SunCoast Category 2 4R100 Transmission (No Converter)

• Are designed with a softer, more resilient base paper.
• Assure less wear against opposing steel plates.
• Reduce the incidence of steel plates burning and warping.

The Intermediate Sprag

The factory sprag in the 4R100 transmission unit is notorious for failing when exposed to high levels of fatigue. This could include vehicles exposed to heavy towing or hauling or just higher-than-normal torsional fatigue. These factory sprags are typically 24- or 34-element sprags. In all SunCoast builds, these are replaced with heavy duty 45 element sprags. This is an increase of up to 53% over the factory, offering unmatched performance and ensuring that premature failure does not occur.

Transgo Valve Body Calibration Kit

The valve body is the central nervous system of your transmission. Everything that transpires within the unit begins here. In our SunCoast builds, we exclusively use the TransGo HD2 Tugger Kit. This valve body calibration kit is perfect for exhaust braking and doubles the low clutch holding pressure in manual first gear for reliable downhill braking. You also have the ability to adjust shift firmness to your desired preferences. With the improved converter feed capacity, you benefit with better cooling and lubrication.

Corrects/Prevents/Reduces:

• Codes 628, P1740, P1744
• Soft shifts
• 2nd and 3rd burn-up
• Converter burn-up
• Reverse delay
• No reverse hot
• Converter slide/shudder
• Pump buzz

Also Includes:

• Pressure regulator boost valve
• 1-2 shift valve spring
• Line regulator valve
• Innovative line-to-lube components
• High temp direct clutch seal
• Coast clutch HD snap ring
• OD housing spiral lock snap ring
• Updated direct clutch outer seal
• Calibration plate for firmness adjustments
• Quick-fill valve
• L/R mod boost valve

New Solenoid Pack

The 4R100 is equipped with a solenoid pack that controls shifting from gear to gear. This solenoid pack is comprised of electromagnetic solenoids. The integrity of these solenoids is imperative, as the flow rate and spray pattern could affect shift quality and clutch life. When failure occurs within the unit, it is not uncommon that the same particles and sediments you find in the bottom of the pan are also in the solenoids. This contamination of the solenoids can and will affect the fluid delivery to critical circuits within the unit. 

In this SunCoast 4R100 transmission, we replace the solenoid pack with a new one to ensure consistent shifts and long clutch life. 

New Bushing Kit

As with any standard rebuild, this 4R100 transmission also includes a new bushing kit, which also includes a new front pump bushing.

The Input Shaft

The input shaft on the 4R platform has always been the first weak link to bear it's head once additional horsepower is applied. In this Category transmission the factory shaft is replaced with our 300 maraging billet input shaft.