D i s t r i b u t o r D a t a S h e e t 4L60-E, 4L65-E, 4L70-E
PART NUMBERS 77898E-K, -4K, 7K COMPLAINT Cause Insufficient line rise, 3-4 clutch failure
· Poor shift quality
Late Pump SECONDARY COMPLAINTS A worn boost sleeve can allow torque signal and reverse oil cross leakage or leakage to sump. COrrection
Sonnax valve and sleeve kits restore hydraulic integrity and prevent leakage. Kits are available in both stock replacement and increased boost ratio sizes. Early Pump Boost Valve Boost Sleeve 77898E-7K NEW O-Rings
2 I.D. grooves 1 I.D. groove Reverse Boost Valve & Sleeve Kits
77898E-K
Oversized .490" EPC spool diameter for early pumps Boost Valve The 4L60-E, 4L65-E and 4L70-E transmissions will not function properly if the wrong early vs. late design assembly is installed. 77898E-4K
NEW OEM Ratio .470" EPC spool diameter for early pumps Boost Sleeve 77898E-K Boost Sleeve 77898E-4K PRODUCT 77898E-7K Oversized .490" EPC spool diameter for late pumps Each includes the following 1 Boost Valve 1 Boost Sleeve 2 O-Rings
Note: U.S. Patent No. 6,619,323 Sonnax Part Summary Vehicles with a 4L60-E, 4L65-E or 4L70-E transmission frequently have poor line rise, which can result in 3-4 clutch, 2-4 band failure or poor shift quality. The duty cycle of the EPC solenoid causes the boost sleeve to wear quickly. Oil entering the torque signal orifice leaks past the boost valve and exhausts at the reverse orifice, resulting in poor line rise. Reverse oil can exhaust both to the sump and back through the torque signal orifice. The outside diameter of the boost sleeve also allows some leakage through the pump body, which decreases pressure rise. Sonnax has developed three o-ringed version reverse boost valve and sleeve kits, 77898E-4K for OEM ratio (.470" EPC spool diameter) early pumps; 77898E-K for oversized ratio (.490" EPC spool diameter) early pumps; and 77898E-7K for oversized ratio (.490" EPC spool diameter) late pumps.
PUMP DESIGN 1.907" LONG SLEEVE
EARLY DESIGN EARLY DESIGN EARLY DESIGN LATE DESIGN LATE DESIGN LATE DESIGN OEM VALVE
1 BAND 2 BANDS SLEEVE
NO END GROOVE .421" EPC 1 END GROOVE .470" EPC SONNAX WITH O-RINGS VALVE SLEEVE SONNAX "FACTORY" STYLE VALVE SLEEVE 1 GROOVE 1 GROOVE NUB END .470" EPC 77898E-4K 1 GROOVE 1 GROOVE NUB END .470" EPC 77898E-6K NO GROOVE .490" EPC 77898E-3K INCREASED RATIO VERSION OEM REPLACEMENT .470" 3 BANDS 4 BANDS NO END GROOVE .421" EPC 1 END GROOVE .470" EPC INCREASED RATIO VERSION OEM REPLACEMENT .470" NO GROOVE NO GROOVE .490" EPC 77898E-K NO GROOVE 1.810" SHORT SLEEVE 2 GROOVES 2 GROOVES ON PR END .490" EPC 77898E-7K ©2007 Sonnax Industries, Inc. 77898E-4K Rev:-, 77898E-4K 04-13-07 800-843-2600 · 802-463-9722 · F: 802-463-4059 · www.sonnax.com · info@sonnax.com 1