Anyone want a transmission that will hold your F/I, nitrous power???
 

Well, after building a nice transmission and motor, my 3rd gear let go at WOT. I had all of the goodies in the tranny except the 9310 main shaft. Having that shaft wouldn't have saved me as it was the cluster that let go. I spoke with TJ @ RPM and I can't say enough good about them. They could have sold me another built tranny, but advised me that it wouldn't hold up to my power very well and I would be back in the same boat soon enough. TJ and Rodney said that the hot ticket would be to get a T6060. So I went on a search for just that. Using that tranny requires the matching rear end, the cradle, the spring, the lower control arms and a set of offset adapters from RKT56.
All of the 08 and up manual trans. Corvettes have this new T6060 in them. Each with different Gear ratios in them. The Z51 has the same gearing as the MN12, the Z06 has the same gearing as the M6 and the ZR1 has gearing all it's own. What you get with the T6060 is the same (or similar) as with the T-56 Magnum. The way to identify the trans is the sticker on the top. The ZR1 trans has the code GCDU on top and Z06 is GCDF. If it has UCF on it, it is 07 and older C6 Z06. I haven't seen the sticker for the Z51's yet.
I will be picking up my transmission, rear diff, cradle etc. today and posting pics as well as a write-up so that those interested in making the conversion should know what it takes.

Here's some details about the T-56, what causes the transmissions to fail and what is better about the new T6060, copied from a magazine article that I read.

How It Works
We should begin with the basics just to get everyone up to speed. Virtually every modern manual transmission consists of three shafts inside its case: the input shaft, the mainshaft, and the countershaft. The input shaft extends through the front of the case and engages the clutch hub splines, transmitting power from the engine into the transmission. The mainshaft fits into a hub in the back of the input shaft and extends out through the tailhousing of the transmission; it holds the driven or speed gears. The countershaft is located beneath the input and mainshaft assemblies; it holds the cluster gear.

The gear on the end of the input shaft meshes with an opposing gear on the cluster gear. These two gears usually are the same size and tooth count and turn at a 1:1 ratio. Because the cluster gear is usually all one forging, the whole thing turns as a unit. So when the engine is running and the clutch is engaged (foot off the pedal), these two gears turn at engine speed.

The cluster gear meshes with the driven speed gears on the mainshaft. Their differing sizes and tooth counts form the different ratios of the transmission. These driven gears are not mechanically connected to the mainshaft, however. They spin on bearings that allow them to freewheel. To understand this, consider what's happening when the engine is running with the transmission in Neutral. With the clutch disengaged, the engine is turning the input shaft and cluster gear. The cluster gear is turning all the driven gears, but the mainshaft--which is ultimately connected to the driveshaft--does not turn.

So how does engine power get to the mainshaft? The answer is through the synchronizer assemblies. Between each pair of gears is a synchronizer hub that is splined to the mainshaft and turns whenever the wheels turn. The synchronizer hub looks like a toothed wheel. It is encircled by a sliding sleeve or collar. This slider has internal teeth that match the external teeth on the hub. The slider's teeth also match the beveled dog teeth machined into the face of each driven gear. When you move the shift lever, the shifter forks move the slider forward or backward, causing it to engage the dogs on the gear face and the teeth of the synchronizer hub. When this happens, that gear is locked to the mainshaft, causing it to turn.

For the slider to engage the dogs on the driven gear, the two must be turning at almost the same speed. Consider a simple two-speed transmission with a 2:1 low gear and a 1:1 high gear. At an engine speed of 6,000 rpm, the input shaft and cluster gear are also turning at 6,000 rpm--so is our freewheeling high gear on the mainshaft. However, the mainshaft, synchronizer hub, slider, and driveshaft are turning at half that speed--3,000 rpm--because of the reduction of our 2:1 low gear. Attempting the shift would be very difficult. There are too many parts traveling at different speeds, making it nearly impossible to execute a smooth, grind-free shift.


How It Breaks
Now that we've gone over how it works, we can address how it breaks and how to make it better. As you can imagine, the blocker rings, sliders, and dog teeth take the harshest beating, especially under the sloppy shifting of a ham-fisted owner. But the parts that break are usually gear teeth and shafts. When a gear is selected, the dogs of that gear are encircled completely by the sliding collar, and power from the engine is spread out over a wide area--not so much with the gear teeth, however. The cluster gear and driven gears mesh in a relatively small area of contact--that's why the gear teeth will often break before the dogs are sheared off. There are a few options to solve this breakage problem: Use harder steel to make the gears, make the gears bigger or wider, or reduce the pitch of the gear teeth. Some of these options are more expensive than the others, but the best option for all-out performance is to do all three. That's where we move into the high-performance transmission market.

OE Plus
OE transmissions are a series of compromises made to allow quiet operation, smooth shifting, and long life. Unfortunately, these characteristics can make for clunky operation at the racetrack or worse yet, a box of ugly metal chunks when you put a lot of power to it. Tremec has just released a stronger version of the ubiquitous T56. Dubbed the T56 Magnum, it is filled with a number of improvements gleaned from years of R&D, racing in the American Le Mans series, and working with the OEs designing transmissions to go behind newer and more powerful engines in the Corvette Z06 and ZR1, Cadillac CTS-V, and Dodge Viper.

We discussed these improvements with the guys from Tremec. Product engineer Kevin Ryan told us one of the first improvements made was to increase the size of the input shaft and upgrade all the bearings in the box. The input shaft bearing is now nearly twice as large as the original T56, and all the bearings are made of better materials. Next, they switched to a proprietary blend of 4615 steel, a high nickel and molybdenum alloy that is stronger than stock but still easier to machine than the ultrahard 9310 steel used in most all-out racing boxes. The 4615 steel is used throughout the box--all the gearsets and shafts are made from it.

The gears in the T56 Magnum are wider than those in the T56. "That was a challenge," Ryan says. "We had to put bigger gears inside a case that was the same size as the original design." To accomplish this, Tremec changed the way its driven gears are manufactured. Most gears are forgings that include the dogs and the tapered cone that is engaged by the synchronizer blocker rings. All of these things need to be wide enough for the cutting tools to fit around those various surfaces to machine them properly. In the Magnum, two-piece gears are used. The gears and dogs are separate forgings that are laser-welded together. They fit tighter because they do not have to design in extra space for machining tool clearance. This tighter fit means a wider gear can occupy the same space.
For faster, more precise shifts, the linkages were altered for shorter throws, and triple-cone synchronizers were used on First and Second gears, replacing the old T56's double-cone design, while the remaining forward and Reverse gears got double-cone synchros. The synchros are all larger in diameter, too.

These changes significantly increased the amount of power the new T56 Magnum can support. It's rated at a validated 600 lb-ft, and remember, this is a stringent testing regimen that the OEs require to make sure the parts will last throughout at least the life of the powertrain warranty. In reality, the Magnum could likely handle quite a bit more power depending on a number of factors, such as the car's weight and what type of clutch and tires are being used.

So what are going to get?? Thanks for the info, I will be going down this road soon myself.:cheers:

Good stuff! Thanks

My RPM has taken a licking and kept on ticking. When should I look to upgrade?

When it quits ticking or when you want something stronger. With a working trans, it's worth some $$. A broken one,,, not so much.
Just depends on whether you want to and can afford to be proactive or reactive I guess.

I have a T6060 for the Z06. It's waiting on me. I am leaving early to pick it up. :willy:

:iagree: This is the only way too look at it. Man very nice write up.:cheers::cheers: MAN POST PIC,S OF THE BUILD ARE PUTTING IT BACK TOGETHER..:thumbs:

Great write up, keep us posted!

We have a level V six speed from RPM and havent been able to hurt it yet.... The differential is what scares me, not the trans its the toughest one they make.

Fantastic explanaitons - thank you for taking the time to share :cheers:

What ball-park price is there for this new setup - inlcuding the magnum /T6060 trans? :lurk:

Is the T6060 same/different - vs. magnum?

I may need one before too long - but it sounds like I have to get the whole "kit" -including diff & cradle??:)

The T6060 is a tough motherfu*#er! This thread will be awesome:cheers:!

If you make enough power, it's only a matter of when, not if. RPM will tell you that most of the upgrades are to improve shifting. The billet keys are also to prevent catastrophe from them breaking. Micropolishing reduces heat, but doesn't really make it stronger. The 9310 mainshaft helps, but the cluster is what you have to worry about.

If you're doing the labor yourself, plan on spending about 5k

Thanks Matt! :thumbs:

I appreciate it Scotty! :flag:

I just got it to the house.
Here's some pics.
Notice the differential and transmission each has a cooler.


http://www.bradbury.org/bret/t6060_line.jpg

http://www.bradbury.org/bret/t6060-line2.jpg

http://www.bradbury.org/bret/diff_block.jpg

Here's the pump, integrated into the T6060
http://www.bradbury.org/bret/transpump.jpg

http://www.bradbury.org/bret/Z06Diff2.jpg

Good Info, however how and exactly did you break your tranny, especially in 3rd gear /

I'm doing same as you but with the auto trans and C6 Z06 rear combo.

I thought you didn't have to change the lower control arm to the C6's if you run coil overs ?

You're right. You don't need the control arms if you have coil overs. I don't and I'm broke now.

broke it doing 2nd gear roll racing. 3rd gear runs off the cluster, which is a weak link compared to 4th, which runs by locking up the main shaft without interfacing the cluster gears. Check your PM's in a few minutes and you'll see. :thumbs:

Thanks for the PM. I here ya about the $$$'s. At least you're being pro-active and not re-active and doing the upgrade.

Too bad my car is still in the shop, as I was going to sell the coil overs I have cheap, as I want to change over to the different ones.

:cheers: Tony

:lurk:

Hey Bret, great write up dude, I have now a few more of these set-ups if anyone is interested please give me a call.

We are also a Distributor for RPM & Monster Clutches in the US, so give me a call for some of the best pricing and customer service anywhere.

Thanks guys,:cheers::cool::flag:
Mike Yeager
Eastcoast Performance & Corvette
1-864-404-1776

Sorry Matt. You have a PM too. :D

:bigears:lurk: