Performabuilt has it covered as well as everything else possible.
“Our Extreme 4X4 Max Series is ideal for rock and mud crawling. This series is very similar to our Heavy Hauler, except it’s built with climbing and spinning in mind. It has slightly more aggressive shifts and more punch built in. It is ready to head to the mountains or play in the bog – your choice.
We use a heavy duty wide band for maximum hold in 2nd and 4th gear. To compliment this, we use the Corvette servo. This servo is the largest servo available from GM. It will supply the clamping force needed for these heavy units but without the excessively harsh shifts associated with the aftermarket “super servos.”
For the 3-4 clutch, we use 8 heavy duty friction and steel plates. More friction plates than stock; which is 6 in most cars and trucks. Some additional modifications to the 3-4 set and this clutch pack prevent scoring and burning and increase hold. This build also includes the Sonnax input drum reinforcement kit with the billet support collar and the billet piston.
We next attack a weak link, the sun shell. In particularly heavy vehicles, vehicles used for heavy loads, and those used for off-roading, constant shifting occurs from first to second and reverse. To address this, we use only THE BEAST. These sun shells do not break. They are almost twice as thick as a hardened or new OEM shell and they have a reinforced collar. You will not have to worry about that sudden loss of reverse, 2nd, and 4th gears associated with the breakage of this piece.
To further address the issue of heavy loads and extreme stress, we have added the GM 5-pinion planetary gears and a special proprietary modification that supports both the Low Roller and the Intermediate sprags with clutches. By having the clutches engaged when the Low Roller or Intermediate Sprag are activated, we eliminate the common issue of a “rolled sprag”.
For the Extreme 4X4 transmissions we only use the thicker “K” cases that came in the very high performance cars and 4×4 trucks. You won’t have to worry about cracked bell housings and cases.
