Current
ZF 6HP, 8HP and 9HP gearbox repair
Between them, the ZF 6HP, 8HP and the transverse 9HP are fitted to more premium cars in Britain than anything else. On the whole they’re excellent gearboxes. What they don’t like is age, heat and never having their fluid changed, and when they go wrong, they go wrong in the mechatronic unit far more often than in the gear train.
12 month warranty
Fill-for-life is a marketing term
ZF nominally builds these as fill-for-life. In practice the fluid degrades, and by 80,000 miles it’s usually visibly past it. A fluid and filter service at sensible intervals is the cheapest thing you’ll ever do to one of these boxes.
The two faults we see most are the mechatronic sleeve and bridge seal leaking, which drops line pressure and gives you harsh shifting, flare and eventually limp mode, and torque converter lock-up shudder, which most people describe as driving over rumble strips at about 40 mph on light throttle. Both are repairable without a new gearbox.
BMW owners: the “Transmission malfunction, drive moderately” message is the car protecting itself. It is not a death sentence. Get it read before anyone quotes you for a replacement unit.
ZF 6HP
The 6HP19, 6HP21, 6HP26, 6HP28 and 6HP32 are fitted across BMW, Land Rover, Jaguar, Audi, VW and others from the early 2000s. The parc in Britain is enormous and the mechatronic sleeve leak on this family is arguably the single most common transmission fault on UK roads.
Typical applications: BMW 3, 5, 6, 7 Series and X3 and X5; Range Rover L322 and Range Rover Sport L320; Jaguar XF, XJ and S-Type; Audi A6, A8 and Q7; VW Touareg; Ford Falcon.
ZF 8HP
| Variant | Torque | Typical applications |
|---|---|---|
| 8HP45 / GA8HP45Z | approx. 450 Nm | BMW 3, 4 and 5 Series; Audi A6 and A7; Jaguar XE and XF |
| 8HP50 | approx. 500 Nm | BMW, Audi |
| 8HP55 | approx. 550 Nm | Audi, Porsche |
| 8HP65 | approx. 650 Nm | BMW, Land Rover |
| 8HP70 / GA8HP70Z | approx. 700 Nm | BMW 5, 6 and 7 Series, X5, X6; Range Rover, Range Rover Sport, Discovery; Jaguar F-Type |
| 8HP75 / 850RE | approx. 750 Nm | Jeep, Ram, Chrysler, Maserati |
| 8HP90 / 8HP95 | approx. 900 Nm and above | BMW M, Range Rover SVR, Bentley, Rolls-Royce, Aston Martin |
Scroll the table sideways to see every column.
ZF 9HP
The transverse nine-speed, and a different animal from the longitudinal 6HP and 8HP despite the family name. It is the gearbox in the Range Rover Evoque and Discovery Sport, and in the Jeep Cherokee, Renegade and Fiat 500X.
Most of what owners complain about on these is shift quality rather than a broken part: hesitation, a shunt on light throttle, or reluctance to pick a gear at low speed. A great deal of that has been addressed by ZF and the manufacturers through software, so the first question on a 9HP is always what calibration it is on. We check that before quoting for anything mechanical.
ZF 9HP applications
| Vehicle | Notes |
|---|---|
| Range Rover Evoque | L538 and L551 |
| Land Rover Discovery Sport | L550 |
| Jeep Cherokee | KL |
| Jeep Renegade | |
| Fiat 500X |
Scroll the table sideways to see every column.
Common faults
| Symptom | Likely cause | Codes commonly seen | Our fix |
|---|---|---|---|
| Harsh or delayed shifts, then limp mode | Mechatronic sleeve or bridge seal leak dropping line pressure | P0700plus manufacturer-specific | Sleeve and seal renewed, mechatronic rebuilt, adaptations reset |
| Shudder or vibration at 40 to 50 mph on light throttle | Torque converter lock-up clutch | P0741 | Torque converter rebuilt and balanced, fluid renewed |
| “Transmission malfunction, drive moderately” on BMW | Several possible causes. Needs reading, not guessing | manufacturer-specific | Full diagnostic and live data before any quote |
| Flare or slip between ratios | Clutch pack wear, low line pressure | P0729 to P0736 | Pressure test, then rebuild as required |
| Won’t come out of Park | Park lock actuator or mechatronic fault | — | Actuator and mechatronic assessed |
| Fluid leak at the sump or the electrical connector | Sump pan gasket, mechatronic sleeve, connector seal | — | Sump, gasket, sleeve and connector renewed |
| Dark, burnt-smelling fluid at 80,000 miles and up | Fluid degradation | — | Fluid and filter service, before it becomes a rebuild |
Scroll the table sideways to see every column.
code a stored fault code. software a calibration or coding action. — no code typically logged.
What we do
Mechatronic remanufacture including the sleeve and connector seal. Valve body rebuild and solenoid replacement. Torque converter rebuild and balancing. Full gearbox rebuild. Fluid and filter service to the correct specification and fill temperature. Adaptation reset and road test.
What will it cost?
We price a mechatronic sleeve and seal repair once we know which unit you have and what it is doing. Send us the gearbox number and the symptoms and you will have an answer the same working day, with an indicative price wherever we can give one.
Frequently asked questions
Is it really fill-for-life?
No. We’d suggest a fluid and filter service around 60,000 to 80,000 miles.
My car is in limp mode. Can I drive it?
Gently, and briefly. Get it read before you do anything else.
Is the shudder at 40 mph serious?
It’s the torque converter lock-up clutch. It won’t strand you tomorrow, but the debris it generates circulates through the valve body, so it gets more expensive the longer you leave it.
Can you do the sleeve without dropping the box?
In most cases, yes.
Related
How it works
Sending us a unit
You don’t need to bring the car. Most of what we do arrives on a pallet.
- Drain it. Couriers won’t take a unit full of oil, and it’ll leak.
- Crate or pallet it. A gearbox needs to be strapped to a pallet or in a stout crate. A cardboard box won’t survive.
- Label it. Put your name, telephone number and the vehicle inside the packaging as well as on it. Labels come off in transit.
- Tell us it’s coming. Send the enquiry form first so we know what to expect and can book it in.
We can arrange collection anywhere in mainland UK. Ask when you enquire.
What happens next
- 01You send the enquiry.
- 02We come back the same working day with an initial view and, where we can, an indicative price.
- 03If it needs looking at, we book it in or arrange collection.
- 04We strip and assess, then ring you with a firm price before any work goes ahead.
- 05Rebuilt, tested, returned, warranted for 12 months.
No work happens without your say-so, and there are no surprises on the invoice.
Same working day
Send us the number and what it’s doing
The gearbox number, the vehicle and the symptoms. That is usually enough for a straight answer, and photographs are welcome.