Fits: 2020 thru 2025 Chevy Silverado/GMC Sierra 2500HD/3500HD L5P Duramax Diesel

With the SunCoast 10L1000 Pro Loc Valve Body, several key issues are addressed in regard to the 10L1000 transmissions. This is not an approach that is simply bumping in more line pressure in hopes of ascertaining more clamping force; it’s a multi-faceted approach addressing several key issues when exposing these units to more demanding driving environments. These range from heavy towing and hauling to street racing and drag racing. 

The factory 10L1000 transmission lock-up circuit is an impressive one, in that it can make converter lockup seem somewhat uneventful. The refinement in its engagement is definitely next-level to what has been seen in the past. As nice as this feels in reference to the NVH (Noise, Vibration, & Harshness), when situations are introduced where the load demands are testing the limits or outside what the vehicle was initially designed for, it can become a huge problem. 

In the SunCoast 10L1000 Valve Body, they are specifically looking to decrease the time from initial lock-up apply to zero turbine slip. Doing this, changes the lockup circuit by replacing the torque converter clutch (TCC) valve in order to increase lockup holding apply fluid pressure. The lockup oil transition time is also improved by modifying critical oiling circuits for the fluid to reach the TCC clutch, resulting in quicker apply time, and therefore, reducing TCC clutch degradation. By reducing degradation per apply cycle, it allows for improved reliability and performance.

The next facet addressed is the lube circuit. The lube circuit on the 10L1000 transmission is responsible for supplying oil to the planets, clutches, bushings, etc. From the factory, the lube circuit oil is dispersed throughout the transmission as low as 6 PSI. Under normal load demands, this is perfectly acceptable. In more stressful and demanding situations, an increase in lubrication to clutches, steels, planets is ideal for removing heat and dealing with the increased demands. 

This 10L1000 Valve Body specifically addresses this circuit from 6 PSI to a whopping 20 PSI. This is a 250% improvement from the factory calibration, resulting in reduced frictional heat generated. The reduction in heat helps lessen premature failure that can become increasingly evident in high-horsepower applications.

Another modification to the valve body involves the regulator valve (latch valve) circuit. This oil circuit is responsible for fully engaging the clutches, allowing for full clutch line pressure. In factory form, the regulator valve being specifically targeted is responsible for A, B, C, and F clutch packs. Of course, the primary clutch pack concern is the 'F" clutch, which tends to be the first and most prominent clutch pack failure with the 10L1000 in higher horsepower or more demanding environments.

In a factory 10L1000 valve body calibration, the regulator valve (latch valve) becomes fully engaged, allowing full fluid flow for engagement at 120 psi. When this occurs, the oncoming clutch pack has maximal clamping force. When the clamping force is engaged to max capacity, the greatest static and dynamic holding capacity is created. In stock form or even mildly modified vehicles, this is perfectly suitable; however, when the vehicle is exposed to more demanding environments, this can be a weak link.
This valve body decreases the required pressure to fully engage the regulator to only 80psi. This is a 33% decrease in pressure needed to maximally engage the clutch regulator valve (latch valve) resulting in a quicker shift apply when engaging clutches A, B, C and F. This quicker engagement not only shortens shift times, but it also decreases the heat resonating in the clutch pack, preventing premature degradation and extending clutch life. To improve this shift calibration even more, non-critical oil is evacuated to increase apply rate.

The factory overall line pressure is modified on this new SunCoast pump/valve body combo, increasing overall main line pressure by as much as 60psi. This additional line pressure not only increases the maximal clamping force of the individual clutch packs, but also increases overall pump volume production. To reduce the potential for runaway pressure and the over-compression of clutch fibers, the SunCoast 10L1000 Valve Body has a built-in bypass, dumping excessive pressure above 420psi.

Features:

• Increased Line Pressure, as much as 60psi
  
• Increased clamping force on all clutch packs
  
• 250% Increase in Cooler Charge Pressure
  
• Increased Lock-up Apply Pressure
  
• 33% Decrease in Maximal Pressure Actuation of Clutch Packs
  
• Shortened Shift Times
  
• Improved Clutch Wear

Notes: 

• For maximum results in power levels exceeding 800HP, it is highly recommended that the TCC apply offset be changed in the factory file calibration
• All Core Return Costs are responsible to the customer. Please contact our customer support team with any core return questions you may have. Core returns must be processed online via the Return Request Form