt front axles have an 8 1/2-inch ring gear diameter and 28-spline, 1.20-inch shafts. Dana 44 front axles used in GM trucks in the early through late '70s have an 8 1/2-inch ring gear diameter and 30-spline, 1.131-inch shafts. Nearly any locker is available for the Dana 44 axle. If your front is a Dana 44, I'd suggest you go with an OX for your needs since it doesn't require any source of on-board air and there are less things that can go wrong with it. You just need to make sure the cable is adjusted properly when it's installed.
As for your rear axle, you already have it, so I'm not gonna bag on the 12-bolt too much, although it's not my favorite axle for a four-wheel drive vehicle. The 12-bolt rear axle stuck around in GM trucks until it started getting phased out in '79-'82 when it was completely replaced by the 10-bolt rear. The 12-bolt has an 8.875-inch ring gear diameter and sports 30-spline, 1.31-inch shafts that are of a C-clip type. Like a Dana 35 rear axle, if a shaft breaks the whole tire/wheel assembly can leave the vehicle. Moser Engineering, 260/726-6689, www.moserengineering.com, offers upgraded axleshafts for this axle and C-clip eliminator kits that will improve the strength of the 12-bolt greatly. For both the 10-bolt and 12-bolt, you're limited to an ARB if you want a selectable locker. Most of the others you mention are either in development or not available for the GM Corporate axles at this time.
If you don't like the ride of your Superlift springs, I'd try a different set of shocks before upping all the way to an XCL kit. I really like the Bilstein 5150s (800/537-1085, www.bilstein.com) that are on my flat fender. Many shocks control compression very well, but the Bilsteins seem to handle the rebound better than most, allowing for a more even ride. I run the softer 170/60-valved versions instead of the stiffer 255/70-valved shocks.