I am planning to buy the Renault Triber but I understand its engine crank case/sump is made of plastic instead of metal. I have also come across some reports of such plastic sumps getting damaged due to potholes or speed bumps. How reliable and safe is this material for such a critical and high temperature application?
Ashutosh Tiwari, Mumbai
The use of materials such as specially-engineered plastics and polyamides in critical applications, for instance, the engine oil sump in the Renault Triber, is an endeavour of automakers to reduce the overall weight of cars. As a result, the term ‘lightweighting’ is popularly used within the industry in this regard.
Such materials could offer potential weight savings of up to 50% of a component’s original weight, which is quite substantial. While plastic might look inferior in strength compared to metals such as aluminium, these specific materials are carefully engineered and tested to offer a high thermal resistance to the oil’s temperature, as well as resistance to impact from curbs, stones and even if the entire engine drops.
Some of these materials are glass reinforced and heat stabilised to offer very good flow properties for optimum heat dissipation. They also undergo rigorous testing before being approved for implementation in critical components in road-worthy vehicles that are to be mass produced.
These tests ensure the sump can bear stone and gravel-chip impacts as well as high operating temperatures throughout the life of the vehicle, so as to cause no failures. Since you are inclined towards the Renault Triber, we suggest you don’t let the material of the sump guard influence your decision.
Style Vs Space
We would like to buy a new luxury car priced around ₹ 70-90 lakh and have shortlisted two cars — the BMW X5 40i M Sport and the Range Rover Velar 2.0 petrol. Priorities are comfort, performance, good road presence and a good resale value after a few years. Or would you suggest we go with a used Mercedes or BMW flagship model instead?
Shourya Reddy Pasnoor, via email
The Velar and X5 are very different cars. If you are looking at style and a bit of class, the Velar, with its gorgeous design and well-appointed interiors, will be the one that turns heads more.
However, the X5 is a better car overall. It is more spacious and nicer to drive, thanks to a stronger engine range. The X5 has good road presence too but has a more conventional shape and is nowhere near as masterfully designed as the Velar.
Hormazd Sorabjee is the editor of Autocar India. Mail your feedback and queries to email@example.com