Dana 300 - 32 Spline Rear Output Shaft Upgrade

Kit layout

This kit provides features not offered by any other competing shaft kit.

Part #2308-1942 -- $450.00 (w/1310 CV Yoke)

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Part #2308-1983 -- $450.00 (w/1310 Non CV Yoke)

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Part #2308-1946 -- $450.00 (w/1350 Non CV Yoke)

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Part #2308-1966 -- $475.00 (w/1350 Rear Output Flange)

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Kit Components:

  • Aluminum bearing housing
  • 32 spline rear output shaft
  • Aluminum seal retainer
  • National oil seal #473239
  • (6) Allen cap screws 5/16" x .75"
  • (5) Allen cap screws 3/8" x 1.25"
  • CV yoke # 2-4-5341
  • 7/8" x 20 Lock nut - Chrysler #4167924
  • 7/8" x 20 Shim Setup nut
  • Rubber star washer seal - Chrysler #4210973
  • Speedometer gear - Chrysler #4338996
  • Snap ring - Chrysler #4338997
  • Large Spacer ring
  • Small Spacer ring
  • Needle bearing
  • Tapered roller bearing #30207 (cup & cone)
  • Tapered roller bearing #26822, #26885 (cup & cone)
  • Shim set
  • Vent fitting 1/8" NPT x 5/16"

Comparison

 

Comparison

 

The original Dana 300 rear output shaft is not as strong as it could be. 4-to-1 gears, larger tires, and V8 engines have been responsible for many OEM shaft failures on stock Dana 300's. Other aftermarket companies have put together shaft kits to address this problem however we feel that our kit is beyond compare. This kit is offered by our company as a compliment to the full line of JB Conversions, Inc. products for the Dana 300.

Kit layout

The kit is packaged as shown above.

The Dana 300 Big Shaft kit contains several features not available from kits made by competitors. The housing is heat treated aluminum with a very thick top section. A 6-bolt mounting flange with two 3/8" dowel pin holes has been integrated into each aluminum housing. The top section of the housing has been especially designed to accommodate a parking brake with this 6-bolt flange face. If a parking brake is not used, a billet cap and seal is supplied with the kit.

Notice the beefed up flange area of the casting (Fig.1,2).

Kit layout

FIG: 1

Kit layout

FIG: 2

The stock Dana bearing housing is shown on the left (Fig.3). There is a significant size difference between stock and the Big Shaft Kit. The rear tapered roller bearing is much larger in the new kit compared to stock.

Kit layout

FIG: 3

The housing on the left is made of nodular iron (Fig.4). This variation of the Big Shaft Kit is being considered for production. If you prefer an iron housing let us know via email.

Kit layout

FIG: 4

The rear flange provisions integrated into the rear bearing housing provide the optimum mounting system for a parking brake (Fig.5). As seen in the previous photos, a 6-bolt mounting face with two 3/8" dowel pin holes is provided to make a parking brake bracket secure without the need for exterior bracing. JB Conversions does not manufacture a parking brake kit as shown in Figure 5.

Kit layout

FIG: 5

The output shaft in this kit is another example of precision machining. The new shaft is fully ground in the non-splined areas to provide a perfect fit for the tapered roller bearings. The shaft is made from 8620 heat treated alloy and features the heavy duty 32 spline end common to the NP205 transfer case. Notice the size difference when compared to the stock Dana shaft on the left (Fig.6).

Kit layout

FIG: 6

Another feature which sets this kit apart from the rest is the the ability to adjust shaft end play or bearing preload. A shim pack is included in each kit which allows perfect adjustment of end play. An extra shim pack is supplied in the event of a future rebuild or bearing change (Fig.7).

Kit layout

FIG: 7

NOTE: Other kits on the market are furnished with pre-machined thrust washers to achieve correct end play. We don't think this is the best design. The competitors thrust washers are machined to provide specific shaft end play based on the specific bearing installed in their kit as it leaves their facility. With this type of thrust washer, there is no way to allow for slight size differences in bearing size in the event that your Dana 300 is ever freshened up with new bearings. We have seen slight variations between bearings of different brands and also within the same manufacturer.

 

Additional Info

Installation Instructions

Install Instructions

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