Oil Change Intervals

**wbute** · 06-09-2017, 11:20 PM

What does everyone do regarding oil changes these days? I always changed the oil in my WB every 5000km with a new filter. My current Hilux and Mrs Prado, I do it every 10000km (diesel) but really it comes out bloody black looking. If you follow Berrima Diesel they give the manufacturers recommended oil a bad rap. Apparently the super thin oil makes huge blow-by which causes all sorts of inlet manifold sludge build up.
I wonder if the long oil change intervals these days is just to sell cars. They only expect them to last a few years it seems.

**Valencia** · 06-09-2017, 11:39 PM

My 2004 Mazda Bravo 4x4 turbo diesel it gets changed every 5000 km overkill maybe but i had the rocker cover gasket done last service due to small leak my mechanic took pictures of my head it was clean as a whistle
i have used the same oil from day one
198000 km trouble free so far

My SS ute every 10000km

**axistr** · 07-09-2017, 05:07 PM

I change my mineral base oils every 5,000km and where synthetic oil is used every 7,500km, basically half of what the manufacturer recommends, probably a bit of an overkill. I use Shell Rimular X in most of my vehicles. Its a diesel engine oil but I still use it in my petrol and diesel engines and have done so for the last thirty years.

Some people will tell you that diesel oil will wash out old petrol engines and use more oil. Old wise tale that isn't necessarily correct. Diesel oil has more detergent in the oil to stop sludge build-up. Due to diesel engines having higher compression ratio, more soot will naturally pass by the rings. All engines will use oil new or used, but its the carbon, fuel and soot that passes over time into the oil that raises the level and minus the oil usage that keeps the oil at a constant level on the dip stick. Oil never wears out its the contaminants from the combustion process that slowly adds to the oil and when there is more contaminants floating around than the original oil the contaminants leach out and sludge forms on internal parts, building up and can't be drained out during an oil change. Much worse and earlier when using a real bad cheap manufactured oils. I never used cheap oils.

I found the opposite In just about all cases, when I switched customers vehicles that had been using oil to Shell Rimular it dramatically reduced the oil burn after around 3,000km. It cleaned out and freed up rings that were previously gummed up in the piston ring lands not allowing the rigs to seal in the bore.

Most diesel engine oils have Zink added to the oil during manufacture to better help lubricate camshafts and lifters which is also a bonus for standard or performance petrol engines, especially Holden V8 engines which have had cam issues over the years. I use full synthetic oils in my beamer and Ranger only because the manufacturers state they must be used or warranty is void. I use Shell helix ultra (full synthetic) for these vehicles. Quality full synthetic oil do have a lot of detergent in them and suspend contaminants for longer and will have longer oil life intervals. Most later model cars now come with larger capacity oil sumps, the more oil the longer it takes for the oil to contamination ratio to reach its limit. Its for this reason large diesel trucks commonly come with 50lt sumps and 25-35,000 km oil change intervals.

Hope this helps some of the myths about oil changes.

**jason.ruff** · 07-09-2017, 07:13 PM

I completely agree. We run 2 tugboats with 3 x V12 Caterpillar engines, one vessel has centrifuges and one doesn't. 600 Litre sumps so high volume of oil, but we get twice as long for servicing on the engines with spinners because we remove the carbon and crap. Ours is all sample based oil changes with samples taken every 250Hrs, so we can closely monitor oil condition. We change the oil every 12 months unless required to prior.

**Valencia** · 07-09-2017, 07:37 PM

Originally Posted by axistr

I change my mineral base oils every 5,000km and where synthetic oil is used every 7,500km, basically half of what the manufacturer recommends, probably a bit of an overkill. I use Shell Rimular X in most of my vehicles. Its a diesel engine oil but I still use it in my petrol and diesel engines and have done so for the last thirty years.

Some people will tell you that diesel oil will wash out old petrol engines and use more oil. Old wise tale that isn't necessarily correct. Diesel oil has more detergent in the oil to stop sludge build-up. Due to diesel engines having higher compression ratio, more soot will naturally pass by the rings. All engines will use oil new or used, but its the carbon, fuel and soot that passes over time into the oil that raises the level and minus the oil usage that keeps the oil at a constant level on the dip stick. Oil never wears out its the contaminants from the combustion process that slowly adds to the oil and when there is more contaminants floating around than the original oil the contaminants leach out and sludge forms on internal parts, building up and can't be drained out during an oil change. Much worse and earlier when using a real bad cheap manufactured oils. I never used cheap oils.

I found the opposite In just about all cases, when I switched customers vehicles that had been using oil to Shell Rimular it dramatically reduced the oil burn after around 3,000km. It cleaned out and freed up rings that were previously gummed up in the piston ring lands not allowing the rigs to seal in the bore.

Most diesel engine oils have Zink added to the oil during manufacture to better help lubricate camshafts and lifters which is also a bonus for standard or performance petrol engines, especially Holden V8 engines which have had cam issues over the years. I use full synthetic oils in my beamer and Ranger only because the manufacturers state they must be used or warranty is void. I use Shell helix ultra (full synthetic) for these vehicles. Quality full synthetic oil do have a lot of detergent in them and suspend contaminants for longer and will have longer oil life intervals. Most later model cars now come with larger capacity oil sumps, the more oil the longer it takes for the oil to contamination ratio to reach its limit. Its for this reason large diesel trucks commonly come with 50lt sumps and 25-35,000 km oil change intervals.

Hope this helps some of the myths about oil changes.

Rimular X is what i have been using in my Bravo to Lenny

**wbute** · 07-09-2017, 07:51 PM

No short running is important. Any engine that stays hot like heavy vehicles or taxis get massive hours up.

**Beachy** · 07-09-2017, 10:13 PM

I have always ran John Deere diesel oil which is made by Fuchs oil for years
Nissan patrol 450000 Klm
80 series cruiser 525000 klm
200 series cruiser 300000 klm
79 series cruiser 200000 klm
No moter issues with any oil changed between 12 and 15000 klm

**gregbark** · 08-09-2017, 10:31 AM

There is an old saying "You get what you pay for" and buying cheap oils is not economical in the long run. With the technical knowledge and the variety of Manufacturers these days it is possible to get the best. That refers to both product information and the oil to suit your needs. Companies like Fuchs, Penrite and others can all advise, along with forum site information, such as here.

**Camper** · 08-09-2017, 02:55 PM

Originally Posted by axistr

Hope this helps some of the myths about oil changes.

Thank you for this explanation, as someone who has changed/cleaned/serviced many a deep fryer - including filtering dirty oil through coral substrate to reuse - this made a lot of sense to me.

The oil is a matrix suspending impurities and carrying heat.