Thread: Service interval for TDV6

Originally Posted by bbyer

I assume that you are saying that every 5,000 km, or every few months, you change oil and filters, and as such, the engine is still running well.

That is a testament to the importance of oil changes to engine life. Also, my view is that new filters are probably more important than new oil, at least in dirty dusty conditions.

[snip]


re-read post # 9, you don't have to change the oil frequently for good engine life

On most vehicles the oil filter does very little filtering, they are really only there to pick up bits in case of component failure or if when servicing someone is less than clean (a lot of mechanics from what I've observed)
Very few full flow oil filters filter down to reasonable levels and most European and Japanese OE filters tend to compromise more towards flow than filtration.

IMO real oil filtering only takes place with by-pass filtration, eg the centrifuge on a TD5.
The centrifuge on the TD5 can filter to the 1 micron level and below whereas most car full flow filters efficiency is usually in the range of beta2=18 to beta2=30 (18 to 30 micron nominal, eg. 50% of 30 micron particles in the relevant ISO multi-pass test)
The very best full flow filters efficiencies are down to beta2=6, but you pay through the nose for them and the range of vehicles they fit is often limited.

What is critical in dusty conditions is the air filter and its sealing.
Poor sealing or a poor air filter is obvious when oil testing, it shows quickly and savagely on contaminants and wear metals.
Install at least an OE quality filter element and make sure it's sealed correctly, a lot of aftermarket panel style filters often don't seal properly and never use something like a K&N or other cotton gauze style filters or oiled foam.
They are really poor at ultimate filtration, letting far too much dust through in the size ranges that do the most damage.

Where more frequent oil changes work in an engines favour is in cases of fuel dilution, which are becoming much more common with high pressure injection and short trips, in both DI petrol as well as diesel.
It really gives the oil a caning, most all oils don't cope, so if an owner isn't aware it's happening (most aren't) more frequent oil changes save massive long term wear.

I agree that most servicing schedules these days seem driven more by lessening waste (admirable) and keeping servicing costs down for the lease/fleet sector.

Thanks Guys,

I guessed that Ford would have extended the intervals to compete in the marketplace.
I intend to run the Terri for 4 years and then the wife will run it for 4 years so I'll certainly look at changing the oil more frequently.

I just have to make sure it's not obvious I've changed the oil because otherwise I'll probably invalidate the warranty !

I ran a Renault in the UK years ago and the oil filter was only changed every 2nd oil change, did about 220,000miles without any issues.
But I also remember bus companies changing filters regularly and only changing the oil every 100,000miles or so but they had the oil regularly tested. The testing warned them when the oil was breaking down but also indicated looming problems by checking on the quantity & type of metal particles in the oil.


Colin

Originally Posted by rick130

[snip] re-read post # 9, you don't have to change the oil frequently for good engine life

What is critical in dusty conditions is the air filter and its sealing.
Poor sealing or a poor air filter is obvious when oil testing, it shows quickly and savagely on contaminants and wear metals.
Install at least an OE quality filter element and make sure it's sealed correctly, a lot of aftermarket panel style filters often don't seal properly and never use something like a K&N or other cotton gauze style filters or oiled foam.
They are really poor at ultimate filtration, letting far too much dust through in the size ranges that do the most damage.

Where more frequent oil changes work in an engines favour is in cases of fuel dilution, which are becoming much more common with high pressure injection and short trips, in both DI petrol as well as diesel.
It really gives the oil a caning, most all oils don't cope, so if an owner isn't aware it's happening (most aren't) more frequent oil changes save massive long term wear.

I appreciated your post. Yes, I can say that at least right now, at 130,000 km, I have yet to add any oil between oil changes. The oil level does drop maybe a 1/2 litre in the 6,000 km between oil changes but nothing that gets me excited. At the same time, I can say that my previous Chev 5.7 litre (350 cu in), V8's rarely used any oil prior to say 250,000 km. I recognize however the Jag engine is so much more complicated, smaller, revs higher, and works harder than the 350 so that is why I am always watching.

Your comments re the K&N style filter and oil soaked foam got my interest. I recall my lawn mower air filter is oil soaked foam; maybe that is a hint.

I can believe that the engine intake air filter is what matters most. A failed filter can introduce fresh abrasives right into the cylinders on a virtually daily basis. I have often thought that of all the bush mods, the raised air intake is probably the best dollar value of them all. I do not know from which direction the LR factory one sucks air, but I have always thought that having the air scoop face to the rear made the most sense in desert driving conditions. Somehow ram air into a 4x4 does not seem like a priority.

I had never thought much about engine oil dilution, however with these direct injection type fuel systems being more common, yes, it would make sense that fuel, petrol or diesel, would more commonly make it if not past the rings, then the valves, and hence into the oil system.

My dealer recently showed me a cylinder head he was working on from someones LR. While I was impressed, I must say I would not look forward to seeing the parts from my engine that close up.

Changing oil at 5,000 intervals in a post 1990 Land Rover diesel engine is a waste of oil,nothing more,nothing less.People who claim longer engine life with more changes are living a fantasy,the cooling system servicing is far more important. Pat