Everybody has an opinion. Especially when it comes to transmissions. We polled a few folks in the off-highway world to see what transmissions trip their trigger. Here's what they said.
Eric Forsberg, Vice President, Novak Conversions: "The SM465 took what GM had learned about transmission design over its previous six decades and rolled it into an extremely strong, compact, and easily serviceable design. It is rare to see gearbox engineering with such polish. The 465's compatibility with essentially all GM engines (and some others) and their relative abundance make them easy to find, adapt, and use in many applications. I consider GM's 4L60-E Hydramatic to be the greatest automatic transmission in history. The 4L60-E's excellence of engineering and craft has yielded unusual strength, refinement, and elegant simplicity. Additionally, the 4L60-E's compatibility and integration with GM's Generation III powerplants are further compelling reasons to consider them in the very best factory and conversion vehicles."
Gary Heusted, professional mud racer, owner/driver of Rapid Transit and Da Judge: "In Class 3, automatic transmissions are the choice of most racers. My first choice would be a well-built Powerglide. In Classes 4-6, automatic transmissions are still the choice of some, but I believe the slipper-clutch with either an SCS, B&J, Lenco, or a reverser and a Pro Fab transfer case would be my choice and would be the toughest and most reliable."
Joey Leone, owner of Leone Off Road Racing, home of the Tropical Depression and Tropical Storm Pro Stadium trucks: "My pick for the manual transmission would have to be the Borg-Warner T-10 four-speed. It came with a yoke that carried the 1350-series U-joints and it's able to handle plenty of performance. You can also get kits that rollerize the trans, making it even better. For an automatic, I have to go with the TH350. It's an all-around great transmission and parts are plentiful and inexpensive. When built right, they can handle plenty of power. The one I use is TCI-prepped with a TCI manual valve body. I usually run First or Second gear, but on a long track, Third gear is no match for a two-speed Powerglide."
Fred Perry, experienced trail rider and owner of Clemson 4-Wheel Center: "Most of the old standby four- and five-speed transmissions are drying up or just plain worn out, but the NV3550 is becoming more and more plentiful. Parts are really available, they have a good 4.01:1 First gear ratio and a good 0.78:1 Fifth gear overdrive for the highway. They're tough enough for most V-8s too. There are many good automatic transmissions out there, but I chose to run a 545RFE from an '02 Grand Cherokee. It has a great gear-ratio spread for on- and off-pavement with a 3.00:1 First gear and a 0.67:1 Fifth gear; it's tough and fits behind most Chrysler V-8s; and it's easy to find. The electronics can be a bit of a challenge, but the end result is worth it."
John Peterson, Bigfoot Racing transmission technician: "My favorite transmission is Ford's C6. It's a very durable unit from the factory, and with a few modifications, we routinely put 1,500 hp through it."
If you're tired of getting stung by wasps while lying on the glass- and metal-covered ground of a salvage yard while trying to ogle your project transmission, take a look at TCI Automotive. The folks at TCI offer all of these automatic transmissions, plus a whole bunch more. Best of all, they've improved on them in such a way that their inherent weak points have been eliminated. Take the Ford C6, for example. The stock trans robbed horsepower due to its design, so TCI made a number of internal changes that actually cause it to use 11 less horsepower than the stock unit. All of these transmissions can be purchased with Sizzler, StreetFighter, or Super StreetFighter modifications. B&M Racing & Performance Products is also a good source for these automatics. Best of all, they're ready to bolt in your rig.
A big thanks goes out to Bryan Krystulovich at Motive Gear and Stanley Poff and Riley Jeter at TCI Automotive for their help with the technical aspects of this story.
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