New Rear diff cover and fluid change

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MTF

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It doesn’t matter whether you have a Gen 1 or a Gen 2 as the rear ends are the same. Best differential oil you can run on these trucks.
Gen 1's require 75W-140

Jennies require 75W-85

Haven't looked into what they have changed in the rear to have this difference.
 
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Deleted member 17706

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Gen 1's require 75W-140

Jennies require 75W-85

Haven't looked into what they have changed in the rear to have this difference.

Ford’s recommendation for the Gen 1 was not originally 75W-140. If I recall you posted a link with a chart last year or so with Ford’s fluid specificities. But originally, that was not the weight recommended by Ford. Guys were running the 75W-140 for superior protection off-road, towing, SC applications, everyday driving, and so on. The Gen 2 is no different and will benefit from it as well. My Gen 2 will be running it (just like the other trucks in my fleet).
 

MTF

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Ford’s recommendation for the Gen 1 was not originally 75W-140. If I recall you posted a link with a chart last year or so with Ford’s fluid specificities. But originally, that was not the weight recommended by Ford. Guys were running the 75W-140 for superior protection off-road, towing, SC applications, everyday driving, and so on. The Gen 2 is no different and will benefit from it as well. My Gen 2 will be running it (just like the other trucks in my fleet).
In my 2010 1/2 manual it states 75W-140 for the Rear(E)
And in the chart you'll see the dot which is 75W-140 for all the Gen 1's
The front diff is a diamond which is 80W-90 for the Gen 1's
Axle Fluids.JPG
Axle Fulids p.2.JPG
 
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The only reason I can think of for the weight change if they didn't change something in the rear on the Gen 2's is, to get a little more mpg for the CAFE numbers.

Yea, that and the fact Ford wanted to insure the Jenny got better fuel economy than the Gen 1. LOL hence why they have c range tires, auto stop, and so on.
 

Wheelz96

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I just replaced the diff cover with the Ford Performance. In hindsight, I should have opted for the Spicer. I ended up using a lube locker gasket and had good experience in the past. No more messy RTV silicone! Now I can change out diff oil in a breeze. I also replaced the rear pinion seal that was leaking and that's why I originally bought the diff cover. Certainly could have saved some coin if I got below the truck sooner but it sure does look good!

Edit: Do yourself a favor and replace bolts that come with Ford diff cover. They are garbage and start to strip at around 26 Ft lbs...
Diff Cover.PNG
 

Wfo

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I just replaced the diff cover with the Ford Performance. In hindsight, I should have opted for the Spicer. I ended up using a lube locker gasket and had good experience in the past. No more messy RTV silicone! Now I can change out diff oil in a breeze. I also replaced the rear pinion seal that was leaking and that's why I originally bought the diff cover. Certainly could have saved some coin if I got below the truck sooner but it sure does look good!

Edit: Do yourself a favor and replace bolts that come with Ford diff cover. They are garbage and start to strip at around 26 Ft lbs...
View attachment 138970
Had same problem with the spicer bolts, think they are the same.
 
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