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RockCrusher Dana30 Differential Cover

A while back it was very clear to me that undercarriage protection is required while climbing around on the trail. There has been many times when a good wack to the rear diff was heard from inside the cab. I purchased a Dana35 RockCrusher a few months back and the Dana30s have been on back order a while. Dave with Northridge4x4 contacted me to let me know the Dana30s where available. So naturally I told them to send me the front to complete my pair.

Tools: Time:
14mm hex bit
1/2 socket, driver and extension
2.25 Quarts of lube
Spray paint or paint 		30-minutes to 2hours for paint

Just like the Dana35 and the Dana44 the fill plugs have been lifted and man they weigh a bit more as well.. Below under the pictures there are some subtle differences noted. This write-up/review really concentrates on the differences of the stock vs the rockcrusher. For a complete howto on changing your diff fluid give this a review. "Dana Axle Differential Fluid Change". Written by kizer, if you have any questions or comments about this install visit

 


First off use a can of primer to coat the cover.

I used two coats of Rustoleum flat black spray paint to complete the finish.

Use a rag and some brake cleaner to spray the inside of the cover. As you can see from the white rag there is a lot of suface residue on the inside of the cover. Im guessing its either a protectant or simply a bi-product of casting the cover.

Before you remove your stock cover make sure you have a way to remove the RockCrusher fill plug as well a way to tighten it.

I took a bolt with a 14mm head on it and bent it into a 90degree angle to act as a wrench.

Use a 1/2 socket to remove the factory bolts.

As you remove each bolt you will end up removing the gear tag on the left side of your axle Store it in a safe place just incase you decide to well show it to somebody. =)

The easiest way to drain your diif is to remove all of the bolts with the exception of the top one. Loosen the top one aproximately halfway so when you crack the cover you have a way to hold it while the old lube drips out.

Some like to use a screw driver or a chisel to pry the cover from the axle. I like to use a rubber mallet and give it a good wack at an angle. If it doesn't work break out the screw driver or the chisel.

Keep in mind this is what your trying to protect. When/If you smack your stock cover hard enough it will leak When it leaks your done.

Here is a few comparison shots of the stock vs RockCrusher.

The RockCrusher is aproximately 1/2 inch taller

Just incase you ask this is what the stock cover looks like behind the Tie-rod on a TJ

Heres how the RockCrusher looks behind the Tie-rod on a TJ

Downward view of the Stock cover on the left and the RockCrusher on the right.

Stock cover weighs in at 3lbs
RockCrusher weighs in at 8lbs

Both above weights are aproximate. I stood on a scale using my weight as a control and then held each one subtracting the difference to determine the actuall weight of each.

Stock cover is just shy of 3/6ths of an inch.

RockCrusher is 1/4 of an inch thick.

Top view of both.

Look how high the fill plug on the RockCrusher is compaired to the Stock cover.

Need a better point of view?

Upon a crude measurement the RockCrusher the fill plug is aproximately 2 1/4 inches higher.

After you apply your RTV and begin installing the cover make sure you insert each bolt before you start tightening them down. The cover is machined very titght and their isn't much room to wiggle the cover.

Use a 1/2 deep socket to tighten each bolt in a clockwise direction. When you reach the two bolts on the very right you will have to use a wrench becasuse a socket just doesn't fit.

Use a torque wrench and tighten each bolt to 30 flbs. I more or less faked the two on the right because I couldn't get a socket on them.

Rememember that new wrench you built or at least I did? I filled up the RockCrusher cover with 80/90. The FSM says to tighten the fill plug to 25 flbs.

Stock 1.50 quarts
RockCrusher 2.25 quarts

Heres a head one of the Stock cover.

Heres a head on of the RockCrusher

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