Proton’s Thinking Outside The (Gear)Box

If it ain’t broke, Proton will still fix it and make it better… which is what they did for the locally-assembled X70

  • By: Dinesh
  • Friday, 14 February 2020
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Proton’s Thinking Outside The (Gear)Box

So, the Proton X70 is finally, officially, irreversibly and irrefutably assembled locally now. Not much has changed with the exterior but as you may have heard, Proton thought outside the box to improve fuel efficiency and maximise performance with an all-new transmission.

Proton however are more inclined to refer to it by its model year; 2020 X70, instead of its assembly locality. That’s fine because modern vehicle assembly produces no discernible disparity in build quality.

That’s not what we’re about to harp on about though. The most significant enhancement to the X70 will come in the form of a new in-house, seven-speed dual-clutch transmission that replaces the automatic six-speed from the initial imported batch.

Now we know, the words “dual” and “clutch” don’t mean much but compound them and you instantly strike fear into the hearts of potential carbuyers. To dispel that, Proton brought a few journalists to its Chunxiao plant located at Ningbo, Zhejiang in China to observe the manufacturing process and build quality.

Now we’re sure you’ve got plenty of questions about the switch and the reason behind it as well as its durability. So, we’ve pieced together a little FAQ.

1. Please don’t bluff. The saying goes “If it ain’t broke, don’t fix it.” So, why did they change it then? Surely something wasn’t right?

Yes, you’re right about the saying but nothing else really. Sometimes; and especially in the ever-competitive automotive industry, if there’s even minute room for improvement carmakers will pounce on it.

The main reason for the switch is that globally, Geely group is making a transition to the wet seven-speed dual-clutch transmission. Why you may ask? Well, it’s simple. Efficiency. Moving ahead, the 7DCT will be the long term and primary transmission for the group.

Over the trip, we got to learn and observe the manufacturing process and the high standards adhered to behind it that includes shot peening internal components; a cold working process done to induce a residual compressive stress which improves resistance to fatigue and stress corrosion cracking on stressed components.

If anything, it demonstrates that Geely and Proton are aiming high with their products and firmly have the continental vehicles in their crosshairs.

2. I was expecting more. Is that the only change to the CKD Proton X70 though?

Mechanically, yes. But it’s a significant improvement with plenty of long term ownership benefits, chiefly improved fuel efficiency. Don’t forget the ventilated front seats, the handsfree powered tailgate and the slightly revised damping.

3. What exactly are the differences between the old and new transmission?

Glad you asked. For starters, they’re fundamentally different in that the previous one was a traditional automatic with a torque converter while this new one is a dual-clutch unit.

Efficiency is one of the gains, as are quicker shift times. A dual-clutch is essentially having two transmissions in one case. The odd numbered gears have their own clutch and the even ones their own. While the car sets off in first gear, second is already preselected and can be switched over in as little as 0.3-second when required. Same applies to downshifts. Hence, power loss between gear changes is minimised for a smoother drive.

4. Eh, you said dual clutch transmission. Haven’t we heard that term before? Wasn’t there a lot of, erm… problems with it? Can trust or not?

We know certain marques have had nightmares with their dual-clutch transmissions but fortunately they’ve learnt from their mistakes and rectified the issues. Dual-clutch transmissions are the default box of choice now for the likes of Volkswagen, Audi and Porsche that use them extensively in most of their models.

Geely however is keen to emphasise that it went above and beyond in development and testing of its 7DCT to ensure that nothing like that debacle repeats itself and that buyers will reap all the benefits without any of the drawbacks.

5. So, this new dual-clutch transmission from Geely is better in all aspects, right? Did they test the living hell out of it or not?

For starters, Geely’s 7DCT is a wet clutch type that’s inherently more reliable and robust. Extreme weather testing was conducted as per norm in the heat of the Turpan, China, Alice Springs, Australia and South Africa whereas frigid temperatures were bombarded on in Colmis in Sweden and Yakeshi in China. They even ascended to high altitudes in the Kunlun Mountains and the Italian Alps. All in, the 7DCT clocked in over nine million kilometres in testing. In layman’s terms, that’s just short of 12 rounds trips between Earth and the moon.

Evaluations also included robust testing comprising towing a 1.8-tonne load on a 12 per cent incline multiple times, back to back. This test mule begins moving with said load on the incline, coming to a stop then moving on again. The 7DCT never overheated or experience a decline in performance.

A large part behind the lack of heat soak that drains performance is the dedicated cooler and on-demand oil pump that circulates 12 to 15-litre of transmission fluid every minute.

Furthermore, Geely’s 7DCT conforms to Volvo’s stricter durability requirements that necessitates a service life of over 350,000km as opposed to the the industry standard of 240,000km.

Lastly, Tejinder Singh; Geely’s Senior Chief Engineer, assures us that wet-type dual clutches eliminate most DCT issues such as shudder, judder and wear. So yeah, they did.

6. What are the benefits between this and the old transmission?

We’ve mentioned this before and we’ll say it again. Efficiency. Geely quotes that it benchmarked the 7DCT against Volkswagen’s dry clutch DSG. The 7DCT is more efficient than Volkswagen’s dry DSG and the Aisin eight-speed auto; another fantastic transmission on the market and a staple of BMWs.

Traditional torque converter automatics average less than 90 per cent efficiency whereas the Geely 7DCT averages 94.6 per cent and maxes out at 97 per cent. That’s close to the figures delivered by our favourite conventional, three-pedal manual box. The end result is a slight improvement in fuel consumption from 12.8km/l to 13.3km/l in the 2020 X70.

Additionally, the 7DCT is also roughly the same size of the outgoing six-speed auto; even with an extra ratio, and weighs less too at 75kg.

Lastly, the 7DCT has a higher max torque rating of 330Nm and you’ll see the benefits in the next question.

7. Did they change the engine? Same engine but a different transmission?

Well yes, mechanically the engine is the same but that’s no bad thing. The 1.8-litre turbo four is a Geely star engine from its third-generation engine family. Direct injection is courtesy of Bosch so you know only the best has gone into it. An electric wastegate governs the boost and is capable of producing pressure from as low as 1,200rpm. Geely claims the NVH levels are on par with German engines.

Addressing the prior question, the 7DCT has a higher max torque rating which allowed Proton engineers to free up an additional 15Nm from the engine to bring max torque to a nice, round 300Nm. This places the 2020 X70 as the highest torque in its class (petrol) behind the Mazda CX-5 2.5 Turbo.

8. More importantly, is this going to blow a hole in our pockets or not? Better not be expensive to maintain or I’m going to raise hell on the internet where all my opinions matter.

We feel you on this one but again, Tejinder explained that servicing cost will be comparable to the six-speed auto. In fact, 7DCT uses a proprietary low-viscosity transmission fluid (different from torque converter ATF) and the cost is lower than the ATF used in the six-speed auto X70s. Service intervals are similar as well so you should actually save on not only fuel but maintenance as well.

9. Sounds vaguely convincing. Is this transmission used in any other models?

Darn right it is. As we mentioned earlier, Geely group is staking its future on this 7DCT. Hence, it’s already found in a number of models under the group’s umbrella that includes Geely models with the 1.5-litre turbo three, Lynk & Co and Volvo. The Swede application is in the XC40 range and includes the T5 Twin Engine, meaning it has the electric motor bolted on. If it’s good enough for Volvo, it’s good enough for us.

The 7DCT was designed to be hybrid compatible with the electric motor plugging in directly and not as an afterthought. In hybrid form, the electric motor can run gears 2/4/6/R under pure electric propulsion if certain conditions are met.

10. Actually, when engineers claim that a transmission is this percentage or that percentage better than another, what parameters are they applying to judge that?

That’s something that came up during the trip and the answer might actually astonish you. The Geely engineers explained that the refinement and perception of a great transmission lies in its performance below 50kph. Above 50kph, most transmissions perform and feel the same because momentum is already in motion.

Calibrating a transmission to operate smoothly and in a refined manner under 50kph, is the toughest part of mapping transmissions. As the engineers clarified, performance at slow speeds is how you tell a great transmission apart from a good one.

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