Ring gears, stub shafts & differentials

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Dattebayo
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Joined: Sun Aug 25, 2002 10:04 am
Car: 2004 Nissan Frontier Desert Runner
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I was hijacking a thread earlier about this.

So the question goes:Can you use a differnt ratio ring gear from any r200V and make it fit and work correctly into another with out swapping the stub shafts?Are there any problems with this idea?Are there any other parts involved for the swap?

That is all...


pmkls2
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Joined: Wed Jul 16, 2003 6:19 am
Car: 1990 240SX Fastback

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well, as far as I know the ring gear ratio has no effect on what stub shafts you use, however, there are more parts involved in the swap (pinion gear, shims, etc...) and you need to know how to set up a differential unless you want it to last a couple thousand miles before you eat the gears or bearings out of it. besides there arent many different ratios available for these rearends that I know of and most all of the factory ones are the same except for the 300ztt

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Hijacker
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Car: '92 240sx Convertible
'94 F-150
Location: Fredericksburg, VA

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swapping ring gears is a PITA and expensive on our cars. I landed a relatively new VLSD out of a low mileage silvia last summer, but it came out of the carrier and minus stubs and ring gear. I had the joy of rebuilding the rear end. It's fairly involving, and the shims you need are $16 a piece at the dealer.

A picture says a thousand words:



If you look, you can see that the diff sits sideways. The pinion gear drives the ring gear, making the diff rotate on an axis. That axis happens to be the stub shafts that go into the sides of the diff carrier. When the coupler engages, it locks both wheels together to the best of its ability and causes them to turn at the same rotation.

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Dattebayo
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tenkawa_akito wrote:A picture says a thousand words:
Or a thousand parts...

Yeah i sorta knew all that stuff but iguess i didnt really figure it all out correctly.

So waht i hear is that i really shouldnt mess with it even though i have a severe mechanical inclination and have a little money on the side...

(P.S. I thought you could use washers instead of shims for the stubs...)

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Hijacker
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Joined: Wed Aug 13, 2003 4:57 am
Car: '92 240sx Convertible
'94 F-150
Location: Fredericksburg, VA

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the shims are machined to specific tollerances. We're talking thousandths of an inch difference between them. Washers aren't machined to such exact tollerances and I would NOT reccommend thinking about using them.

The problem with rear end build ups is not whether or not you have mechanical inclination. Tooth reading is something that I feel should be taught by someone who has rebuilt quite a few rear ends. Had I not had a man who has rebuilt more rear ends than I can count watching me, I don't think I could have done mine on my own, and I consider myself to be a fairly good mechanic.


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