The 3T40 used to be called a TH125 transmission by General Motors. Most people are aware this edition was built for the first time in the year 1980. What some people might not know is that the 3-speed models were one of the very first automatic assemblies produced for GM automobiles. There are some slight differences between models although most units offer the same technologies. A Chevy 4T40 transmission is for sale on this website as a second hand edition.
There are variations in part numbers although most of the 3T40 units are very similar to the 125C editions. When a “C” is included in the part number, it means that GM has installed a torque converter clutch system. This removed the dependency on the hydraulic systems used in the early 1980s. Starting from 1982 forward, all TCC enabled modules were variably controlled.
GM 3T40 Naming System
Before the 4T40E beat out the 3-speed editions, GM changed its numbering system to make it easier to order parts. Buick, Pontiac and Chevrolet all used variations of classic part numbers. This is why there is virtually no difference between a 125 3-speed transmission and the renumbered 3T40 editions. The 3500 engines from Pontiac and other popular 4-cylinder blocks were coupled with the smaller gearboxes until the year 2002.
When someone goes to replace an older GM gearbox, it is common to lookup the gear ratio. Since there are used editions that have been modified, it never hurts to know the OEM specs. The 3T40 transmission gear ratio is 2.84, 1.6, 1.0 and 2.06 for the reverse gear. This produces what is known as a 3.18 final drive ratio. Some retailers just publish the final ratio instead of including all of the individual gear sets.
GM 3T40 Transmission Warranties
It is very likely that all pre-2002 produced units are out of an original warranty term. Many of the early policies were produced up to a 30,000-mile mark. Even after the MD9 was replaced, it was possible to get an extension of coverage from a car dealership. CPL works with retailers nationally to acquire components that still have a valid warranty provided. These are aftermarket coverage plans and guarantee a period of protection for buyers.
Prices for 3-Speed Gearboxes Online
The national price locator system built into this website takes the hard work out of shopping for used car parts. In order to compare the price for a used GM 3T40 transmission for sale, a person only has to provide CPL with the model year. It is optional to input a VIN number or actual RPO code. These can be matched at the checkout should a person go through with an order.