Rear diff lube.
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Junior User
Joined: Dec 2005
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Rear diff lube.
I have a 8.8 with Ford posi rear end. I was wondering what kind of fluid to put in it. I put in Lucas 85w-140w. I was wondering if this is ok. Also I'm going to drain and add fluid to the front diff. Im guessing it is a dana 44. What fluid should I use for the Dana?
Elder User
Joined: Jun 2005
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From: northeast, KY
no, positive traction (or posi) means that both wheels get equal amounts of power all the time (like putting in a spool, or welding up spider gears). Their not practical for everyday driving because when you go around a corner, the tires squeal and put a strain on the axles.
The limited slip means there's clutches that kick in when one wheel spins a certain amount of times. This is better for a DD because you can go around corners and he wheels will turn at different speeds. That's why you have to add friction modifier to a limited slip, because the clutches need the modifier to grab each other, if not, they'd probably just burn up while rubing together and trying to give traction to the wheel that isn't spinning.
I don't know what kind of category a locker is, because its an open diff until you it locks, and also it uses gears to "lock" the two wheels together and making it a posi.
Their two different things, for sure.
Matt
The limited slip means there's clutches that kick in when one wheel spins a certain amount of times. This is better for a DD because you can go around corners and he wheels will turn at different speeds. That's why you have to add friction modifier to a limited slip, because the clutches need the modifier to grab each other, if not, they'd probably just burn up while rubing together and trying to give traction to the wheel that isn't spinning.
I don't know what kind of category a locker is, because its an open diff until you it locks, and also it uses gears to "lock" the two wheels together and making it a posi.
Their two different things, for sure.
Matt
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Senior User
Joined: Feb 2005
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Ah' Mtthwvn73's Posi- Traction is a GM terminology and does have clutch's like a a Ford Limited Slip.
Same thing with a different name under different manufactures.
Same thing with a different name under different manufactures.
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Elder User
Joined: Jun 2005
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From: northeast, KY
Your 100% correct. I had to look it up, but your definatly right. So what would you call one with a locker, I found out welding up the spider gears is called a Lincoln locker (I guess for the Lincoln welder). Also FWIW, Eaton made the lockers for Chevy, didn't know that, just thought I'd throw that in.
Sorry for the mis-information, I'm definatly Chevy ignorant, lol.
Sorry for the mis-information, I'm definatly Chevy ignorant, lol.
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Joined: Oct 2006
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From: Davis & Newcastle, CA
You said it was posi, which technically is correct because its the same idea as limited slip. Either way, you need to either use a "limited-slip" gear oil or add a friction modifier. I know that Redline makes limited slip additive in a bottle about the size of a pill bottle, it doesn't take much.
After you change the gear oil, if there is clicking and chattering coming from the rear end then you need to add some friction modifer in increments until it goes away. Do not use too much or you clutches will slip all the time and render the limited-slip properties useless. If you have not used some kind of additive for the limited slip and you are not hearing clicking/chattering then your clutches for the LS are probably bad. The sure fire way to tell is to jack up the rear end and spin one of the tires by hand. If the opposite tires spins in the same direction then the LS works, if it spins in the opposite direction then your clutches are fried. Hope that helps!
After you change the gear oil, if there is clicking and chattering coming from the rear end then you need to add some friction modifer in increments until it goes away. Do not use too much or you clutches will slip all the time and render the limited-slip properties useless. If you have not used some kind of additive for the limited slip and you are not hearing clicking/chattering then your clutches for the LS are probably bad. The sure fire way to tell is to jack up the rear end and spin one of the tires by hand. If the opposite tires spins in the same direction then the LS works, if it spins in the opposite direction then your clutches are fried. Hope that helps!
Elder User
Joined: May 2007
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From: Solon, Ohio
Originally Posted by mrl390
I thought the opposite wheel was supposed to spin the opposite direction if you have LS. You cant spin the wheel fast enough by hand to engage the clutches.