What is a torque converter lock-up kit?
In a standard automatic, the torque converter always allows some slip between the engine and gearbox. Under load (towing a van, climbing loaded, sand work) that slip generates heat and wastes fuel. A lock-up kit lets you lock the converter mechanically when you want to, removing the slip so power goes straight to the wheels and the transmission runs cooler. It suits common-rail diesel 4WD utes and wagons that tow and tour, the core of what we fit. This is part of our transmission services in Adelaide. Tell us your vehicle and how you use it and we will tell you if a lock-up kit is worth it.
Why fit a Stocklock lock-up kit
- Lower gearbox temperatures through reduced converter slippage, the headline win for towing and touring.
- Up to 3 litres per 100km fuel saving when locked up at highway and touring speeds.
- More torque to the wheels, with less lost to converter slip.
- Extended transmission oil life, because cooler oil lasts longer.
- Reduced flaring in the gears and more relaxed drivability.
- Increased engine braking, useful descending loaded or off-road.
- No P-code deletes, no relays, with custom factory-fitting switches so it integrates cleanly.
Australian-made and tested before it leaves the shop
The Stocklock integrates with the vehicle using Pulse Width Modulation (PWM). The PWM power source gives smooth engagement and disengagement and keeps the solenoid cool at all times, with no harsh on/off lock-up that hammers the driveline. It is developed and made in Australia, and every kit is test-driven before it is sold, proven in Australian conditions.
When we fit it, we install it correctly on our own hoist, fit the factory-style switch, and photograph the job and send you the images. We are an RAA Approved Repairer and all our work is fully guaranteed, with a 12-month or 20,000km driveline warranty on the fitting.
Vehicles we fit Stocklock kits to
We fit Stocklock kits to popular Toyota auto 4WDs that tow and run hot: the LandCruiser 200-Series, Prado, Fortuner and Hilux. The kit suits many automatic-transmission 4WDs that tow or carry load, so tell us your vehicle and we will confirm the right kit and fitment. A lock-up kit pairs well with a 4x4 diesel tune and an ECU remap for the full towing setup.
Toyota LandCruiser 200-Series transmission software upgrade
Sick of your 200-Series LandCruiser holding gears and hunting between 5th and 6th? The VDJ200 transmission software upgrade is flashed in for better shifting and improved towing compliance, and pairs naturally with the Stocklock lock-up kit on the same rig. Ask us about 200-Series LandCruiser tuning.
Stocklock pricing
Two ways to buy: $850 supply only to fit the genuine Australian-made kit yourself, or $1,450 supplied and fitted, where we install it on our hoist, fit the factory-style switch, set it up and photograph the job. Free loan cars are available while your vehicle is in for fitting.
Genuine Australian-made Stocklock kit, fit it yourself.
Installed on our hoist, factory-style switch, set up and photographed.
Torque converter lock-up kit FAQs
It lets you lock the torque converter so there is no slip between engine and gearbox under load, which drops transmission temperatures, sends more torque to the wheels and cuts fuel use when you are towing or touring.
Up to 3 litres per 100km when locked up at highway or touring speeds. The real-world figure depends on the vehicle, load and how you drive.
Yes. Reducing converter slip is the main way the kit lowers transmission oil temperature, which also extends the oil's life. It is the headline benefit for vehicles that tow or carry load.
Yes. The Stocklock is $750 supply only. Or we supply and fit it for $1,350, set it up and photograph the job. Either way you get the genuine Australian-made kit.
Popular Toyota 4WDs like the LandCruiser 200-Series, Prado, Fortuner and Hilux, plus many other automatic 4WDs that tow. Tell us your vehicle and we will confirm the right kit.
It uses Pulse Width Modulation for smooth lock-up that keeps the solenoid cool, integrates with factory-style switches and runs no P-code deletes. Fitted correctly it protects the transmission rather than stressing it. All our fitting work is guaranteed.
Yes. The VDJ200 transmission software upgrade improves shifting and towing compliance on the 200-Series (the holding-gears and hunting-between-5th-and-6th issue), and pairs well with a lock-up kit.