How do I find out my rear end gear ratio?
#1
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I know there is a way to do it by turning the wheels and counting the rotations of the driveshaft or something like that....but I live in the city and have absolutely no garage or tools to work with....Is there any way to tell by the VIN or anything like that? its a 99 TA A4. thx
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Look in the drivers side door jam, there will be a list of codes on a sticker, look for the GUx code, if its a GU2 code you have a 2.73, I don't recall the other code but if it GU5 its a 3.23 ratio
Last edited by Brett H; 01-05-2005 at 05:40 AM.
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get on the freeway if your a4 put it in 3rd if your m6 put it in 4th and do 75 mph your tach will read you gear ratioor close to it........................3230 = 323 3700=373 ect
#4
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GU2 Axle Ratio 2.73, Rear
GU4 Axle Ratio 3.08, Rear
GU5 Axle Ratio 3.23, Rear
GU6 Axle Ratio 3.42, Rear
G80 Axle Positraction, Limited Slip
GU4 Axle Ratio 3.08, Rear
GU5 Axle Ratio 3.23, Rear
GU6 Axle Ratio 3.42, Rear
G80 Axle Positraction, Limited Slip
M6 GU6 3.42 Standard
A4 GU2 2.73 Standard
A4 GU5 3.23 Optional (standard gear set with an SS/WS6/Firehawk)
A4 G92 3.15 (Vette optional)
A4 GU2 2.73 Standard
A4 GU5 3.23 Optional (standard gear set with an SS/WS6/Firehawk)
A4 G92 3.15 (Vette optional)
You can look on the RPO sticker (should be on the drivers door).
If you have the code:
GM8 = 2.56
GU2 = 2.73
GU4 = 3.08
GU5 = 3.23
GU6 = 3.42
If you have the code:
GM8 = 2.56
GU2 = 2.73
GU4 = 3.08
GU5 = 3.23
GU6 = 3.42
GU2 Axle, Rear 2.73 Ratio
GU3 auto tranny,
GU4 Axle, Rear 3.08 Ratio
GU5 Axle, Rear 3.23 Ratio
GU6 Axle, Rear 3.42 Ratio
GU3 auto tranny,
GU4 Axle, Rear 3.08 Ratio
GU5 Axle, Rear 3.23 Ratio
GU6 Axle, Rear 3.42 Ratio
No F bodys came with 3.73 from the factory!! Check your door, if you have GU5=3.23.
GU2=2.73 and I think 3.42 is GU6. All SS and WS6 cars came with either 3.23 (Auto) or 3.42 (Manual). If you have a Z28 or regular Formula or Trans-am, you have a 2.73, unless you orderd a performance gear upgrade from the factory.
GU2=2.73 and I think 3.42 is GU6. All SS and WS6 cars came with either 3.23 (Auto) or 3.42 (Manual). If you have a Z28 or regular Formula or Trans-am, you have a 2.73, unless you orderd a performance gear upgrade from the factory.
3.23 and 3.42 are 3 series carier. 2.73 is 2 series carier.
GU5 is 3.23
GU2 is 2.73
GU6 is 3.42
GU5 is 3.23
GU2 is 2.73
GU6 is 3.42
there is no single rear end ratio for ALL the 93 automatics, my buds 97 TA had 2.73s for god sakes, look in your glove box or on the driver's door for the RPO code sheet, its filled with 3 digit codes, find GU#
GU2 is 2.73 GU4 is 3.08 GU5 is 3.23 and if you're really lucky GU6 is 3.42 G80 is positraction rear end.
GU2 is 2.73 GU4 is 3.08 GU5 is 3.23 and if you're really lucky GU6 is 3.42 G80 is positraction rear end.
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#5
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Originally Posted by ACW
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https://ls1tech.com/forums/showthrea...18#post1193436
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https://ls1tech.com/forums/showthrea...18#post1193436
No F bodys came with 3.73 from the factory!! Check your door, if you have GU5=3.23.
GU2=2.73 and I think 3.42 is GU6. All SS and WS6 cars came with either 3.23 (Auto) or 3.42 (Manual). If you have a Z28 or regular Formula or Trans-am, you have a 2.73, unless you orderd a performance gear upgrade from the factory.
GU2=2.73 and I think 3.42 is GU6. All SS and WS6 cars came with either 3.23 (Auto) or 3.42 (Manual). If you have a Z28 or regular Formula or Trans-am, you have a 2.73, unless you orderd a performance gear upgrade from the factory.
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#7
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Hey jw if you could tell me how i can quickly and easily figure out what gear ratio my rear end is my rear end is out in my truck and i cant get a new one bc i have no idea what the gear ratio is and every time i call to see if someone has a rearend for my truck thats what they ask me. i drive a 1994 4x4 GMC yukon with a 6 inch lift on it. One problem i have is that this thing was originally a deisel and now has a 350 in it so i don't know what else has been modified b4 i got it
Last edited by txbabe_090503; 06-15-2011 at 06:29 PM. Reason: messed up sent it b4 i was ready