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Used 4T40 Transmission

1995 was the year GM launched its 4T40 transmission. This 4-speed model was one of the new automatic builds that were picked to replace the outdated turbo-hydramatic family. While the 4T40 has since been replaced by the 6T40, it is still a build that is in demand for a number of GM manufactured or subsidiary brand vehicles. Buying a used 4T40 transmission is super easy using this automotive website.

The RPO code that is used to identify a 4-speed 4T40 is MN4. This is the authentic GM naming scheme that mechanics, auto builders and resellers use when ordering inventory. One thing that General Motors did differently with its transverse platform was it updated its weight system. Vehicles that are rated at 4000 pounds or less were able to use the 4T40 without fear of burning out the gear or clutches.

Replacement 4-Speed GM Transverse Transmissions

The very first public installation of the 4T40 happened with the Cavalier. The 1995 edition was the initial showing the auto buying public. At the same period in time, GM cross promoted the Corsica and Sunfire vehicles with the 4-speed models. Since the gearing was setup for automatic compatibility, there are slight changes in the way that vehicles are geared depending on the 4T40.

The base ratio for the electronic geared units are 2.95, 1.62, 1.00, 0.68 and 2.14 for the reverse gear. The torque can be rated differently. There are changes to the sprocket design that might affect what type of unit is found in used condition at a retailer website. For someone who will buy a 4T40 used, becoming aware of minor but essential information is a huge help.

What to Know About the 4T40 Transmission

GM designed two different units at the same time. The first was the 4T40 and the next was the 4T45. There are small differences in the gear ratio. Each model is a 4-speed and is compatible with the newer Ecotec motors. The second edition model RPO code is MN5. Before purchasing a preowned condition assembly, making certain that a dealer offers a complete unit is the key.

A complete 4T40 transmission in used or rebuilt condition should always include the electronically controlled torque converter. Some dealers remove this assembly and charge extra to have it put back on. When the internal gearing cannot be verified, a gearbox might not be as reliable as expected. PreownedTransmissions.com provides units that are always evaluated and intensely overhauled to guarantee the condition.

Prices for Used 4T40 Automatic Transmissions

There is a price tool on this page that reveals all unit sticker prices. For someone new to the second hand auto parts industry, all distributors offer a different range in price. Some companies are higher and some companies are lower. Each unit found retailed here is packaged professionally for delivery. It comes with its own term of warranty coverage along with free freight to a USA address.