Open rear diff???????
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Senior User
Joined: Oct 2015
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Open rear diff???????
Whiskey Tango Foxtrot.. over!
Does this truck really have an open rear diff.
So I back into a yard, pretty firm, to ****** a tree stump. Right rear tire spins, and packed full of mud, the other three high and clean. Someone please tell me I just have a worn out clutch pack in a limited slip?
Does this truck really have an open rear diff.
So I back into a yard, pretty firm, to ****** a tree stump. Right rear tire spins, and packed full of mud, the other three high and clean. Someone please tell me I just have a worn out clutch pack in a limited slip?
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I've got axle code 39. Should be 3.55's. I had a LS in 8.8 in my 2003 Mustang. It would give up a little. Then I changed the 3.23 to 3.73 and re-shimmed and and installed new clutch disks. It would lay 2 very nice black lines down, with I think the drivers side fading barely before the passenger. I know LS diff clutches and springs can wear, but this thing acts like straight open diff. I searched this and a couple other forums, and guys where talking about welding the diff, and buying LS diffs, which led me to believe that open diff's did exist in these trucks.
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Joined: Mar 2006
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From: western SD
Axle code 39 would be an open diff 3.55, as per this page Ford Axle Code Chart - Ford-Trucks.com a limited slip 3.55 is a C3 coded axle.
My bad, it should be a code C9 for a 3.55 limited slip. Don't know why I hit C3.
My bad, it should be a code C9 for a 3.55 limited slip. Don't know why I hit C3.
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Axle code 39 would be an open diff 3.55, as per this page Ford Axle Code Chart - Ford-Trucks.com a limited slip 3.55 is a C3 coded axle.
BOOOO!! So I suppose my best option is to find a junk yard C3? I imagine an aftermarket limited slip is $400 + then you have to set it up and all.
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Lead Driver
Joined: Mar 2006
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From: western SD
The only thing bad about a junk yard rear, is you won't know the conditions of the clutches. If you have to rebuild the thing, you would probably have about as much into it as getting an aftermarket locker. See my edit above, you need a C9 coded rear.
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From: knoxville, tn
I have had good with the junk yard one I found. There is a way to check the clutch pack. IIRC if the rear end is off the ground and you turn one wheel then the other one should turn in the same direction. When I pulled mine the fluid was nice and clean and there was no junk in the bottom of the chunk which made me feel pretty good about it. And worst case was that it acted like the open rear I already had. So I was good with the risk
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Senior User
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I have had good with the junk yard one I found. There is a way to check the clutch pack. IIRC if the rear end is off the ground and you turn one wheel then the other one should turn in the same direction. When I pulled mine the fluid was nice and clean and there was no junk in the bottom of the chunk which made me feel pretty good about it. And worst case was that it acted like the open rear I already had. So I was good with the risk
