Rear Diff Cover

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digithead

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I need some schooling. I thought all the rear end diffs used a cover and gasket. Mine looks welded all around the outside? WTF?

rearend.JPG

 
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Our cars differential have the covers in the front. The rear has no cover. Actually, we have whats called a third member so when you disassemble the front it comes out with the gears attached.

1971 M-code Mach 1

 

digithead

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oh ok, thanks. Yea, I see all the guts pull out from the front only. I guess I assumed even like that the rear would also be a cover too so you can look in and inspect it etc etc. Thanks.

 
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The differential you refer to with the cover on the rear use to be commonly called a Spicer type rear. Ford used both depending on the use of the vehicle. It is most people's opinion that the removable center section style like the Ford 8" & 9" is a better and stronger design. All heavy trucks use that style. It is easier to work on. You have to pull the cover plate off the Spicer type and remove the pinion shaft and push the axles in and remove the C clip to get the axles out. With the removable center section you simply remove the brake drum and take the 4 nuts off that retain the axle and remove. Pretty much all cars have the Spicer type today that are rear wheel drive they cost less to build is the driving factor. If you have ever been at the drag strip and see a GM car with the stock 12 bolt rear break an axle you will know why most racers change to the Ford 9". When the axle breaks there is nothing to hold it in and the tire wheel comes out and tears up the quarter panel and sometimes the car flips. They do make kits to retain them but most just switch to the Ford rear. In NASCAR for many years all makes ran the Ford 9" because it was so much better and easy to change the center section to change the gear ratio.

Looking at the back of you rear it is a 9" the 8" has a smooth round rear the 9" has the one side bubbled out. Nothing to really inspect in the rear unless it is making a noise then it is usually a pinion bearing or incorrectly adjusted gear mesh.

 

digithead

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The differential you refer to with the cover on the rear use to be commonly called a Spicer type rear. Ford used both depending on the use of the vehicle. It is most people's opinion that the removable center section style like the Ford 8" & 9" is a better and stronger design. All heavy trucks use that style. It is easier to work on. You have to pull the cover plate off the Spicer type and remove the pinion shaft and push the axles in and remove the C clip to get the axles out. With the removable center section you simply remove the brake drum and take the 4 nuts off that retain the axle and remove. Pretty much all cars have the Spicer type today that are rear wheel drive they cost less to build is the driving factor. If you have ever been at the drag strip and see a GM car with the stock 12 bolt rear break an axle you will know why most racers change to the Ford 9". When the axle breaks there is nothing to hold it in and the tire wheel comes out and tears up the quarter panel and sometimes the car flips. They do make kits to retain them but most just switch to the Ford rear. In NASCAR for many years all makes ran the Ford 9" because it was so much better and easy to change the center section to change the gear ratio.

Looking at the back of you rear it is a 9" the 8" has a smooth round rear the 9" has the one side bubbled out. Nothing to really inspect in the rear unless it is making a noise then it is usually a pinion bearing or incorrectly adjusted gear mesh.
Cool. THanks for the lesson!

 
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