[Rollbar]

Earlier Jeeps typically use U-bolt yokes and information has not been gathered yet for '97+ Wranglers. This upgrade will also work for Cherokees and Grand Cherokees, but you must determine if you have a Dana 35c, Dana 44, or Chrysler rear end.


Dana 35C Rear Axle & others
Two pinion yokes were used on the YJ's D35C rear axle. Through 1993, Spicer part #2-4-6901-1X was utilized. This yoke uses 1310 series U-joints measuring 3 7/32" cap-to-cap. In 1994 and 1995, a larger pinion yoke part #2-4-7631-1 was employed which uses 1330 series U-joints measuring 3 5/8" cap-to-cap.

Both of these yokes can be upgraded to a U- bolt setup by drilling out the existing holes with a 5/16" drill bit and installing U-bolt part #2-94-58X. You may find that a 21/64" drill bit is necessary, but the 5/16" should work fine.

AMC Model 20 Rear Axle
The same trick can be performed on the AMC 20 pinion yoke part #2-4-3741-1. This yoke may be drilled out to accept U-bolt part #2-94-58X.


Dana 30 Front Axle (CJ)
Due to the number of different yokes installed on the D30, it's very difficult to state which yokes accept which type of conversion. Generally speaking, pre- and early-80s CJs already have U-bolt setups, while later Jeeps employed strap-and-bolt connections. For conversion from strap-and-bolt to U-bolts, you'll just have to eyeball it. If there is room for a nut behind the yoke, you can drill it. If not, you probably need to replace the yoke with Spicer part #2-4-8091X and use U-bolt part #2-94-28X.

Dana 30 Front Axle (YJ)
There is insufficient room behind the stock yoke for the U-bolt nut on the YJ front Dana 30 pinion yoke. The entire yoke must be replaced with Spicer yoke #2-4-8091X and U-bolt kit #2-94-28X to upgrade to a U-bolt connection.


Transfer Case Yokes
The NP231 front output yoke and both D300 output yokes do not have sufficient room behind the stock yoke for the U-bolt nut. The front output on the NP231 uses the same parts and procedure as the Dana 300.


*The Dana 300 was used in CJs from 1980 until 1986 is probably the best all around transfer available in the CJ. It features a heavy duty cast iron case, gear drive, and a respectable 2.62:1 low. It shares a flexible input pattern that is used with many of the modern transfer cases of today and it's helical cut gears operate quietly. There are always ways of improving a good thing though, fortunately for the Dana 300, the improvement is easy and fairly inexpensive.

The only mistake Jeep made putting the Dana 300 in the CJ was by changing from U-bolt yokes used on the Dana 20 to strap type yokes. The straps tend to loosen and break easier than the U-bolt yokes. Converting the Dana 300 to U-bolt yokes doesn't cost too much and it requires only a few common tools. The tools required include:

1/4" 12 pt. socket and socket wrench to remove strap bolts.
1 1/8" socket and socket wrench to turn it. This is needed to remove and replace the yoke retaining nut.
18" pipe wrench or other wrench large enough to clamp on to the yoke.
1/2" open end wrench to tighten U-bolts.
Torque wrench to tighten retaining nut.

I've heard that the yokes from a Dana 20 will fit on the Dana 300, so if you have a Dana 20 with decent U-bolt yokes or if you can find one in the core pile at your local yard, you might save some money. To replace a bad yoke that had been damaged and no longer held the u-joint firmly causing some driveline vibration. Order two yokes (Spicer part 2-4-2461X) and two U-bolt kits (Spicer part 2-94-28X). The flange protecting the seal maybe too large. Hamer it off and used the flange from the old yoke. There probably is a part that will perfectly replace the front yoke, but I do not know the part number.

Here is the step-by-step process of replacing the yokes:

Block tires so your Jeep doesn't roll away.
Remove the driveshafts with 1/4"/8MM 12 pt. socket
Hold the old yoke with the pipe wrench while removing the yoke retaining nut with 1 1/8" socket.
Remove old yoke and slide on new yoke.
Hold new yoke with pipe wrench while tightening yoke retaining nut to 120 ft/lbs (162 N/M)
Reinstall drive shafts with U-bolts and tighten with 1/2" wrench.

The yoke retaining nuts/washers should technically be replaced since they are locking nuts.

[92SquareEye]

Rollbar, on Sep 28 2007, 06:29 PM, said:

Dana 35C Rear Axle & others
Two pinion yokes were used on the YJ's D35C rear axle. Through 1993, Spicer part #2-4-6901-1X was utilized. This yoke uses 1310 series U-joints measuring 3 7/32" cap-to-cap. In 1994 and 1995, a larger pinion yoke part #2-4-7631-1 was employed which uses 1330 series U-joints measuring 3 5/8" cap-to-cap.

Both of these yokes can be upgraded to a U- bolt setup by drilling out the existing holes with a 5/16" drill bit and installing U-bolt part #2-94-58X. You may find that a 21/64" drill bit is necessary, but the 5/16" should work fine.

do you (or anyone else) know if the yokes can be changed over? we snapped a u-joint that cracked the yoke when it went. i was gonna go with a u-bolt style replacement, but can i "upgrade" to the larger 1330 series from the original 1310?

it's the original d35.

thanks

-dave

ps - i'm going out to remove the yoke now. i can give more as to sizes and spline counts after i get it out.

[NonStop]

Is there room behind the yoke for U bolts when the 231 gets a SYE? Anyone out there with one feel like taking some pictures?
Tom Wood Info

[92SquareEye]

Nonstop, on May 11 2008, 09:47 PM, said:

Is there room behind the yoke for U bolts when the 231 gets a SYE? Anyone out there with one feel like taking some pictures?
Tom Wood Info

i'll see what i can do. the pinion yoke came out surprisingly easy. i think i'm just going to replace the stock yoke for now until we decide what to do for axles. this time, i think i'll opt for some beefier ujoints. the one that went were the cheepies from a-zone. when my favorite shade tree wrench monkey put them in, i knew they would need replaced soon.

-dave