The General Motors 4L80E transmission was designed for longitudinal engine configurations in October 1963. This transmission is a modified version of the Turbo-Hydramatic TH400, so it isn’t unusual that it has most of the internal components of the TH 400.
The 4L80E transmission, despite having similar components and a reputation for being extremely strong, adds lockup torque converters, overdrive gears, and sophisticated electronic controls.
We’ve gone over the 4L80E gearbox in-depth, including its features and what makes it popular today, since it has been 10 years since its creation was discontinued.
What is 4L80E Transmission?
The definition of the 4L80E four-wheel-drive system is a four-speed (4), longitudinally-mounted (L), 8000 pounds vehicle weights for (80), and electronically controlled transmission. The ‘E’ means it requires an Electronic Control Unit to operate and provide firmness.
The 4L80E performance transmission was created to fit cars with engines up to 440 ft. lbs. (597 N·m) of torque, weighing up to 16,500 pounds GVWR. Commercial vehicles, passenger vehicles, and trucks are among the vehicles that have utilized the 4L80E transmission.
This transmission was also used in Bentley and Rolls-Royce. This gearbox, for example, maybe found in GM vehicles such as the Silverado, Suburban, Sierra, and Hummer H1.
The 4L80E is a heavy-duty automatic gearbox that was created from the TH400, a huge-duty automated gearbox with no lockup torque converter or overdrive. As a result, there was a requirement for a big-duty automatic transmission with overdrive to be developed.
GM’s decision to move the solid-state 4L60 from a direct-drive system used in its full-size trucks to an independent gearbox with tailshaft for smaller models was driven by commercial concerns. As a result, it needed a new transmission that incorporated many internal components and designs from the TH400 to compete in this market.
4L80E 4×4 TRANSMISSION TECHNOLOGY
The Powertrain Control Module (PCM) controls the 4L80E gearbox. The driver has the choice of selecting shift maps based on the action they wish to perform, such as towing.
The PCM has a section of its shift stabilization plan that aids to minimize hunting. A PWM lockup solenoid, on the other hand, governs the 4L80E torque converter (in factory mode) and helps to guarantee a smooth lockup.
The 4L80E has two-speed sensors that are used as a turbine input speed and output speed. The input speed sensor is utilized to keep track of input speeds, which are compared with the engine speed and output shaft sensor speed.
The collected data is applied to alter the shift speeds in response to the current conditions. It’s also worth noting that there are several locations for the speed signal, and it is determined by when the gearbox was released.
4L80E 4x4Transmission Strengths
The COMPUSHIFT ETC is a variant of the popular 4L80E gearbox, which uses an electronically controlled system. It may be linked to a 4L80E transmission controller such as the COMPUSHIFT for improved shift timing and TCC lockup. The transmission controller’s sensors provide information on the transmission’s condition.
For a smooth operation, the torque converter clutch may be switched using pulse width modulation (PWM). The TCC links the engine output shaft to the transmission without loss in rotation speed.
The third gear is probably the most important to your engine’s longevity. It provides extra overdrive gear ratios for additional stability, improved fuel efficiency, reduced noise levels, and less engine wear while driving on the highway. It improves GM’s 4L60E transmission by allowing it to handle more horsepower and torque. As a result, the 4L60E is designed to accommodate vehicles weighing up to 6000 pounds, whereas the 4L80E is intended for ones weighing up to 8000 pounds.
4L80E 4x4Transmission Weakness
The transmission cooling line connections were behind the bell housing on early versions of the 4L80E from 1991 to 1996. This method didn’t always provide enough lubrication to the rear planetary, and it was inadequately cooled, causing problems as it became too hot and was damaged while in use.
The fifth-generation gearbox began to be used in Europe on the Citroen C4 of 2002, with automatic versions available from 2003. From this time on, new versions of the transmission design were introduced, including modifications to improve cooling and lubrication of the oil feed cooler mounted at the rear of the case.
Lack of Lubrication
When the forward drums do not have enough oil for lubrication and cooling, the clutches may slip and cut grooves in the drum. When the drum attempts to apply the clutch package, it will only partially apply it rather than properly engaging teeth.
Torque Converter Clutch failures
The engine tends to spin faster at regular speeds and, as a result, consumes more fuel than it needs to with the condition that the torque converter clutch fails to get locked. The clutch piston of some 4L80E transmissions produced before 2006 has been known to fracture.
If the Torque Converter Clutch (TCC) fails and stays locked, this might cause the engine to stall when you come to a stop since the torque converter will fail to disconnect power from the engine to the wheels.
Difference Between 4L80E and 4L60E?
The General Motors Company produces both the 4L60E and 4L80E automobile transmissions. The 4L60E is a conventional transmission utilized in rear-wheel automobiles launched after 1993, while the 4L80E is generally only available in diesel and large block vehicles. The two have distinct origins, performances, looks, and pricing, with the 4L80E being considerably more powerful than the 4L60E.
The 4L80E is considerably more powerful than the 4L60E. Because the power of an engine would typically destroy a lesser, less powerful transmission, 4L80E transmissions are required in vehicles with strong engines, such as large trucks for towing or high-speed vehicles for racing. The 4L60E is powerful enough to work with most stock vehicles.
The 4L80E has an oval-shaped pan, whereas the 4L60E has a rectangular pan. Similarly, the greater size and longer durability of the 4L80E, necessitates more bolts to connect to the engine, which is reflected in its larger size and greater robustness.
The 4L80E costs far more than the 4L60E due to its larger dimensions, greater power, and intended use on engines with higher horsepower. The 4L80E is also better value for big trucks and high-speed vehicles with big engines since the 4L60E is vulnerable to shattering when used on a powerful engine.