mcslim

Can any any one tell me the gear ratio in my '09 LS3 with A6 paddleshift? It is turning 1650rpms @70mph with stock tire size. Do all auto trans have the same rear axles and are they different manuals? Also, does any one know the difference in individual transmition ratios spread of 6speed autos vs manuals?

Rathmullan

2.56 unless it has the Z51 performance package in which case it would be a 2.73. So no, all C6 automatics do not have the same rear axle ratio. The GS, which comes standard with the Z16 performance package and which replaced the Z51 package beginning in 2010 also has a 2.73 axle ratio when equipped with automatic.

All C6s equipped with manual transmission have 3.42 rear axle ratios.

TerryL

Are all years the same? What's the ratio in my 06 auto vert? Would the VIN tell me?

Turbo6TA

C6 Ratios

roscoe118

Thanks... I guess the dynos somehow adjust for the 1.15 gear ratio, of the A6's, in 4th???

SouthBaySurfer

As stated above, 2.56 ratio, or 2.73 if it's a Z51. However, in '08 and '09, the 2.73 ratio was free-standing option on the base car. Check your RPO sticker; code for a 2.73 rear is GU2. I have one in my '08.

pahlbfishn

I have a base c6 with the 256 and at 70mph my rpms are 1500.

Vette_DD

According to this chart, if your tranny is turning 1650 RPM at 70 MPH, your rear axle ratio is 2.73.

http://mysite.verizon.net/foofoo2/c6/A6-2.73.html

Vette_DD

Not quite. The chart above has the 2.73 gear ratio left out of it for the "Base" A6s. The chart below is more accurate.

peter pan

That is what my coupe turns and 09 was the last year you could order 2.73 with a non Z51 vette, I know we did this