GM Manual Transmissions – Use Gear Vendors to Save Gas or Diesel Fuel, Extend Chevrolet or GMC Mileage. Use Muncie SM465, SM420, M21 and/or Borg Warner T10 to Extend Engine Life. Start Saving Money Today!
Does your Chevrolet or GMC need more power to climb hills or tow with heavy loads? Would you like to be able to at a touch of a button, have taller gearing for cruising down the highway with the lower engine RPM's and improved fuel mileage? See our GM 2-Wheel Drive Manual Transmission application guide . These Chevrolet GMC overdrives are available for 4 speed manual transmissions in 1958 and newer muscle cars and street rods, 1988-1992 3/4 and 1 ton pickups as well as Chevrolet, Buick, Oldsmobile and Pontiac cars. Our Chevrolet GMC overdrive transmission provides 500 to 600 less RPM's plus 20% increase in fuel economy. You'll need an auxiliary overdrive transmission capable of gear splitting behind your Muncie SM465, SM420, M21 and or Borg Warner T10. The toughest built best performing GM auxiliary overdrive transmission you can buy is the Gear Vendors overdrive from Drivetrain Specialist. Call us at 800-216-1632 to order yours Today!
See How It Works - Guaranteed Amazing Performance for Your Chevrolet or GMC!
How it works: gears are multipliers of torque and our ratio splitting capability allows you to shift to a gear with more mechanical advantage than the next stock gear in automatic transmissions and wide ratio manuals. This also means engine rpm drops about half what it did without the Gear Vendors and so rpm is sustained - higher torque and rpm on shift = more Horsepower. When shifted into overdrive final gear reducing both rpm and torque to reduce the HP when steady cruising to improve fuel mileage and decreases wear on your engine. Two-year warranty rated at 30,000 pounds applications for Chevrolet and GMC, most good when used in commuters, tow vehicles, 5th wheels and Motor homes. Our overdrive kits are very complete and are designed for your specific vehicle. Detailed installation instructions are included in kit, and installation is also available. Building a muscle car or street rod? See this YOUTUBE video of a Camaro utilizing our Gear Vendors overdrive unit.
Related to fuel economy, performance, and emissions — Gear Vendorss overdrive units include state of the art electronics circuits that keep your vehicle in the optimum performing gear. Whether you are driving an older non-computer controlled vehicle or a late model with all the latest emissions computers our electronics provide the interface to ensure maximum performance and correct rpm without lugging or over revving in the wrong gear. The OE factory programming remains intact and our processor just makes it aware of the actual ratio 1,000 of times per second. In older vacuum or throttle linkage transmissions the stock governor on the output shaft instantly slows down the moment the overdrive shifts and so automatically moves the shift point in any overdrive gear up by the correct 28.6%. So both electronic and non-electronic automatic transmissions gain a group of features including a passing gear or climbing gear that is automatically available without driver intervention and is at the split between 2nd and 3rd where you really want it. Need more information on how to save gas or diesel fuel?
Call our Overdrive Expert Today and get Free Shipping at 800-216-1632!
You get all the benefits of the Gear Splitting performance and overdrive economy (see your appropriate transmission below and the best auxiliary transmission you can buy. Give our overdrive expert a call toll free 800-216-1632. He can answer your questions and help you pick the correct model for you application. Get free telephone support during installation when you buy from www.drivetrain.com. Free shipping within the continental United States only.
You need quality
You'll want reliability
You want performance...22% overdrive
You want better mileage...20% more fuel!
YOU WANT A Gear Vendors
YOU GET ALL THESE BENEFITS & MORE
Bolt on Performance!
Save Fuel 20%
Extend Engine Life
Save Money
30,000 lbs Capability
2 year factory warranty
You want more power to climb hills or tow with heavy loads
At the touch of a button taller gearing for cruising down the highway with the lower engine RPM's and improved fuel mileage. You'll need an auxiliary overdrive transmission capable of gear splitting. The toughest built best performing auxiliary transmission you can buy is the overdrive from Drivetrain Specialist. 22% overdrive 20% fuel savings, two year warranty rated at 36,000 pounds applications for GM 4 speed manual transmission, most beneficial when used in tow vehicles, 5th wheels and Motor homes. Ideal for both diesel and gas pickup trucks and other vehicles with early Muncie SM465, SM420, M21 and or Borg Warner T10 transmissions. Our overdrive kits are very complete and are designed for your specific vehicle. Detailed installation instructions are included in kit. Installation is also available if you prefer. Choose your vehicle from the following table to see detailed information on improving your vehicles performance and start saving money today!
The Muncie 465 is the widest ratio 4-speed of the Big Three. It has a granny low and so then just 3 normally usable ratios. See the final drive ratios chart and notice the extreme benefit there is to gear splitting by using the Gear Vendors.
You will have an Eaton 2-speed switch on your shift lever to control the Gear Vendors (turning it on/off) while depressing your clutch. The.78 to 1 overdrive ratio will increase you vehicle speed by 28% or reduce engine RPM at a given speed by 22%.
Fuel savings are typically over 20% in both diesel and gas applications. This overdrive unit will pay for itself while giving you tremendous performance gains in torque multiplication and horsepower.
Manual 4-Speed Muncie M-21 - 32 Spline, One Piece Adapter.
Replaces tailhousing.
50 to 57 Cars cars and street rod trucks.
$2,945.00
Muncie M20/21/22
3DFSM21C
Manual 4-Speed Muncie M20/21/22 - 27 Spline.
Replaces tailhousing.
60's and 70's muscle cars and street rods.
$2,745.00
Muncie M20/21/22
3DFSM21E
Manual 4-Speed Muncie M20/21/22 - 32 Spline.
Replaces tailhousing.
60's and 70's muscle cars and street rods.
$2,745.00
Muncie M20/21/22
3DFSM21G
Manual 4-Speed Muncie M20/21/22 - 27 Spline.
Replaces tailhousing using 2-piece adapter.
58 and newer muscle cars and street rods.
$2,745.00
Muncie M20/21/22
3DFSM21I
Manual 4-Speed Muncie M20/21/22 - 32 Spline.
Replaces tailhousing using a 2-piece adapter.
58 and newer muscle cars and street rods.
$2,745.00
SM420
3D0420C
Manual 4-Speed Muncie M-420.
Replaces Tailhousing.
50's-60's Truck, Manual, Custom kit AA.
$3,145.00
SM465
3D0465C
Manual 4-Speed Muncie M-465.
Replaces Tailhousing.
60's-92 Truck Manual w/mechanical speedo.
$2,845.00
SM465
3D0466C
Manual 4-Speed Muncie M-465.
Replaces Tailhousing.
88-92 3/4 & 1 Ton pickups w/cast iron 4spd & electric speedo.
$2,845.00
T10
3D0T10C
Manual 4-Speed T-10 12 1/8" Long Tailhousing 27 Spline.
Replaces tailhousing.
Chevrolet, Buick, Oldsmobile, Pontiac cars.
$2,745.00
T10
3D0T10E
Manual 4-Speed T-10 12 1/8" Long Tailhousing 32 Spline.
Replaces tailhousing.
Chevrolet, Pontiac, Oldsmobile, Buick cars.
$2,745.00
T10
3D0T10K
Manual 4-Speed T-10 11 7/16" Long Tailhousing 27 Spline.
Replaces tailhousing.
Chevrolet, Pontiac, Buick, Oldmobile cars.
$2,745.00
T10
3D0T10M
Manual 4-Speed T-10 11 7/16" Long Tailhousing 32 Spline.
Replaces tailhousing.
Chevrolet, Pontiac, Oldsmobile, Buick cars.
$2,745.00
Check out the unlimited horsepower warranty and money back guarantee and the simple installation in the dimensions section. Then order give us a call. Need informatiion on other overdrive applications choose from below:
We have included a frequently ask questions section that may answer some of your questions, don't see answers you need, just give us a call we will be happy to review your application with you. The following links provide specific application information, performance data that you can expect and the price data for your specific vehicle.
Free technical support is available call 775-276-4090, talk to a Drivetrain expert get answers to repair or upgrade questions, also help in automotive diagnostic problems.
Like to ask a question before you place your order, its easy just email us.
Overdrives 
electronics circuits that keep your vehicle in the optimum performing gear. Whether you are driving an older non-computer controlled vehicle or a late model with all the latest emissions computers our electronics provide the interface to ensure maximum performance and correct rpm without lugging or over revving in the wrong gear. The OE factory programming remains intact and our processor just makes it aware of the actual ratio 1,000 of times per second. In older vacuum or throttle linkage transmissions the stock governor on the output shaft instantly slows down the moment the overdrive shifts and so automatically moves the shift point in any overdrive gear up by the correct 28.6%. So both electronic and non-electronic automatic transmissions gain a group of features including a passing gear or climbing gear that is automatically available without driver intervention and is at the split between 2nd and 3rd where you really want it. Need more 
