TKO 500 or T56 6 speed tranny? Help me decide

the man is set.

I just got D&D's t56 about 600miles ago. things pissa, i love first gear, it is so useful! but if you are going to go this route, i would highly suggest going higher than 3.73's outback. I have those gears now and i wish i went with a more agressive gear with this trany. i didnt plan on getting it this soon so the 3.73's would have suited my driving pleasures just fine. but when the t5 went it was time for something serious, a life long part. don walsh sr told me that this trany is capable to hold 1000+hp and like 900lbs of torque. it cost me with the installation kit around $3300 for all parts and like $350 for install. if you can get the money get this trany and it will be your last one.
Fawcett
1995 Gts
13.3@103.6 before the t-5 went on street tires
340bhp frpp 302, afm super king cobra clutch, afm alum flywheel, t-56, alum d/s, 3.73's. track heat intake, 24lbs, 65mm frpp tb, pro m 80 and cai, march underdrive pulleys, brembos all around, cobra r's, mac unequal length shorties, o/r h pipe, chokemaster delta 40's mallory digital ignition, aeromotive fpr, holley 190lph, plus more....

I run a TKO 500 and I was in the same boat, trying to decide between the T-56, TKO 500, and TKO 600. I called Tremec and asked a few questions.

About the TKO series: The difference between the 500 and 600 is that the 600 has the higher first gear (high 2.xx something, forgot) while the 500 has the lower first gear (3.27) which is a little higher than stock (3.35). The 500 you can get with either the stock style 10 spline or the 26 spline, while with the 600 you can only get the 26 spline. The 500 is just as strong as the 600 with the 26 spine but even with the 10 spline it's good to 575TQ. I have the 10 spline because I just got a clutch and couldn't afford a new one. So with the 10 spline 500 the weakest point is the input shaft, and if I break anything I hope it is the input shaft, alot better than the whole tranny. I had to modify the H pipe and the crossmember, but otherwise it was bolt on install.

The T56 is a great tranny, no doubt. I have some F body friends and I can say I really like the T56. The first gear is higher like a TKO 600 but the rest of the gears are evenly spaced apart, so when you shift your rpm's will drop equally between all gears. One thing that really sets it apart from a 5 speed is that when you top out 4th gear you can go to 5th and the rpm's don't drop near as much, but when you want to cruise, the high 6th gear makes 4.10's cruise like 3.55's. So even though the T56's first gear is higher, you can put in some steep gears to make up for it, have real close shifts, and keep the rpm's down on a road trip. On a drag race application, there isn't any real advantage, it would really help a road race application where speeds vary alot, and would be nice for a street car.

astronut1885 said:

I think with a blower and my motor, I won't need the higher gear. I'm shooting for atleast 350 RWHP, but I may end up with more. Highway driving is an inescapable evil for the next three years atleast. I think with that power and 3.73s I'll be alright. I know I need a smaller driveshaft, I'll probably just get the whole install kit from D&D. On the tranny crossmember mount points, how do those get relocated? Do you cut the whole bracket from the car, slide it back, and then reweld it? If so, I can probably handle that with my mechanic. The clutch won't even come off the block, because it's the same imput as the T56. The bellhousing might be a pain, but once it's in, it seems like a bolt in and weld in affair. Did the T56 come with instructions for install and all that? Thanks for the info!

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Mine didn't come with instructions but basically if the regular T56 is the same as my Viper, which i assume it is, it's completely different than a T5. The T56 has a slot for the clutch fork that is half in the bellhoushing, half in the tranny. So basically you put the bell housing on the motor then lift the tranny up into the bell with the clutch fork and throw out bearing installed on the input shaft. there is no dicking around with the clutch fork. It's real slick because you don't have to mess with insalling the tranny and bell as one unit and it's much easier to get to all the bolts.

As far as the crossmember, the install kit will have a new one along with U brackets that go over the unibody frame rails. once you have the tranny installed on the bell and motor, bolt the cross member to the tranny and lift it up and mark were the brackets will need to go in relation to the frame.. Personally I welded them on, one it's stronger, and two drilling the holes would have been a complete pain. Just remember if you have subframe connectors installed.. You will need to notch them out so the U brackets sits on the factory frame rail, otherwilse it will lower to whole tranny and will probably cause clearance issues with the exhaust, plus the shifter will sit too low as well. Install over all is pretty straight forward.

man, in all honesty dont waste your money on something you wont need. the t56 is more of a luxury tranny than anything. there are plenty of 5 speed trannys out there that can handle the power you are planning on putting out, plus some. ive got a tko 500 and it feels so solid that im positive that i will break something in my motor or rear end before i break anything in the tranny (the shifts are smooth and solid, with no slop and absolutely no missed shifts or over shifting). the tranny almost shifts itself. its hard to explain, but the "slots" (if you want to call them that) where the shifter goes when its in gear, feel so much tighter and closer together than the t5. honestly its a great tranny and im so glad that mike (sirsureshot) talked me into getting it