4AT vs CVT: Two steps forward, one step back?

Another update is upon the Proton Persona and Proton Iriz. The two were spotted testing with camouflage, which suggests cosmetic updates, and we had a peek into the 2021 Proton Persona’s interior.

Floating infotainment screen aside, one of the speculations is the change from CVT to a 4-speed automatic (4AT). This has sparked conversations amongst readers. Some are all for it, some against it.

Why a 4-speed automatic and not 6-speed?

Simply put, it’s cost. Using a never-before-seen transmission in Proton would mean more unique parts, which would lead to higher manufacturing cost.

The Hyundai-sourced 4-speed automatic (assuming this eventually makes its way into the 2021 Proton Persona and Iriz) is currently deployed in the 2019 Proton Saga facelift. Using this transmission would reap the benefits of greater economies of scale.

Is the 4-speed automatic better than CVT?

We’ll take the 2019 Proton Saga facelift as reference and like always, there are pros and cons. For day to day driving around town, yes, it is better.

The Punch-sourced CVT has an inherent jerkiness that no matter the calibration (newer variations are improved), taking off from standstill in a seamless manner is a hit or miss exercise.

You’d have to adapt your driving style to the transmission by allowing the clutch to hook up, then gently apply throttle. Also, there's an audible whine from the CVT during hard acceleration or when reversing.

In the 2019 Proton Saga facelift, there are no such issues. It provides a driving experience most are accustomed to – a good old 4-speeder with leisurely gear-shifting speed.

Granted, it can feel lethargic at times. This can be attributed to the calibration to maximise fuel efficiency. One workaround is to put the gear lever into “S” position to make it more responsive and more eager to rev.

The advantage of CVT comes to play when on the move. It keeps the engine spinning at its peak powerband with no shift shock, just constant acceleration.

How about fuel efficiency?

Proton claims a fuel consumption figure of 6.7-litre/100 km for the 2019 Proton Saga, while the pre-facelift model with CVT had a claimed figure of 5.6-litre/100 km.

In practice however, the difference isn’t as pronounced as the official figures. Owners of the pre-facelift Saga have reported fuel consumption figures of around 6.0- to 6.3-litre/100 km. And the claimed 6.7-litre/100 km in the 2019 Proton Saga is very much achievable, as yours truly has one in the family.

That being said, a CVT is theoretically more fuel efficient than a 4-speed automatic due to the wide spread of ratios.

Which is cheaper to maintain?

Cost of service between a CVT equipped Saga and a 4AT Saga is identical at every interval. That is, until the 60,000 km/36-month mark when a transmission fluid change is due.

CVT fluid costs to RM 165.03 and transmission oil filter costs RM 156.12, both amount to RM 321.15. As for the 4AT, fluid costs RM 220.18 but no filter change is required, which is ultimately cheaper to service than the CVT.

Conclusion

Going back to a 4-speeder may seem like a step backwards, but considering the resources, price point as well as feedback from customers on the CVT, it’s a logical choice for Proton to make. It's more refined at low speeds and isn't too costly to implement.