This is our abused transmission, removed from an LS1-powered F-body. |
GMHTP follows along as Joe Huneycutt of T56Rebuilds.com turns a clapped-out T56 into a better-than-new gearbox. |
Joe uses a custom workbench with a hole in it, so that the input shaft can slip through the table surface. In this photo, the tailshaft housing was removed. |
Within the wide world of performance car enthusiasts, there exists an unwritten fraternity of brothers and sisters. This group takes pride in being in full control of a thoroughbred vehicle's mechanical aspects. We hot rodders have another nickname for this group; we call them "gear-bangers." A certain amount of street and track credibility is earned when a driver pilots his own car sans slushbox.
Sooner or later, these hard shifts and high-rpm clutch dumps take their toll on the internals of a transmission--and this is where Joe and Amber Huneycutt from T56Rebuilds.com step in. We got an opportunity to visit their shop located in Houston, Texas, and snapped some photos of the entire disassembly and rebuilding of a T56 six-speed transmission. Joe has earned a reputation as a talented builder, and is a graduate from the School of Automotive Machinists. Joe takes pride in practicing what he preaches, as you can find him grabbing gears across the country in his orange LS1-powered Camaro. His car is no slouch either, as he bangs out four gears in about 10 seconds flat down the quarter-mile.
Rebuilding a T56 is not a chore that most people would eagerly dive into. It takes a few special tools, and plenty of practice and patience. The pile of moving parts can be very confusing and intimidating to look at, but T56Rebuilds.com is here to help show us the ropes. If you find that you can't put Humpty Dumpty back together again, give Joe and Amber a call so they can get you back on the track.
The bottom of the transmission has a set of donut magnets, which are there to catch metallic debris. We found our culprit in the form of a busted key block stuck to the magnet. That doesn't belong there! | 
Joe uses a custom made gear puller to remove the Fifth and Sixth gear assemblies from the mainshaft. If you need one of these, Joe will build you one. | 
On the Fifth gear assembly, we find the common signs of wear. The shift fork on the upper right has worn black pads on the ends. On the gears the points at the tip of each gear are rounded off. |
After Fifth and Sixth are removed, the main housing can be removed to expose the rest of the gear sets. | 
Joe discovers the remains of the keys that were stuck to the magnet; they were sheared off of the Fourth gear assembly. | 
A gear puller is installed between Second and Third gear, and a hydraulic press is used to remove them from the shaft. |
When everything is disassembled, this is the pile of parts you end up with. Now we get to have fun replacing the worn components and putting things back together. | 
Joe shows us a comparison between a Mikronited (left) vs. factory (right) countershaft. Mikroniting is an optional process that reduces friction between moving components, resulting in lower operating temperatures. | 
Here is a set of Mikronited (left) First through Third gears, compared to factory spec gears. First gear is the larger diameter pair at the rear of the photo, with Second being in the middle, and Third closest to the camera. |
This photo compares the upgraded steel 3-4 shift fork (left) to the weaker factory aluminum fork on the right. These aluminum forks are known to bend after a series of hard slamming shifts. | 
A comparison of the upgraded carbon fiber 3-4 blocker ring (left) shown next to the paper lined factory ring on the right. Paper inside your transmission, that can't be good! | 
This is a new 3-4 synchronizer assembly. It is one of the most common items to get replaced during a rebuild. Quit missing Third gear! |