Help with Driven Gear?
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Advanced
Joined: Oct 2007
Posts: 82
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From: Brownsville Texas
Help with Driven Gear?
I'm changing rear ends from 2.73 to 3.73 on my 86 (automatic / Dana 36). I think the correct speedometer driven gear for the 3.73 is a 45 tooth, light blue, GM Part #25513052. I could not find it at Ecklers, MA, or GM Parts Direct but I did find it at RMS Auto Parts (http://www.rmsautoparts.com/proddeta...25513052&cat=5) but it shows "out of stock". Could someone tell me if I have the right part and does anyone know where I might be able to find one? Thanks.
Last edited by adfac; Apr 1, 2011 at 05:20 PM.
Team Owner
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From: Riverside County Southern California
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http://www.ringpinion.com/PartsList....D=139&CatID=35
Before you do this speak with some owners using 3.73 gears in an automatic.
There is a big difference between 3.73 auto and 3.73 manual.
Before you do this speak with some owners using 3.73 gears in an automatic.
There is a big difference between 3.73 auto and 3.73 manual.
Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
That looks to be the correct driven gear for your swap, I know it is the one I used in my 93 when running that ratio and my speedometer was accurate. It must be matched with the 15 tooth gray drive gear.
Give this link a try.
http://www.transmissioncenter.net/sp...n_______va.htm
If you strike out finding a new one, let me know and I'll look for my old one, good luck.
Give this link a try.
http://www.transmissioncenter.net/sp...n_______va.htm
If you strike out finding a new one, let me know and I'll look for my old one, good luck.
Last edited by toptechx6; Apr 2, 2011 at 05:15 AM.
Burning Brakes
Joined: Jun 2008
Posts: 892
Likes: 1
From: New Smyrna Beach Florida
http://www.ringpinion.com/PartsList....D=139&CatID=35
Before you do this speak with some owners using 3.73 gears in an automatic.
There is a big difference between 3.73 auto and 3.73 manual.
Before you do this speak with some owners using 3.73 gears in an automatic.
There is a big difference between 3.73 auto and 3.73 manual.
I think you would be happy with 3.07 performance axle for street use. Drag strip, I could see 3.73's 
