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rear end fluid

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Old Apr 25, 2004 | 09:01 AM
  #1  
snakebit's Avatar
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rear end fluid

Fluid is slowly leaking from the rear diff cover. I am going to pulll it today and check it out. Is it a gasket or RTV? Any suggestions for fluids other than the recommended 75w-140 synthetic?

As always thanks for the info!
 
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Old Apr 25, 2004 | 09:19 AM
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It should be rtv, just make you sure your surfaces are very clean, as for as fluid i repalced mine with synthetic, but a regular gear will do, you'll just have to change it more often.
 
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Old Apr 25, 2004 | 10:41 AM
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I just got 4.56 gears put in and the shop was grumping about the cost of the synthetic gear oil. Because it calls for synthetic and synthetic only. I guess that cost was left out and I bet the next gear install price will go up because of the synthetic only.
RIS
 
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Old Apr 25, 2004 | 10:50 AM
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Thanks for the info. Do you use the orange RTV?
 
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Old Apr 25, 2004 | 10:54 AM
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i used black on mine.
 
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Old Apr 25, 2004 | 11:19 AM
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Use gasket maker, not RTV, to seal the diff cover.
 
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Old Apr 25, 2004 | 11:58 AM
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If you have a limited slip rear diff, you will have to add a friction modifier to the new oil at refill. The Ford recommended products in the owner's manual are specifically for the rear end and may have it added, aftermarket brands may not.
 

Last edited by Twin Tritons; Apr 25, 2004 at 12:02 PM.
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Old Apr 25, 2004 | 04:15 PM
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Thanks, I knew about the friction modifier. I just stopped by Autozone and Checker to get some gear oil and the Mobil 1 was between $12-$15 a quart!!!

I'll be stopping by Wally World later to see how much it is there.

They had Coastal synthetic also for a better price. Coastal has always scared me though. Gas station brand. Yikes.
 
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Old Apr 25, 2004 | 11:02 PM
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Originally Posted by Twin Tritons
If you have a limited slip rear diff, you will have to add a friction modifier to the new oil at refill. The Ford recommended products in the owner's manual are specifically for the rear end and may have it added, aftermarket brands may not.
I have also heard in the past to add an extra tube of friction modifier. Is this true? It seemed to help when I had my 98 Chevy.
 
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Old Apr 26, 2004 | 01:02 PM
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Rear end fluid

You might try Royle Purple Synthetic fluid. Same weight as the factory and you don't need to add friction modifier for the limited slip. I picked up some for about $9.00 a bottle.
 
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