What Happens If You Use BS-6 Fuel In BS-4 Cars?

by Mohit Bhardwaj | 28/10/2019
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With BS-6 emission norms kicking in, BS-4 fuel will soon stop being sold by fuel stations, in order to be replaced by BS-6 fuel. This transition has invited a lot of confusion among the existing car owners and new BS-4 car buyers. We explain further about the consequences of using BS-6 fuel in BS-4 cars.

The soon-to-be regulated BS-6 emission norms have a lot of technical and compositional modulation on their side. But keeping that aside, it has adorned all the limelight that any emission norm standards ever could. With that said, it has and will affect the entire auto industry in some way or the other. With these new norms, what’s about to be regulated is BS-6 fuel. No, it isn’t jet fuel but it will comprise of a different chemical composition and properties in comparison to the currently available BS-4 fuel. However, we understand that by know there would be a lot of questions in your mind. Should you plan to keep your BS-4 car with you forever or rather planning to buy one with heavy discounts against an expensive BS-6 car. And, how will you do that with BS-6 fuel? Well, do not be worried about it at all. We’ve got everything compiled up for you, just to ease out the transition process from BS-4 fuel to BS-6 fuel.

Also Read - BSVI Vs BSIV: All Your Questions Answered.

BS-6 Fuel In BS-4 Car

What’s the difference between BS-4 and BS-6 fuel?

The BS-6 fuel as such, does not have much change on its side. The reduced Sulphur content is the major difference that will change the compositional aspects of the fuel. The BS-6 fuel will have just 1/5th of total Sulphur content present in the BS-4 fuel. With this reduction, the actual quantity will come downto just 10PPM from 50PPM. This has been to done to make sure that BS-6 cars have reduced SOx emissions.

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Will it affect the engine and its part?

The BS-6 fuel with just 20% of the actual Sulphur content of BS-4 fuel, will possess lower lubrication qualities. The Sulphur in the fuel is added to improve its lubrication qualities and that its flow doesn’t affect the mechanical components of the engine. Fuel starts its journey from the fuel tank to the engine through a series of lines, pumps, filters, and then injectors. With reduced Sulphur content going to the the injectors in a diesel engine, it is bound to wear out prematurely. However, BS-6 engines will be designed per BS-6-spec fuel, but BS-4 vehicles with the upgraded fuel, will face wear issues in the long run. But such problems will start arising only once the vehicle has been used for almost a lakh kilometres.

BS-6 fuel in BS-4 car.

How to reduce problems associated with the use of BS-6 fuel in BS-4 cars?

The human race is best at finding solutions once the threat of the problem becomes too great, and so is the case with this issue. BS-6 fuel can or should only be used with additives in a BS-4 car. The only issue associated with the use of BS-6 fuel in a BS-4 car is the chemical lubrication through Sulphur. However, there are additives available in the market to improve the lubricating properties of the fuel and they can be used to reduce the wear and tear of any engine’s mechanical components. These synthetic lubricants have been available in the market for quite some time now, and there are bound to be more lubricant manufacturer stepping in to explore this area of opportunity. However, one should understand that any of such flaws with use of upgraded fuel is only expected in the long run, which means they’ll only start showing their true effect after a Lac km or so.

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Will using BS-6 fuel in BS-4 car reduce mileage?

A negligible drop in the mileage is bound to be expected with the use of cleaner fuel in an old car, as a result of the drop in thermal efficiency. The drop is so small though, it comes up to just around 2% reduction in the overall efficiency of the vehicle. But, this is the price you pay for buying a vehicle compliant to old emission norms at a lower price. So compared to the price you pay to buy a BS-4 car with a little less mileage, the higher priced BS-6 cars can theoretically go 0.1 km extra on the same amount of fuel. However, in practicality, there would be no reduction in the fuel mileage.

Where and how it will be available?

BS-6 fuel is already on sale in NCR through IOCL, BPCL, and HPCl fuel bunks. By April 2020, it will be available throughout the country, given the mandate for the BS-6 emission compliance. From April itself, BS-4 fuel will stop being sold at fuel stations in order to make way for BS-6 petrol and diesel fuel only.

Also Read - BSVI Fuel To Get Ready Across Delhi NCR.

BS-6 fuel is available on the regular pumps and will replace the BS-4 fuel by coming april 2020.

Will it be any more expensive to use BS-6 fuel in BS-4 cars?

As we mentioned earlier, the BS-6 fuel is already available in markets like NCR and a few other major metro cities around the country. The cost of both BS-6 and BS-4 petrol and diesel will remain the same. Thus, we believe it won’t be any more expensive to buy in comparison to BS-4 fuel.

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With all the aspects taken into consideration, we can safey say that BS-6 fuel can in fact be used in a BS-4 car with just a little more care and caution. By using synthetic additives to improve the chemical lubrication calibre of the fuel, any BS-4 car can last long without any major downsides. This solution will have to be adopted since there isn’t much being modulated by the government when it comes to BS-6 fuel.

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