GM Banner

GM Transmissions

Interested in the 2004R overdrive transmission? It’s definitely one of the transmissions that hasn’t gotten a lot of attention, but don’t be discouraged by what this trans can do in terms of performance. It’s nearly as strong as a 700R4 and can bolt into most Chevy’s without needing much modification. The 2004R was introduced in 1980 to be used in the Chevy Corvette and Buick Grand National until it was phased out in 1990. Today, many vehicles still use the 2004R to give older cars an overdrive gear and more horsepower.

Features of the 2004R Transmission

If you are considering putting a 2004R transmission into your older vehicle, here are a few things to know.

  • Improved Performance. Because the 2004R is an overdrive transmission, you can significantly improve performance in your vehicle. Take your car to the next level by upgrading your current TH350 or TH400 to the 2004R.
  • Reduced Fuel Consumption. Overdrive transmissions make better use of fuel because the car’s engine speed decreases when using overdrive gearing. In addition to having improved fuel efficiency, there is less wear and tear on the vehicle.
  • Easy Installation. Another benefit to the 2004R is that it has easy installation and is surprisingly affordable. They can handle around 250-400 horsepower and is the same length as Powerglide and TH350 transmissions.

2004R: Easy Install and Great Price

2004Rs are getting harder to find, but they remain a great replacement for an older two-speed Powerglide or a three-speed Turbo Hydra-Matic. The reason for this is because you don’t have to make major adjustments. Plus, the fourth gear lets the engine rotate at a lower RPM, reducing fuel consumption and wear and tear on the drivetrain. You can also change the larger rear axle ratios without affecting streetability.

Gearstar builds high performance transmissions, and we highly recommend the 2004R because of its straightforward installation and reasonable price tag. Because this transmission is an analog model, it doesn’t rely on a computer to tell it what to do like its “E” siblings. This is part of the reason why the price tag is smaller than other transmissions. Give Gearstar a call and have one of our expert technicians build you an analog transmission with reliable overdrive. You won’t regret it!