On 13 December 2019, the first 2020 Proton X70 rolled off the production line in Tanjung Malim, exactly one year and one day after the SUV was introduced in Malaysia. Malaysia’s best-selling C-segment premium SUV is now proudly locally-assembled, with the CKD variant set for the official launch soon.
While retaining the tried-and-tested 1.8-litre turbo gasoline direct-injection (TGDi) powerplant, the old six-speed slushbox is replaced by the new 7DCT—a state-of-the-art seven-speed wet dual-clutch transmission.
Here are some things you need to know about the Proton X70’s new transmission.
Who made this gearbox?
The new 7DCT was co-developed by Geely and Volvo. The cutting-edge transmission is found in a variety of Geely and Lynk & Co models. Usually mated to Geely’s new 1.5-litre turbocharged three-cylinder engine, it has found its way into the Geely Boyue Pro, the upgraded Boyue model (Gen. 2) which the Proton X70 is based upon. The gearbox is also found in the Volvo XC40 T5 Twin Engine PHEV.
The 7DCT replaces the six-speed torque converter auto box built by Geely-owned Drivetrain Systems Internation (DSI).
So, why the new dual-clutch transmission as opposed to a regular slushbox?
In essence, a DCT is a robotised manual transmission. It uses two clutches to engage odd and even gears. There’s a set of actuators that engage and disengage gears at hundreds or tenths of a second. A DCT will shift gears faster than any driver who shift with a manual gearbox.
Now that we have that cleared; Geely’s 7DCT is super-efficient. Class-leading efficient in fact. Benchmarked against Volkswagen’s dry clutch DSG transmissions, the 7DCT delivers an overall efficiency figure of 94.6 percent, with a maximum figure of 97 percent. That makes it as good as a manual gearbox, with minimum drivetrain losses. It also makes it one of the most efficient gearboxes in the world.
What does high-efficiency mean?
Well, for one, because there’s less drivetrain losses, hence, will offer better power delivery and fuel consumption. Unlike an auto transmission, there’s no slip from the torque converter and no losses from driving a hydraulic pump (that operates various clutch packs).
And this shows on official quoted numbers. Compared to the previous generation Boyue which uses the six-speed auto box, the 7DCT-equipped Boyue Pro returns 7.5 litres per 100km as opposed to 7.8 litres per 100km on the previous generation. Theoretically, the 2020 Proton X70 should offer these improved fuel efficiency numbers as well.
The new 7DCT is also lighter, tipping the scales at 75kg (compared to 98kg of the six-speeder), delivering some weight savings to the CKD Proton X70 overall.
Why a wet clutch and not a dry clutch like VW’s DSG?
While dry clutch DCTs are inherently more efficient, they’re also prone to premature wear and breakdown over time—much-publicised issues that have plagued automakers like VW (in early iterations). Dry clutches are also known to be sensitive to changing weather conditions.
The wet clutch is more robust and durable as it constantly oil-cooled when in operation—between 12 and 15 litres of low-viscosity transmission fluid is fed to the innards every minute. Ultimately, keeping it well-oiled ensures its longevity.
Geely is confident of its seven-speed wet clutch transmission and says it conforms to Volvo’s strict durability requirements. The transmission is designed for a service life of more than 350,000km, significantly higher than the industry standard of 240,000km.
According to Paul Tan who visited Geely’s headquarters in Zhejiang, China recently, the China automaker had extensively tested the DCT under numerous hot and cold weather as well as high-altitude conditions across China, South Africa and Europe, clocking over nine million kilometres.
The gearbox comes with a shift-by-wire electronic gear lever and paddle shifters. It is unclear if the 2020 Proton X70 will have gear shifters as found on the Boyue Pro, seeing that the current CBU models offer these.
Official shifting speed is said to be as quick as 0.3 seconds.
The new 7DCT and 1.8-litre TGDi combo releases an additional 15Nm from the powerplant, bringing torque up to 300Nm, available slightly higher up the range at 1,750-4,000rpm. Power figures remain unchanged at 181hp at 5,500rpm.
With slightly more torque, the Proton X70 will likely benefit from better acceleration and a better overtaking experience, although this remains to be seen in real world application.
PROTON is set to launch the locally-assembled 2020 Proton X70 soon, and I’m eager to see how the new car performs as compared to the fully-imported version.