I have a 99 gt with an upgraded t-56 transmission? What gears do i have? When a transmission is changed are the gears always swapped as well? Thanks for any help guys

 

one way you can check is to put a mark on your sidewall of your tire, and mark your driveshaft. as you complete one full rotation of the tire, count how many times the driveshaft spins. ex: if it spins 3 1/4 times you have 3.27s, if it spins 3 1/2 times you have 3.55s, 3 3/4 you have 3.73s, 4 times you have 4.10s. or you can take the differential cover off and it will be stamped on the gear.

 

You can also try this:

 

One caveat in this situation is whether the T-56 was installed with a proper speedometer drive gear--if not the speedometer could be off.

Use my "guesstimator" with speed recorded with a GPS to be sure.

 

Thanks guys i used the second option and figured out i have 3.27s

 

Just curious, did your speedometer prove accurate?

 

I havent tried it against a gps yet but i will try soon. This doesnt make sense to me though, if my gears remain stock, how does my sixth gear function, if the stock trans is a 5 spd?

 

I am not sure I understand your question? With the T-56 both 5th and 6th gears are overdrives, the ratios depend on what particular T-56 you have.

The T-56s used in the '03 and '04 Cobra have 0.79:1 and 0.62:1 5th and 6th gears, the so-called "Viper spec" transmission has 0.73:1 and 0.50:1 5th and 6th gears.

Personally unless one is a hard core road racer, or someone who just likes to shift gears, I don't understand the appeal of 6-speed transmission in something with as wide a powerband as even a bolt-on GT. I have driven '03 and '04 Cobras and if I owned one the first thing I'd do would be to put a TKO-600 TCET5008 5-speed in it--but then again I do not sell cars for a living...

 

Im not even sure if i know enough about transmissions and gears to ask correctly. Let me ask this first instead to remove some gray area for me, ok so stock gears are 3.27 with 5 speeds correct? The t-56 has six speeds, and i think i have the 03-04 termi trans. If the prior owner changed the trans to a t56, would he of had to change the gears as well? Because in my head i feel like if the stock gears were kept, the cars 6th gear would have the same ratio as the stocks reverse gear, and i also would not be able to even go into reverse because the stock doesnt have another gear (essentially "7th" gear my reverse)
I apoligize if this seems like a cluttered message, i am just a bit puzzled.

 

The transmission and the "gears" (rear end final drive gears) are separate units, one can be changed without changing the other. Your stock transmission had five forward gears and reverse, the T-56 has six forward gears and reverse.

The final drive gears have just a single ratio--3.27:1.

Here's how it all goes together: