If there is one thing that stands out as a great aspect of this job, it has to be finding out about the new products the aftermarket manufacturers are getting ready to release to enthusiasts—before they are actually released. I received an email the other day from the folks at TREMEC, touting an all-new transmission that could revolutionize manual overdrive swaps.
I’m sure you know that TREMEC is a leading manufacturer of manual transmissions and components, and when the email spoke of the release of an all-new five-speed transmission, dubbed TKX, to say I was immediately interested is an understatement. This new gearbox is a rear-wheel-drive manual transmission developed solely for the aftermarket. That means you will not find this unit in a salvage yard under a late-model Camaro or a Mustang.

The team at TREMEC was able to create a relatively small unit while keeping strength a big priority. Clearance in most transmission tunnels is now available without floor modifications.
This is another great upgrade option for inclusion in your hot rod. “The sleek new design and enhanced performance make this perfect for your next restomod project,” says Mike Kidd, aftermarket business unit manager at TREMEC. “The TKX was designed, tested, and built specifically for the aftermarket.”
The fact this overdrive transmission is capable of smooth, high-RPM shifts and be able to survive behind an engine delivering 600 lb.-ft. of torque makes it perfect for both street and performance applications. But I was curious about what prompted the design of the TKX? “We listened to our customers,” says Kidd. “We then combined their suggestions with our OEM technology and strengthened our aftermarket lineup with the addition of the TKX.”
I am told that TREMEC engineers took a forward-looking approach to find the best and most efficient solution to building this new transmission. This includes universal packaging, excellent shifting performance, and extreme durability.
The end result of these design implementations is superior shift-ability with smooth shifts at high RPM through the use of multi-cone synchronizers and hybrid synchronizer rings. “The multi-cone synchronizers increase the capacity of the synchronizer by spreading the applied forces across multiple surfaces,” Mike states. “At TREMEC, we have taken that one step further with the use of a hybrid set of synchronizer rings made up of sintered bronze and carbon, thus providing a faster and smoother shift at higher engine RPM.”
While the hybrid synchronizers are of great advantage to enthusiasts, at the same time, noise, vibration, and harshness (NVH) performance are minimized with a reconfigured gear layout to best control stress levels. According to TREMEC, all gears are supported by needle bearings and utilize a reduced end play on the gears. The TKX also features a three-piece aluminum housing that consists of the main case, intermediate plate, and a rear extension.
Internally, you will also find a triple support system for the main shaft and double support on the countershaft. This along with the use of tapered bearing on all support locations create the ability for much smoother shifts than a salvage-yard swap transmission could dream of delivering. Durability is further optimized with oversized gear widths, gaskets at all flanges, and caged needle bearings in all gear positions.
I do want to let you know, this new transmission comes in at a svelte 114 pounds. While that sounds heavy, remember, a Saginaw four-speed weighs nearly the same, but without offering the advantage of an overdrive. In the Ford camp, the top-loader weighs substantially more, and again, does not give you an overdrive. Mopar guys will actually save a little weight depending on which A833 you are currently using.
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- Designed for multiple applications with little to no floor pan modifications needed
- Compact, end-loaded design provides the perfect solution for custom builds
- Outstanding shift-ability at high RPM (up to 8,000) to match modern, high-performance engines
- 600 lb.-ft. of torque capacity
- Single-overdrive reduces engine wear and fuel consumption for comfortable highway driving
One of the main selling points of the TKX is its smaller size, but how was TREMEC able to create such a small package? “We have been able to reduce the size of packaging by using the same end-loaded design used in our OEM-transmission lineup like the TR-6060 and TR-3160 found in today’s production performance vehicles,” affirms Kidd.
As you can see, the TKX offers substantial room between the case and the floor of this '70 Chevelle. That makes this a great upgrade for any enthusiast.
Now that we have discussed the technical aspects, I know the next question you want answered is, how does it fit? We asked Kidd that same question, “We actually installed the TKX in several cars,” confirms Kidd. “It was bolted into a ‘70 Chevelle, third-gen Camaro, a Fox-body Mustang, ‘69 Olds 442, and a Firebird Sprint owned by Jay Leno.” Each time, once the transmission was in place, The folks at TREMEC were more than happy with the clearance available between the transmission and the transmission tunnel area.
Every now and again, the aftermarket offers a new part that can revolutionize how upgrades are done to classic cars. The TREMEC TKX could very well be considered revolutionary. Whether restoring or upgrading a classic muscle car or a 1930s-era roadster coupe, the new TREMEC TKX five-speed manual transmission is a new performance upgrade that will deliver a more driver-friendly experience whether on the road or track.