| You are looking at the PerformaBuilt Heavy Hauler Series Transmission.
These units are built very similar to our pro race units except the key is on durability while maintaining reasonable shift quality. These were specifically developed for the commercial, heavy towing and 4x4 vehicles. The shift on these units is designed to take the abuse and work associated with these vehicles but without the tire chirping shifts of our race and performance units.
These units feature a heavy duty pump with staked bushing, full-time lube modification to keep the heat down and modified lockup valve to improve the lockup converters durability so you Can tow in overdrive.
On the internals we use the following:
We use a heavy duty wide band for max hold in second and fourth 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.
Then for Fourth (OD) we use the sonnax dual piston servo. This servo has 30 percent more holding force than the stock overdrive servo. That accompanied with the 20 percent wider band will let you tow in overdrive with confidence. Now you have near double the load capabilities of the stock transmission in overdrive.
Next we use carbon composite frictions in the forward clutch. These frictions have an outstanding friction coefficient for max holding. This clutch has to bear the load in every gear except reverse and at the same time. This clutch has superior temperature capabilities so they don’t burn easily in even the worst conditions.
For the 3-4 clutch we use the ALTO heavy duty 9 friction redlined clutch set 3-4 more frictions than stock equals 30 percent more holding in this critical pack which must handle full engine load in both 3rd and 4th gears. This set has shown to be and excellent upgrade.
Now we address the weak link in the particularly heavy vehicles and vehicles used for heavy loads or 4x4 where there is constant shifting from first to second and reverse is used for more than backing out the drive way - the sun shell. To address this, we use only THE BEAST. These sun shells do not break as they are nearly twice as thick as a hardened or new oem shell and a welded reinforced collar. You will not have to worry about that sudden loss of reverse and 1st and 3rd gears only associated with the breakage of this peace.
Moving on to the planetary, both sun gears are machined with slots to increase lube flow. This is a must in these heavy duty units. A lack of lube and cooling is a killer when pulling the boat, camper or that work trailer loaded down with equipment. The heavy hauler series use 4 pinion planets.
For this unit we only use the thicker K case like is used in the very high performance cars and 4x4 trucks. You wont have to worry about cracked bell housings and cases.
Lastly we address the valve body. Here we perform all the updates for lube and durability, eliminate the partial lockup function in the 4L60E. This greatly extendes the converter life and helps to keep everything much cooler. Next we improve the flow to the 3-4 clutch making sure it has enough supply to help ensure it holds the load on this crucial shift. We then enlarge the apply release feeds for the lockup clutch to make it apply positively to avoid converter clutch burn up under heavy load. Finally we include a low stall heavy duty carbon composite lockup clutch torque converter; this heavy duty unit was made for this use without failure.
As with all our units shipping is free in the mainland usa and there is no core charge! And since we know you need your Truck 1 handing time is generally 4 days or less in most instances. Shipping is to your residence or any business address with no additional charge, This Unit comes with our PerformaBuilt warranty for 1 year, Regardless of the miles you drive or your use! If it dies you simply return it and we get another one or the one you returned right back to you within days not weeks, Warranty is limited to repair of the transmission at our facility, we are not responsible for any other loss incurred, wages,R&I cost or any other loss.
Thank you for viewing our Tough addition to the PERFORMABUILT family! |