J_ho67

So my friend just bought a 2000 Z28. He got an awesome deal actually. A real steal. Anyway he and I were taking a cruise down the highway and I noticed he was only running about 1500 RPMS at around 65MPH. I figured because they have the 6th gear while we only have the 5th.
So my question is, would it be wise to put a 6-speed in a GT? I know the Cobra has one, but have never heard of anyone putting it in a GT. Would it work? And what gear set up should I use. I drive agressively when I want, but would really like to keep alot a drivability in it just because it is my daily driver. If it is to be done, should I use the Cobra transmission? Any info in this, any advice or examples of other people that have tried it would be awesome. Thanks in advance.

Tim37

its a t56 if you google you can find quiet a few companies that make a kit to swap one right in to a gt its no big deal. it runns about 2500 for every thing. i usualy try to cruise at 2k so you would have to be doing about 80 to put it in 6th unless you put some gears in it.

ShadowDrake

I don't really see any problem with swapping a TR3650 from a mid 01-04 GT with the T-56 from the Cobras. Someone will need to confirm if it will bolt right up to where the old transmission was though. I think it will. It is a good swap, but not worth the cash unless your current transmission is failing and needs replacement anyway. Keep the factory gears that are in them (maybe change first and second to be not so steep) and put 4.10s in the rear. Fifth gear ratio on the TR3650 is .68:1 if I am not mistaken, sixth gear in some T-56's is .5:1.

Just looked up the ratios:
TR3650
http://www.ttcautomotive.com/English...ts/TR-3650.asp

T-56
http://www.ttcautomotive.com/English/products/T-56.asp

I can't tell you which exactly are in the Mustangs, you would have to contact TTC about that. That should give you an idea of the ratios though. In my GT with factory rear gearing, at 70 MPH in fifth, I'm at 1800-1900 RPM. I get into the flowmaster drone zone at 80+ MPH which is just over 2k RPM.

n/a_threat

I'm actually thinking about doing it, and yes it can be done. I just don't like the 1st gear ratio on the 3650. I emailed ttc yesterday to see if I could put a 2.97 or 2.66 to replace first gear from the two models of t56. If I can, I'll do that rather than swapping for a t56.

This is the place that gave me the idea:

http://www.ddperformance.com/

There are a few components you have to consider before doing anything, i.e. how much hp/torque you have now and want to have. What size wheel/tire combo and rear end ratio. It does take some planning.

Just something to consider though, the T56's 5t & 6th gears are both o.d. gears. So, unless you like cruising at 75+, you probably won't use them too often in town. And if you are just making a little bit more than stock hp/torque, stick with the 3650 and get some 4.10s.

JD1969

My SS is a 6 speed and I don't recall the last time I used 6th gear. I really only use it on long trips on the interstate and thats it. That might change after I swap in a 4.30 gear but I doubt it.

nathansmith50

i'm putting one in my gt next summer.

here is a good link for a complete kit.
t56 kit

i'm getting it because i have 3.90s and it revvs a little high when i'm on the highway because i like to cruise at about 80-90.

and because the t45 sucks **** and in my eyes isn't worth fixing( my throwout bearing is going)

black01gt

I wouldn't go 6 speed unless u had a blower with some big horsepower.

David_K

chevy was really smart in putting a 6 spd in the z28 and a 5 spd in the six cuz now you can have a z28 that gets the same gas mileage as the v6 on the highway

RacinJason2316

I have the Viper T-56 in my car with a Pro-5.0 shifter. I love the tall 1st gear and double OD 6th for supercruising at around 120 with my 3.73 ring and pinion. What I don't like is the way the trans shifts. I have had 4 different shifters on it and they all felt notchy and stiff. I have about 10,000 miles on the trans and it hasn't loosed up even a little. I am either going to get a TKO-600 or convert to an 4R70W with a 10" lockup converter. Lentech makes a bitchin street/strip 4 speed auto that will grin at whatever you throw at it. THe T-56 is strong, but it's not worth the cash. The G-Force T-5 is much cheaper and shifts a whole bunch nicer.