"A transbrake works by locking a forward gear against Reverse at the same time through a solenoid, valve, and an electrical switch. Once Low gear is selected, a button fires a solenoid that moves a valve, which brings Reverse on at the same time you're in Low gear. Then at launch, Reverse is released by the solenoid via the valve. Usually this is a specifically designed valvebody and requires upgrades to aftermarket components inside the transmission in order for it to handle the added stress. It may also require port massaging to quickly allow fluid to get where it needs to go."
Zack Farah: "Many muscle car guys are fascinated by GM's new 6L80E trans, but its large size makes it difficult to package beneath a car and it has not had time to come of age just yet. The 700-R4/4L60E needed many years to evolve into what they can be built up to today. About 80 percent of that evolution is attributable to improvements GM made at the factory, and the other 20 percent came from the aftermarket. High-performance billet components, clutch drums, shafts, hubs, flanges, sprag clutches, and shift kits were all developed by the aftermarket. We can expect much of the same for the 6L80E. In the meantime, a 4L80 swap is a good bet for those seeking a bulletproof GM overdrive."
Stanley Poff: "We've looked at the 6L80E inside and out and it is very big, so fitment in older cars would be an issue. Also, the 6L80E hasn't responded to performance enhancements very well. In fact, the engines that they're bolted to from the factory usually incorporate a torque management feature in the ECM programming to limit the stress on the trans and prevent breakage. As an alternative, TCI has developed the 6x Six-Speed. We start with the GM 4L85E and add two gear ratios to it. This is absolutely a dream transmission for street machines. We have installed them behind many 1,000-1,200hp street cars and they hold up great. It is one of the hottest selling transmission and converter packages we have today, and sales continue to increase. Everything is dyno'd and married in our building including the TCU (Transmission Control Unit) computer to control it."
Achilles Thomas: "The pros of the 6L80E transmission are that it's a six-speed automatic, and it's extremely durable. Our website, 6l80e.com, has some basic information regarding this new transmission. Being that it's new, there are a limited amount of aftermarket parts currently available. However, that will be changing in the near future. We also have plans to release a stand-alone computer to operate this trans in older vehicles. The downside of the 6L80E is that it is a fairly large transmission, and most early-model vehicles would require running an engine adapter and computer to operate it."