[manishk83]

Originally Posted by R2D2

How much of your driving is in the city and on the highway?

I'd suggest following M&M's advice. If they believe the engine would do better with a more frequent oil change given your spirited driving style, especially in the city, please change the oil more frequently. Although modern synthetics can easily take higher loads and temperatures I'd reckon the manufacturer knows their engine best.

Almost all my driving is on expressways and open freeways (within legal speed limits - I tend to use the manual shifters and don’t use the 6th gear which keeps the engine peppy at all times), barring a small 10 km commute to the office - 4 days a week. I have driven 4300 kms in the first month - 500 kms of which would have been city driving.

As a compromise, I was planning on an oil change at 7500 kms.

There was another thought. I saw in your post earlier, that highway driving is not as strenuous on the engine. Plus, it would feel weird getting the 1st major service done within 6 weeks of purchasing the car.

You are right - the manufacturer knows their engine best. But they also tend to put in a lot of disclaimers to avoid warranty claims, were it to occur.

[Bsilver]

Originally Posted by manishk83

As a compromise, I was planning on an oil change at 7500 kms.

There was another thought. I saw in your post earlier, that highway driving is not as strenuous on the engine. Plus, it would feel weird getting the 1st major service done within 6 weeks of purchasing the car.

Manufacturer suggest 10,000kms but that is usually suggested as an overall picture to the market they cater. For example, VW suggests 15,000kms but the conditions in our country are not ideal, having high temperatures, fuel quality, and overall it should not be considered as an ideal condition. Check your oil, if you feel it is in a really bad shape then go ahead to M&M and get it changed. A doubt about the engine oil in mind is better to be sorted by changing the oil, than to have some fault coming up later since you wanted to follow the manufacturer's schedules. Highway driving is mostly at a range of RPMs and many people tend to cruise in a higher gear, this in turn leads to the engine not running at varied RPMs for a long duration of time. This however does not happen in city and a varying load of RPMs are there. However there are mixed thoughts of many on this topic, because highway driving can also be spirited which will put load on the engine.

Happy Motoring!

[Jeroen]

Originally Posted by manishk83

, that highway driving is not as strenuous on the engine..

Well, there are some thoughts about it. What is true is that highway driving doesn’t require much power. E.g. if you have a mid sized car with say 100HP, it might take about 35HP to maintain a steady 100 km/h.

It’s acceleration that requires a lot of power and torque.

A more interesting question would be: which driving conditions give the least wear? Which is quite a tricky question.

Driving with the engine still below normal operating temperature is the worst. Primarily because the lub oil won’t adhere to the cilinder walls. So during those first 5-10 minutes, having started from cold, is when your engine wears most.

It’s the primary reason why cars that are used for short trips only, usually end up with more engine wear.

But what about when the engine is at normal operating temperature. The main issue with highway driving is that because the engine is not working very hard the piston rings don’t get pushed as hard against the cilinder liner.

Piston rings seal not due to mechanical spring force, but due to the high pressure of the mixture. Inside the cylinder pressing at the back of the rings.

Engines with worn piston springs and or worn cilinder walls, tend to use more lub oil on the highway then in start stop traffic!

Although the higher combustion pressures press the piston rings with more force against the cilinder wall, that doesn’t automatically mean more wear.

Engine RPM is another interesting factor on engine wear. Again low RPMs are not necessarily better for your engine than high rpm.

Car engines are designed to work under varying conditions. Other than ensuring you don’t rev the engine to much, or load it up, whilst still below normal operating temperature, there is nothing that you as a driver can do, or should be doing that is likely to have a meaningful impact on engine wear.

(Obviously, you need to maintain the engine).

It is different for larger engines, such as maritime applications, ships and so. Certain engines might get designed specifically for certain operating conditions. E.g. a tug needs to be able to idle for long periods of time, but also go to full power immediately and maintain that for a long period.

A container vessel is designed to run at a given cruise speed and the engine will be designed not only to provide the optimal fuel efficiency, but also the least wear.


Jeroen

[R2D2]

Originally Posted by manishk83

As a compromise, I was planning on an oil change at 7500 kms.

@Jeroen has explained it beautifully in his post on highway running and other factors affecting wear even in marine engines.

An oil change earlier than the specified interval will not harm the engine and is probably good given relatively harsh driving conditions in this country. But it's not considered wallet friendly or environment friendly. Hence the move by most car makers to long(er) drain intervals.

If you have to 2nd guess the car or engine maker move to shorter intervals i.e. change it early if you have to but not a longer drain interval. I would not extend it to beyond what is specified in the car manual regardless of what the oil manufacturer says.

For e.g. I use Amsoil Signature 5W-30 in my petrol car (they also have a diesel engine oil) and while Amsoil says its good for 25K miles but there is a caveat..the running is expected over 1 year or whenver your car owners manual or the MID says you must change the oil. My car has a drain interval of 12 months and I change the oil without having done even a small fraction of the 25K miles the oil is capable of running.

[manishk83]

Originally Posted by R2D2

@Jeroen has explained it beautifully in his post on highway running and other factors affecting wear even in marine engines.

An oil change earlier than the specified interval will not harm the engine and is probably good given relatively harsh driving conditions in this country. But it's not considered wallet friendly or environment friendly. Hence the move by most car makers to long(er) drain intervals.

Absolutely! Thank you both for clarifying. Yes, 6L of engine oil being disposed/ recycled is absolutely not environment-friendly. I don’t plan on doing that unless necessary.

I’ll do the logical thing recommended - hop down to a Mahindra Service Centre this weekend and have them inspect and decide whether the oil is good for another 5000 kms.

PS: I have always changed engine oil at 8k-8.5k mark on my previous Ford - which I drove equally spiritedly. If I had not bothered to read the Mahindra Ops manual, I’d never have known that revving a DSL above 3200 rpm frequently is a stress on the engine. Sometimes, knowing ‘too many things’ is also not the most fortunate of occurrences!

[R2D2]

Originally Posted by manishk83

I’ll do the logical thing recommended - hop down to a Mahindra Service Centre this weekend and have them inspect and decide whether the oil is good for another 5000 kms.

The only way to scientifically judge whether the oil is good or past its service life is to get it analysed by a lab. Most mechanics take a drop of oil from the dip stick and rub it between their fingers to come up with a good or bad rating. It is about as scientific as trying to gauge tyre pressure by thumping or kicking the side wall of your tyre.

PS: I have always changed engine oil at 8k-8.5k mark on my previous Ford - which I drove equally spiritedly. If I had not bothered to read the Mahindra Ops manual, I’d never have known that revving a DSL above 3200 rpm frequently is a stress on the engine. Sometimes, knowing ‘too many things’ is also not the most fortunate of occurrences!

As far as possible with diesels it's important to keep the engine in its sweet spot in the RPM band which varies from engine to engine. Unlike a petrol engine do not try and red line a diesel. It is not meant for that type of spirited driving. Keep engine RPM in its recommended band at all times.

What Ford did you have a petrol or diesel?

[manishk83]

Has anyone explored using 5W-40 on a Turbo Diesel when 15W-40 is recommended, especially those in North India? 5W helps during cold starts and I read that the high temperature performance is similar.

With winters approaching and a visit or 2 planned to Himachal and Kashmir - I was wondering if it’d make better sense for my Scorpio-N?