Readers Tech Questions Answered!
Q In the Apr. ’11 issue in BDS Betters BluFerd you mention Mickey Thompson aluminum wheels with steel inserts in the lug seat. What specific rim is that? Do they do that with other rims? (I drive an F-350).I can’t seem to find it on their website. The reason I ask is up here on the salt-laden roads of Michigan the lug nuts seem to weld themselves to aluminum rims. Any info would help.
AThe Classic II and Classic Lock wheels have steel inserts, and Mickey has them in all bolt patterns (Mickey Thompson Performance Tires & Wheels, 330.928.9092, www.mickeythompsontires.com). The black painted wheels do not have steel inserts. However, I would recommend antiseize on your wheel lug nuts to help with removing them after inclement weather.
Q I purchased an ’80 CJ-7 (early model with narrow-track axles) with an inline 258 and a four speed. I had the transmission and transfer case rebuilt recently, so they’re tight. My plans are to park the Jeep in the garage for the winter and pull the 258 and swap to a 258 crate motor with throttle body fuel injection, then swap axles from a frame I bought. My plans are to build a Jeep with 35-inch off-road tires (eventually with beadlock rims) that I can take out on the trail and tackle most of what I want, but I’m not planning on getting into anything over-the-top.
The axles are the wide-track axles, with new brakes, one-piece axles, and a 3-inch lift kit. I think it should be a fairly simple job to swap the axles onto my Jeep. (Spring mount points measured identically between frames.) The rear axle also has an ARB Air Locker installed that was never used. The AMC 20 axle has gotten a bad rap over the years, and everyone seems to have a different opinion, and since the AMC 20 axle is easily accessible, I would like to beef it up. I have nice MIG and TIG welders and some welding experience.
What steps should I take to ensure that the axle is solid to do what I want? Trusses? Weld the tubes to the diff housing? Properly hardened, would this axle serve me well for my future endeavors?
A Your axle seems properly built so far for 35s. The AMC 20 rear has an 878-inch-diameter ring gear and 114-inch 29-spline axleshafts. I would add a truss on the top (nothing extravagant) and go. I see lots of overbuilt heavy trusses. I think if you took a single piece of platesay, 316- or 14-inchand cut it out to follow the silhouette of the axle from flange to flange and then topped it with a small 1-inch strip, you’ll be set. Imagine an I-beam where the axletubes are the bottom of the I and the 1-inch strip is the top of the I.
I don’t think you need to weld the tubes to the cast centersection unless you know how to weld cast to steel with nickel rod. I would consider a gusset from the pinion casting up to the truss, welded to the truss, but just touching the pinion casting as added insurance against the tubes twisting in the housing under hard acceleration, climbing, or aggressive wheeling when the pinion wants to roll up. Don’t forget to leave holes for the U-bolts.
Now, if you are planning on going spring-over, you will need to adjust the design to allow for the relocated springs.