How to ID a diff?

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Endless325
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Tue Jan 22, 2008 5:14 pm

Hi all, I'm trying to find out what ratio a diff is.

I know there's a bendy small plate on it that holds this information, but it was rusty so I tried cleaning it a little and I'm now left with a very shiny piece of metal!

Is there any other way of obtaining this information? Part numbers on the side perhaps?

Cheers
Nelly
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Tue Jan 22, 2008 6:00 pm

I'd mark the input shaft as well as one of the output shafts - then count how many turns of the out to one turn of the in :mad: dam that was confusing typing that.
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Endless325
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Tue Jan 22, 2008 8:55 pm

Cheer mate, but I'm a bit thick, can you explain a bit further?

Thanks!
Nelly
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Tue Jan 22, 2008 10:08 pm

Put a mark on the bit the prop attatches to and a mark on the casing so they match - then do the same to an out put shaft that the drive shaft attatches to - rotate the prop attatchment 360degs and count how many times the out put shaft bit turns, should be on avarage 3. 64 or 3. 91 revolotions.

Hope this helps.
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Endless325
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Tue Jan 22, 2008 10:44 pm

OK mate cheers, but how do you determine the .64 or .91?
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Endless325
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Wed Jan 23, 2008 11:55 am

If when the cars off the ground and you spin one wheel, and the other spins the opposite way, that means it's an open diff right?
Gussy
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Wed Jan 23, 2008 2:53 pm

Endless325 wrote:OK mate cheers, but how do you determine the .64 or .91?
If it's a 3.64 the input shaft will turn just over 3 and a half times to 1 full revolution of the output shafts.

If it's a 3.91 the input shaft will be closer to 4 full revolutions to 1 revolution of the output shafts.

Just mark the input / output shafts and the rotate the input shaft slowly and count the turns needed to get to one full turn of the output shaft.
Nelly
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Wed Jan 23, 2008 5:30 pm

Endless325 wrote:If when the cars off the ground and you spin one wheel, and the other spins the opposite way, that means it's an open diff right?
Correct :wink:
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Endless325
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Wed Jan 23, 2008 10:34 pm

Nice one fellas!
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