Third gear slipping.
P0733 — also written PO733, P 0733, 0733 — is the OBD-II code for gear 3 incorrect ratio. Same code, same fix: this page covers every spelling of it.
Your gearbox and the engine have had a falling out—specifically, the transmission is spinning slower than it should be in 3rd gear, usually because the internal clutches are slipping. Very common on high-mileage BMW 3 Series and older Vauxhall automatics.
P0733 is a transmission fault code, typically costing £250–£2500 to put right in a UK garage.
What P0733 actually feels like to drive
- The car feels like it's 'flaring'—the revs jump up like you've dipped the clutch during the 2-3 shift.
- Total loss of drive when the box tries to hit 3rd, followed by 'Limp Mode' or 'Transmission Service Required' on the dash.
- A violent 'thud' or 'clunk' when accelerating onto a dual carriageway.
- The car pulls away fine, hits 2nd, then just sits in a neutral-like state while the engine screams.
- Works perfectly fine when the gearbox oil is cold, but starts slipping as soon as you've done 10 miles.
What causes P0733?
- Worn clutch
- Solenoid
UK vehicles that throw P0733 most often
- BMW 3 Series (E90/F30) ZF 6HP/8HP 2006-2015
- Vauxhall Insignia 2.0 CDTi (AF40 Box) 2008-2017
- Land Rover Discovery 3/4 (ZF 6HP26) 2005-2016
- Ford Focus 2.0 TDCi (Powershift DCT450) 2011-2018
- Volvo XC60/XC90 (TF-80SC Box) 2008-2014
- Jaguar XF 3.0D (ZF 6HP28) 2009-2015
How P0733 is fixed
- Solenoid or rebuild
The P0733 misdiagnosis that wastes money
I see people rushing to the local factors to buy a new shift solenoid thinking it's an easy electrical fix. On the ZF and Aisin boxes we see in BMWs and Volvos, it’s rarely just a solenoid. Nine times out of ten, the TCU has detected the engine RPM and output shaft speed don't match because the friction plates are burnt to a crisp or a seal has perished internally. Swapping a £60 solenoid into a box with black, burnt-smelling ATF is just throwing good money after bad. Check the fluid colour first—if it looks like Guinness, the box is toast.
What a UK garage should charge for P0733
If you're lucky and it's just a solenoid block or a major service, you're looking at £250-£450 using decent Febi or ZF fluid. But if the friction plates are gone, a local specialist will charge £1,500 to £2,500 for a full bench rebuild including a new torque converter. A main dealer won't even fix it—they'll just quote you £5k+ for a crate engine and box. Diagnostic time at a proper indie should be about £80-£100 to get the live data logs.
P0733 repair cost in the UK
Most P0733 repairs land between £250–£2500 including parts and labour. The spread is wide because the cheap fix (a sensor, a hose, a leak) and the expensive fix (a major component) throw the same code — which is why a proper diagnosis before parts are bought saves the most money.
Bob's tip on P0733
Before you let a garage quote you £2k for a rebuild, ask them to perform a 'Transmission Adaption Reset' and check for software updates. Sometimes, especially on the VAG DSG boxes or the Ford Powershift, a software glitch makes the timing wonky. If you're buying a used car and the owner says 'it just needs a sensor,' walk away. A P0733 is a 'box-out' job most of the time. Insist on a stall test and a fluid sample check—if there’s glitter in that oil, it’s a mechanical obituary.
Can you drive with P0733?
Book in.
Urgency: high.