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JB Rotation Plate

KIT #15-1102 -- $250.00

Must specify input spline count:

The purpose of the new clocking ring offered by JB Conversions, Inc. is to allow the Dana 300 to be rotated into positions more conducive to the use of flat skid plates, multilink suspensions, etc. There are a few "clocking rings" available through various aftermarket sources which accommodate this task. We have designed what we consider to be the best kit on the market. The following summary illustrates some of the highlights of our design.

Once installed, the new face plate offers a clean appearance with a varying degree of clocking points positioned at 7.5 degree intervals. You will also notice a new input gear extending forward with an internal spline. The standard spline for Jeep transmission applications is 23. We can accommodate GM spline counts with the optional input gear combinations for use with the clocking plate.

KIT COMPONENTS

The bill of material for the complete kit includes the new billet clocking plate, 6 allen cap screws, extended length input gear and 6 new "interference fit" studs.

Kit Parts

The 6 new studs included in the kit are made with a special interference fit thus allowing the nut to be easily removed during transfer case removal without the stud backing out first.

Dana 300 Clocking Plate

DESIGN ADVANTAGES

The design we have chosen to produce is one that retains maximum strength by incorporating the bearing retainer into the design of the clocking plate. During installation of the kit, the stock Dana retainer is eliminated. With this feature, our clocking plate retains a thick cross-section throughout the indexing area of the piece. This allows us to manufacture the plate from billet aluminum. An early design idea was to use a "ring" as shown in the comparison photo below however the ring design did not yield the thick cross-section desired.

Dana 300 Clocking PlateDana 300 Clocking Plate

The new input gear undergoes a precision grinding process over an extended length beyond the stock specification. This allows the use of a conventional oil seal and also the original open ball bearing resulting in superior lubrication.

Dana 300 Clocking Plate

The new input gear is also longer than stock. This allows tranny-to-transfer case spline engagement specifications to remain intact eliminating any chance of twisting the transmission shaft spline due to poor engagement.

One method we have seen for rotating the Dana 300 is to drill a new hole rotation into the face of the Dana 300 case. The following photo reveals the internal casting shape, which allows for a casting "boss" where each stock bolt hole is located. The thicker material created by these boss areas is key to supplying the thread strength required to make a strong anchor point for the mounting bolts. When additional holes are drilled into the case, the new hole locations do not provide this thicker material therefore a weaker thread engagement is created. We do not recommend redrilling the stock case for purposes of rotating the case.

Dana 300 Clocking Plate

Dana 300 Clocking Plate


INSTALLATION INSTRUCTIONS

1) Drain the oil from the Dana 300.
2) Remove the 8 allen (or torx) cap screws from the aluminum bearing retainer and carefully separate and remove the retainer from the Dana 300 case.

Dana 300 Clocking Plate

3) Remove the retaining ring from the input shaft.

Dana 300 Clocking Plate

4) Remove the helical gear from the input shaft. Usually, this gear is fairly tight therefore it may have to be removed with a drift or a press (preferred). The original seal may be pushed out during this step however it will not be reused.

Dana 300 Clocking Plate

5) Remove the retaining ring from the original bearing retainer.

Dana 300 Clocking Plate

6) Remove the original bearing from the retainer using a press. Usually this bearing can be gently knocked out of the retainer with a wooden drift.

Dana 300 Clocking Plate

7) Clean the gear, bearing, and retaining ring with solvent or brake cleaner.
8) Install the original bearing (removed in step 6) and retaining ring into the new clocking plate.

Dana 300 Clocking PlateDana 300 Clocking Plate

9) Place the shims on the new input gear (use grease to hold them in place) and press the input gear into the bearing.

Dana 300 Clocking Plate

10) The gear should be pushed or pressed into place against the bearing.

Dana 300 Clocking Plate

11) Install the input drive gear onto the spline of the input shaft followed by the retaining ring.

Dana 300 Clocking PlateDana 300 Clocking Plate

12) Using a gap gauge, check for 0.00"-0.003" clearance below the retaining ring. If clearance is insufficient, adjust shims as necessary. Add or subtract shims if necessary.

Dana 300 Clocking Plate

13) Install the new oil seal using a press or seal driver.

Dana 300 Clocking Plate

14) Clean the gasket face of the Dana 300 and apply a very thin bead of black RTV to the case.

Dana 300 Clocking Plate

15) Install the clocking plate and secure with the 3/8" bolts supplied in the kit. Use a small amount of RTV on the threads of the 3/8" bolts to prevent oil leaks.

Dana 300 Clocking Plate