With all the fuss over aftermarket trinkets and flash components that make your Jeep look and wheel better, it's easy to overlook the simple maintenance necessary to keep your Jeep safe. Case in point is our recent '68 J2000 Gladiator purchase. After dragging it home, we discovered the steering-knuckle kingpins were in horrible shape. The same principles apply to all early '40s to early '70s closed-knuckle Jeep front axles, but you want to make sure the knuckle cavity is full of grease to keep the kingpin bearings and axleshaft joints lubed and that you've got the right kingpin preload for safe tracking and resistance to death wobble. Here's what we found in our axle.
Just about every closed-knuckle Jeep will have a 6-bolt external body hubs. Remove the dial cap and the stub shaft snap ring. Then you can remove the hub body bolts and the hub. Early axles with drive flanges will have a nut that threads onto the end of the stub shaft. Remove the flange cap, remove the nut, and then unbolt the flanges.
Our knuckle cavity was dry as a bone. Lubrication preferences range from straight 90W to a pudding mixture of axle grease mixed with 90W to straight axle grease. Regardless, the cavity should be filled with more than rust and bearing fragments. We normally run good-quality axle grease with no 90W mixed in. It has worked well for us.
With the spindle nuts removed, you can take off the hub/drum assembly (early models). Later models allow the drum to be removed without removing the hub. Once it's stripped down to the spindle, you need to remove the backing plate. There's no need to remove the brake shoes and hardware. Pry back the locking tabs and then remove the 6-spindle bolts.
The spindle can be dislodged with a firm whack from a rubber or soft-faced, dead-blow hammer and the axleshaft assembly can be removed. Don't forget to pop off the steering linkage tie rods and remove the seal retainers and grease seals from the back of the knuckles if you plan on going into the kingpins.
Dana 44s have flex hoses directly to the brake cylinder, so you can just remove the hose retainer clip and set the whole backing plate/brake assembly aside. Dana 25 and Dana 27 axles require the removal of the S-shaped hard line from the brake cylinder so the backing plate can be removed. Don't forget to bleed the brakes after reassembling.
Pop off the upper and lower kingpins and shims and keep them in order from top to bottom and left to right. Early Dana 25 knuckles used different upper and lower kingpins. Dana 27 and Dana 44 used the same kingpin on the upper and lower. The shim packs determine bearing preload. With a fish scale, remove or add shims as needed to the top kingpin (early D25s shim the upper and lower kingpins) until the scale indicates 12-14 pounds of steady pull to turn the knuckle.
Although our kingpins, races, and bearings on our '68 Dana 44 were hammered, Cappa had an extra set leftover from a J-Truck Dana 44 that was in good condition. We tapped in the good, used races, installed the bearings, and dropped on the new kingpins.
After setting the bearing preload, we slid in the axleshaft assembly, packed the knuckle with grease, and reinstalled our brake hardware. With some new brake shoes from the local parts store, we were ready to roll down the road safely with 33s.