Getrag, a subsidiary of Mercedes Benz, manufactured the G56 transmissions that are in 5.9L and 6.7L Dodge turbo diesels From 2005.5 and Newer. Chrysler's factory setup of the transmission utilizes a dual mass flywheel with a single disk clutch and it is filled with ATF+4 automatic transmission fluid.

While this setup may work in its stock configuration, it often creates a problem when G56 owners upgrade their clutch. Most aftermarket clutches use a solid flywheel for performance and durability, but solid flywheels don’t absorb harmonics as well as dual mass flywheels. In high torque conditions, this creates a gear roll over which results in a growling noise coming from the transmission. This growling noise is most apparent in 4th and 5th gear at low RPMs under load.

When trying to get to the bottom of this, the folks over at CarboniteCummins found that, in fact, Mercedes Benz never intended the G56 transmission to be filled with the ATF+4 fluid. Chrysler decided on this oil not because it was the best choice, but because it was the most available at their dealerships and is 'good enough' for stock engine power setups. It saved Chrysler a lot of money, but it's not a good solution for anyone with a G56 transmission that plans on upgrading their truck. For this reason, we recommend the better-suited HOT SHOT'S SECRET BLUE DIAMOND G56 gear oil. Many people find that overfilling the transmission with a total of 7-8 quarts works best.

HOT SHOT'S SECRET BLUE DIAMOND G56 severe duy transmission fluid was formulated specifically for G56 6-Speed Manual Transmissions to help with the notorious rough shifting and excessive rollover noise they experience, especially when owners upgrade from the stock dual mass flywheel clutch.

HELPS REDUCE EXTREME HEAT Hot Shot’s Secret BLUE DIAMOND SEVERE DUTY TRANSMISSION FLUID’s improved thermal stability protects against varnish and sludge deposits to keep the transmission running clean.

IMPROVES OXIDATION STABILITY Hot Shot’s Secret BLUE DIAMOND SEVERE DUTY TRANSMISSION FLUID protects against fluid breakdown that is common with severe duty applications, such as heavy towing and challenging terrain.

REDUCES NOISE AND VIBRATION Hot Shot’s Secret BLUE DIAMOND SEVERE DUTY TRANSMISSION FLUID increases film strength and boundary layer protection with our patented FR3 Nano Technology.

PROTECTS AGAINST WEAR Hot Shot’s Secret BLUE DIAMOND SEVERE DUTY TRANSMISSION FLUID was formulated with a high level of our extreme pressure additive package for the superior protection that is needed in severe duty applications. It helps clutches, bearings and bushings last longer and perform better.