ZF 6HP26 Transmission Shift Solenoid Kit, 7-Piece

Seven-piece shift solenoid set for the ZF 6HP six-speed automatic. It replaces the pressure regulator, torque converter clutch and shift solenoids that sit on the 6HP valve body, and covers the 6HP19, 6HP21, 6HP26, 6HP28, 6HP32 and 6HP34 variants. Cross-references ZF part numbers 1068298045 and 1068298046.

Vehicle coverage runs across the rear-drive platforms ZF supplied from 2002 to 2011: BMW 323i, 325i, 328i, 335i, 335d, 335is, X3, X5, 535i GT and the xDrive variants; Audi A4, A6 and Q7; Jaguar XJ8; Hyundai Genesis and Genesis Coupe; Kia Borrego; Aston Martin DB9; Maserati Quattroporte. Check your ZF part number or the fitment chart before ordering - the 6HP family uses more than one solenoid layout across model years.

Solenoids are what fail first on these units, usually before the mechatronic sleeve or the clutch packs. The symptoms are consistent: a harsh or banging 1-2 shift, a long flare between gears, torque converter clutch shudder at light throttle around 40 to 50 mph, delayed engagement into drive or reverse when cold, or a hard drop into limp mode with P0729 through P0736, P0741, P0776 or P0778 stored. Windings drift out of spec as they heat-cycle, the regulator loses its pressure curve, and no amount of fluid service brings it back.

On the bench the job is a pan-down repair - the transmission stays in the car. Drain the fluid, drop the pan (the pan and filter are one assembly on most 6HP applications, so plan on a new one), unclip the solenoid retainers and pull the harness connectors. Solenoids come straight out of their bores. Seat the new ones fully, re-clip the retainers, and refill through the fill plug to the correct fluid temperature - the 6HP has no dipstick and the level is set hot, by overflow. Clear the adaptations with a scan tool afterward so the TCU relearns shift pressures instead of holding the compensation it built up for the worn set.