YOKE UPGRADES

Author: Rick Boiros

Running 10 rated trails, weak links are bound to show up! A common break that can be easily modified is replacing u-joint retaining 'straps' with 'u-bolt' style fasteners used in pre-1980 Jeeps.

Straps are common on 80-86 CJ and YJ, Wrangler, axles and transfer cases as well. The straps are fastened with very small 1/4-28 bolts, often with a 12 point head that is difficult to get a wrench on. The straps themselves stretch over time and the bolts can easily break or loose. The result is at least a dropped driveshaft or lost u-joint cap, at worst, broken screws that are difficult or impossible to remove. The permanent solution is a modified or swapped yoke for the axle and/or transfercase.

DANA 300 and NP 231 (front only) Transfercase upgrade: Both yokes and straps (Front and rear on the dana300) can be replaced with Dana model 20 yokes (late 70's cases have the proper spline count) or new parts can be purchased from a Spicer dealer. The yokes are Spicer PN 2-4-2461X and U-bolt kit 2-94-28X. A puller may be required to remove the yokes and the nuts must be re-torqued to 120 Ft.lb. Do not overtighten the new u-bolts or u-joint bearing damage can result. Note: these yokes have a large flange or shield on them that needs to be removed for clearance, These part numbers also works on Dana 44 front or rear axles.

DANA 30 Front axle (1980+CJ and YJ) : Spicer PN 2-4-8091X yoke and U-bolt kit PN 2-94-28X will replace the strap style yokes with u-bolt yokes.

AMC-20 (1981-1986 CJ) ; DANA 35 Rear axle (1987-1995 YJ) : These yokes can upgraded to u-bolts by drilling out the existing 1/4" threads with a 5/16" drill bit. U-bolt kit Spicer PN 2-94-58X can then be used in place of straps.

Some notes on u-joints, particularly axle universal joints: Spicer and Neapco parts, from experience are among the best. Stay away from no-name or parts store cheapy u-joints. They WILL break, particularly in CJ front model 30 applications. Also, do not use axle joints that have the grease fitting in the u-joint cross body. A grease fitting can be specified in the u-joint cap, this style is considerably stronger since less material is removed for grease passages.

These simple fixes will increase overall strength and reliability considerably.

See you on the trail, hopefully not laying in the mud under your 4x4!

Rick

Contributors: Dan Barbieri, Terry Howe, Tom Woods at Six States Distributors.

Parts breakers that warranted the article: Scott Hatch and Mark Franklin.

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