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Mag-Hytec Rear Differential Cover*

Old 09-24-2009, 06:44 PM
wildcat's Avatar
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Default Mag-Hytec Rear Differential Cover*

Recently, I purchased a Mag-Hytec Rear Differential cover and Deep Transmission pan from Chris Brahs (Cbrahs) owner of HDR Diesel

Chris is a GREAT guy to deal with, and I am proud to consider him a personal friend now.
If you need parts and someone you can trust, give him a call. I'll stake my reputation you will be satisfied!
On to the modification!!

This by far is one of the easiest mods I have done to my truck. I was reluctant at first to install the Mag-Hytec differential cover, because usually when it comes time to service the differentials in my rigs, I end up completely covered in smelly gear oil. I suspect future gear oil changes to be even easier and less messy than this one!

First on the agenda is removal of the old cover. I used a 1/2" deep socket and ratchet for this. I started at the top and worked my way down both sides.

When I got down to the last 3 bolts, The factory reusable gasket allowed somewhat controlled draining of the fluid, Which actually didn't look too bad for 16K miles of break in.

Here's a pic of the differential cover removed... Those familiar with the GM 14 bolt might see some similarity here.

The old cover uses 14 bolts for attatchment. The new cover uses 12, deleting the upper and lower bolts for drain and fill considerations. Also, the cover comes with an O-Ring seal instead of a gasket. the sealing surfaces do not match exactly, so it is advisable to clean up the entire cover mounting surface to allow the O-ring to do it's job. The only places it really mis matches are top and bottom, but why take a chance. I used a wire wheel to clean my surface, making sure that the contact side of the wheel would carry debris away from the differential.

Pic of the surface all cleaned up.

Installation of the new cover is pretty straightforward. Follow the included instructions for lubricating the O-ring with gear lube, and tightening information.

After installation pic

Note: This cover DOUBLES the capacity of your rear Differential. You will use about 2 GALLONS of Gear lube.
All that is left is to fill it as specified in the included instructions with factory approved Synthetic 75-140 and friction modifier.
This is where things got really easy. I had to lower my spare tire, but this allowed me to place a funnel into the fill port at the top of the cover, and pour 2 gallons of fluid (Actually 7.5 Qts.) right from the gallon containers directly into the differential in record time with no mess!! No more fighting messy quart squeeze bottles, or gear oil pumps, etc! Checking the fluid level is super easy as well and creates no mess. I'm actually considering dropping coin on a front cover to further simplify my gear lube service on my truck.

Special Thanks to Chris at HDR Diesel!

Any questions or comments, feel free to post them up!
Old 09-27-2009, 12:43 AM
tower_ofpower's Avatar
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royal purple shouldnt need the friction modifier... i believe it says it right on the bottle; i'd go down to the basement and look at a bottle but i'm feeling exceptionally lazy... personally i like royal purple and feel its some good stuff not too many people talk about it really; but then again they're still catching on...

---AutoMerged DoublePost---

and the mag-hytec product line is pretty much amazing... they make some awesome looking and 100% functional products

Last edited by tower_ofpower; 09-27-2009 at 12:43 AM. Reason: Automerged Doublepost
Old 01-14-2011, 12:34 AM
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Mag-Hytec heavy-duty Differential Covers provide increased lubricant and cooling capacity for hard working recreational and service vehicles.All Mag-Hytec covers come with a suspended magnet that acts as a filter to contain these particles, keeping the fluid cleaner and extending component life.
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