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Building a Four-Speed Dodge Automatic For Ultimate Performance

Dodge Ram Triple Threat Transmission

Jason Sands
May 1, 2011
Photographers: Jason Sands
Transmissions have perhaps the toughest job in a diesel vehicle. In the case of the ’94 to ’02 Dodge 47RH and 47RE units, they have to withstand almost 2,000 lb-ft of diesel torque in some applications. We knew our ’95 Dodge project vehicle, nicknamed Project Triple Threat, would see drag racing and sled pulling as well as street driving, so we set out to build the ultimate triple threat transmissionone that wouldn’t be too harsh for daily driving yet could withstand the rigors of a performance application. For this task, we worked with Brown’s Diesel in Riverdale, California. With a pair of 1,200hp common-rail Dodges to its credit, we were sure Brown’s could help our Ram put the power to the ground. Follow along as we take our stock Dodge 47RH (found in ’95 and ’96 models) and build it to withstand more than 700 hp at the wheels.
Photo 2/17   |   1105dp Dodge Ram Triple Threat Transmission transmission Apart
A Transmission For Any Budget
So just because we built a $6,000 transmission, does that mean everybody needs one? Nope, depending on your application, you can get away with a lot less. If you’re the type of person who swears you’re going to leave your vehicle at a stock power level, Brown’s can build a unit with a single-disc torque converter, Goerend valvebody, and stock replacement shafts and clutches for $3,000. Adding a triple-disc converter and billet-steel input shaft (recommended for up to 500 hp) bumps the price up to $4,500, and going with all three billet-steel shafts (input, intermediate, and output) and upgrading the clutches bumps the price up to around $6,000. Depending on the end user’s driving style, a full-billet transmission will handle anywhere from 700 to 1,200 hp. If you’re planning on doing boosted launches and torque-converter-locked shifts, the reality is even a full-billet transmission can break, but setting it up this way gives one the best possible chance of survival.
Keeping a Budget
’95 Dodge Ram 2500 $5,500
96 hp free modifications FREE
Brown’s/Goerend 47RH (including rebuild labor) $5,836.16
ATS billet-steel flexplate $525
Governor springs (Garmon’s diesel) $250
Labor cost to perform free mods $100
Labor for install of transmission $480
Governor spring installation $150
Total parts $6,611.16
Total labor $730
Project total to date $12,841.16
Performance with free modifications: 17.52 seconds at 73.5 mph, 230 rwhp and 625 rwtq
Performance with upgraded transmission: 16.94 seconds at 76.5 mph, 230 rwhp and 625 rwtq


Brown's Diesel
Riverdale, CA 93656
Goerend Transmission Inc.
St. Lucas, IA 52166
Garmon's Diesel Performance
Griffin, GA 30223