6HP26 Master Rebuild Kit 2003-2010

If you are tearing down a ZF 6HP26 from a 2003-2010 BMW X5 or X6, a 5, 6 or 7 Series, a Jaguar XJ, XK or S-Type, or a Land Rover LR3 or Range Rover, this is the rubber and paper side of the job. Although it is titled as a master rebuild kit, what ships is the gasket and seal set shown in the photo: the gaskets, lip seals, O-rings and sealing rings the transmission needs to be put back together tight. It does not contain friction plates or steels. That makes it the right box when your clutches measure good and the complaint is leaks, hot-side pressure loss or a reseal during a mechatronic or pump repair.

What this kit does in a 6HP26

The 6HP26 is a first-generation ZF six-speed, and every shift depends on oil pressure reaching a rotating clutch drum or brake piston without bleeding off on the way. That oil passes through sealing rings on the turbine and output shafts, piston seals in each drum, and O-rings at the pump, case passages and mechatronic bores. After a decade of heat cycles that rubber hardens and shrinks. Pressure leaks between circuits, the control unit compensates with longer fill times, and shifts go soft and late when the fluid is hot. Replacing every seal at once restores the sealing the mechatronic was calibrated around.

Symptoms this kit addresses

• ATF leaking at the pan, bell housing seam, output shaft or the mechatronic connector
• Soft or slow upshifts and a delayed Drive or Reverse engagement once fully warm, with clean fluid
• Oil wicking into the BMW mechatronic connector, followed by communication faults and the transmission emergency program
• On Jaguar and Land Rover units, gear ratio codes P0729-P0735 and P0783 have also been tied to worn bushings, so inspect them while it is apart

How to confirm before you buy

Drop the pan first. Clean fluid and magnets without friction paste mean the clutch packs are serviceable and a reseal is a fair repair. Heavy debris or burnt fluid means the frictions are done; in that case buy the 6HP26 kit with frictions included instead. Our BMW 5 Series 6HP guide and Jaguar 6HP guide walk through the common faults, and the ZF 6HP rebuild cost guide helps you decide between a reseal and a full overhaul.

Fitment

The listing covers the 6HP26 in BMW 5 Series (2003-10), 6 Series (2003-08), 7 Series (2002-09), X5 (2003-10) and X6 (2007-10), Hyundai Equus (2009-11), Jaguar S-Type (2002-07), XJ (2002-10) and XK (2003-08), Land Rover Discovery/LR3 (2004-11) and Range Rover and Range Rover Sport (2006-10). It is also listed for some 3 Series (2005-11) and X3 (2006-07) cars, but many smaller-engine BMWs in those years used the lighter 6HP19 or 6HP21, which take different parts. Read the ZF tag on the case to confirm a 6HP26, or send us your year and VIN. More parts for these units are on our ZF 6HP collection.

Install notes

• Lube every seal with ATF or assembly gel, size the Teflon rings before sliding drums over them, and air-check each circuit before the mechatronic goes back on.
• On BMWs, replace the mechatronic connector sealing sleeve with the pan gasket. BMW's bulletin calls for sleeve 24 34 7 588 725, a clean, oil-free gasket groove, and the connector seated within 3 mm of the case.
• Inspect the bushings while the unit is apart. Jaguar Land Rover bulletin JTB00305NAS1 traced 6HP26/6HP28 ratio and solenoid codes to degraded lead-free bushes.
• If the solenoids are tired, change them while the valve body is out with our seven-piece 6HP26 solenoid kit.
• Refill with ZF LifeguardFluid 6, which ZF specifies for the BMW, Jaguar, Land Rover and Hyundai 6HP26. Fill until it runs out of the fill hole, cycle the selector at idle, and set the level at 30-35 C oil temperature.

Does this 6HP26 kit include clutches or steel plates?

No. It is the gasket and seal set only: gaskets, lip seals, O-rings and sealing rings. If your frictions are worn, choose our 6HP26 kit that includes friction plates.

Will it fit my BMW 3 Series or X3?

Only if that car has a 6HP26. Many 2005-2011 3 Series and 2006-2007 X3 models used a 6HP19 or 6HP21, which need different seals. Check the ZF tag on the case or send us your VIN.

Is the mechatronic connector sleeve the cause of my BMW leak?

Often. BMW issued a bulletin for oil leaking past the connector sleeve into the plug. The fix is a new sleeve fitted with the pan gasket and a connector seated within 3 mm of the case.

What fluid should I use after resealing a 6HP26?

ZF LifeguardFluid 6 for BMW, Jaguar, Land Rover and Hyundai 6HP26 units. Set the level correctly with the overflow method and the oil at 30-35 C.

Should I reset adaptations after a reseal?

Yes. Clear the transmission adaptations with a scan tool once the job is done, then drive through all gears so the control unit relearns clutch fill times with the new seals holding pressure.

• ZF 6HP Rebuild Cost
• ZF 6HP BMW 5 Series Common Problems
• ZF 6HP Jaguar Common Problems
• ZF 6HP Pressure Control Solenoid Symptoms