The new Tata Sierra has been drawing plenty of attention for its standout design and smart packaging. Adding to its appeal is a wide range of powertrain options – petrol, turbo-petrol and diesel, spread across a broad price band of Rs 11.49 lakh to Rs 21.29 lakh (ex-showroom).

This article focuses on fuel efficiency, based on real-world testing of the diesel-automatic variant.

1. Diesel-auto gets two drive modes: City and Sport
2. Misses auto engine stop-start

Tata Sierra diesel-automatic real world mileage test

Sierra diesel-AT has an average real world mileage of 13.05kpl.

The Sierra diesel-automatic offers two drive modes – City and Sport – but misses out on features such as an Economy mode and an automatic engine stop-start system. Power comes from a 1.5-litre diesel engine producing 118hp and 280Nm. This is the same unit seen in the Nexon, though output has been increased by 2hp and 20Nm. Another key difference is the transmission – the Sierra uses a 6-speed torque-converter automatic, whereas the Nexon diesel is paired with an automated manual transmission (AMT).

Tata Sierra

₹13.37 - ₹25.28 Lakh (On road price)

Range/Mileage

To be tested

Specifications

Rear Brakes: DiscFront Brakes: DiscBoot Capacity: 622-1257+ 38 more

Features

Auto Parking: NoClimate Control: Auto 2-zoneAmbient Lighting: Yes+ 102 more

Variants

Accomplished Diesel ATAccomplished Diesel MTAccomplished Petrol MT+ 21 more

Despite the absence of efficiency-focused features, the Sierra diesel-automatic delivered an impressive 11.53kpl in city driving when tested in City mode. On the highway, it returned a real-world efficiency of 14.56kpl, a figure comparable to the Tata Harrier, which is powered by a larger 2.0-litre diesel engine.

Autocar India’s fuel efficiency testing

Before our real-world fuel efficiency tests, we fill our test cars’ tanks to the brim and maintain tyre pressures based on the manufacturer’s recommendation. These cars are driven in fixed city and highway loops in and around Navi Mumbai, and we maintain certain average speeds. Throughout the tests, there is only one person in each car, running the air conditioning at 22deg C in full-auto mode, and other electricals, such as the audio system, indicators and wipers, when required, just like a regular user would. Periodic driver swaps further neutralise variations in driver patterns. At the end of each cycle, we calculate efficiency by filling the tanks to full again.