jeep Dana Spicer 18 - gear - Photo 9300906

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The 3/4-inch and 1 1/8-inch Spicer 18 transfer cases use caged bearings. They only need to be lightly lubricated with grease or gear oil prior to installation. The 1 1/4-inch transfer cases have 48 independent rollers that need to be held in place with thick grease prior to assembly.

154 0706 01 z+jeep+front passenger view road

154 0706 01 z+jeep+front passenger view road

On the left is a 1 1/8-inch intermediate shaft that we let go way past its prime. It's an import unit that we managed to squeeze about 6,000 miles from before the whole transfer case went bang. The bearings had worn out of the cages and were in very sad shape. The shaft on the right is from the same manufacturer, and after 2,000 miles of use, it's showing unacceptable wear.

Once the bearings and the shaft wear, the intermediate gear will no longer run parallel to the rest of the gears. The gears won't mesh properly and even more noise will emit from the transfer case until all of the gears start chucking teeth like a 98-pound hockey player.

The 3/4-inch and 1 1/8-inch Spicer 18 transfer cases use caged bearings. They only need to be lightly lubricated with grease or gear oil prior to installation. The 1 1/4-inch transfer cases have 48 independent rollers that need to be held in place with thick grease prior to assembly.

Here's another low-buck jobbie-check out the dents in the shaft. Is someone making these things out of rebar? We've had poor-quality shafts damaged in shipping, so how are they supposed to survive inside a transfer case?

The Novak shafts come with bearings, thrust washers, some other small parts, and are several times harder than the import junk we're used to. A harder shaft will last longer.

All of the Novak shafts have O-rings on both ends to eliminate oil leaks. Smear grease on the O-rings to prevent them from being cut or chewed up during installation.

Grease the thrust-washer mating surfaces in the transfer case to hold the thrust washers in place. You can also grease the bores so the O-rings slide in easily.

Once you have the washers in place, you can use the new shaft and an old one to keep them there while installing the intermediate gear.

Here's another sweet bonus. Most aftermarket intermediate shafts are too long, and they interfere with the transfer case adapter. This often causes oil leaks unless you grind the adapter for clearance. Novak makes the shafts just long enough to sit flush with the case.