Use 'Em If Ya Got 'Em
I would like to put a 360 engine and 727 Torqueflite tranny combo in my '77 CJ-7 and retain the stock Dana 20 transfer case. Is this going to be relatively simple or is it easier to use a Dana 300 T-case?
Michael Bix
Clarinda, Iowa
If your ultimate goal is to retain your Dana 20, you can use an aftermarket adapter from Advance Adapters (advance adapters.com) or Novak Conversions (novak-adapt.com). As for using the Dana 300 instead of the Dana 20 behind the TF727, I'd say it's a pretty good plan considering the added power of a 360. Comparing completely stock t-cases, the Dana 300 has larger output shafts and slightly more durable gears. You should be able to find a good used Dana 300 that will bolt straight to the back of the TF727 for less than the cost of the aluminum adapter to retain your Dana 20. It would be a good idea to eventually convert either of these T-cases to a 32-spline rear output shaft (both Advance and Novak have them) if heavy throttle or big tires are in you Jeep's future.
Buggy Bugging
I am getting ready to start on a DJ project similar to your flattie. My question is in regards to shackle hangers. Do you know anything about M.O.R.E.'s buggy spring shackle mounts? I noticed you did not use them on your project. My biggest concern is their stability on the highway. I suspect I will trailer my Jeep to the trails more often than not, but it would be nice to know I could drive it down the highway and not have the Jeep be out of control! Would these be okay in the front and back, or is one end versus the other better? Or not at all? I plan to run 36s and the 4-inch Rubicon Express springs in front and back, spring under.
Jake
via e-mail
Pete Trasborg runs them on one of his YJs. According to Trasborg, they do add droop and offer no problems on highway, even with no track bar and stock YJ springs. However, Trasborg says when wheeling them he has never got them to drop out even once. On the lift at the shop, they add droop, but for the wheeling his YJ has seen, nope.
The company makes top notch stuff, so by all means don't have any hesitation calling them up. It's just that I don't really go in for the gimmicky things like buggy springs, Revolver shackles, and so on.
If you run a good spring (which those Rubicon Express springs are), you really shouldn't need anything like that. It's been my experience that as long as you're running at least a rear locker you don't need tons of insane axle flex. You'll sometimes hang a tire in the air, but your vehicle will be more stable and predictable with fewer handling and wheeling quirks than if your rig can drive to the top of some ramp without lifting a tire.
The 36s are going to be big, but completely within the realm of possibility on a flattie. You'll wind up cutting some rear fender material and you're going to need to cut out the factory inner rear fender reinforcement behind the rear tire, but you'll be able to stuff the tires without resorting to the "competition cut" that lots of Jeep guys emulate. Again, just my opinion but I always prefer the look of a Jeep that hasn't had the rear of the tub completely chopped away.
Hierarchies
A huge topic in the Jeep world and on web forums everywhere is the debate over rear axles. We all know the Dana 35 is weak, but there are no specifications anywhere that compare the following axles: Dana 35, Superior Super 35, Dana 44, Ford 8.8
This topic has proven to be a huge frustration to many and I think that some scientific destructive testing of those models would really be interesting to a great deal of people. I think you should run a story on this!
Greg Volkman
Travis AFB, California
This is like flogging a dead horse, but here's how they stack up:
Dana 35 w/Superior 30-spline: Shafts stronger than stock Dana 44 (better alloy) but ring and pinion still weaker than a Dana 44
Ford 8.8: On par or slightly weaker than Dana 44 (C-clip type 8.8 axles especially)
Dana 44: Strongest. Upgrade to 33-spline shafts and it's able to handle over 350hp and/or 37 inch tires with good success
While destructive testing would be fun, we don't have the capacity in-house and there's plenty of data generated by ARB and other companies who have done destructive testing to back up what I've just written.
Got a tech question you're just itching to get answered? Send it on in to Jp magazine, Your Jeep, 831 S. Douglas St., El Segundo, CA 90245, or e-mail christian.hazel@jpmagazine.com.