How often do you change oil

[kerry]

My 99FG has 6k miles on a Shell rotella dynthetic oil change. My Lubrichek shows oil is 2 out of 1. With 10 meaning it needs to be changed

 

[kerry]

My 6.5 GMC diesel shows 8 after 5k miles

 

[gait]

every so often .... a mixture of 5,000 km, when its convenient, and when it looks like it needs it.

I don't have a lubricheck. I guess I'd look for charts of viscosity and other characteristics of the oil on their scale. If water and anti-freeze (they show in their video) is rising then there is a problem with the engine that is showing in the oil. I want to know about the fundamentals of the oil.

If I bought one I'd start by testing every 1,000km and every couple of months to see what the trend is. And add my observations of the oil.

 

[PKDreamers]

Hi,
FG 649 2003 Every 6 months because we dont use it enough.
Or when we travel before and after trips.

 

[kerry]

I was very surprised at the difference in the quality of oil at roughly the same mileage between my GMC and Fuso.

 

[westyss]

I go 10,000 km's between changes with synthetic, normally.....I have gone more than that and it seemed the oil was pretty good after that, not checked by a lab or anything just from looks, feel. The Western Star dealer says 10,ooo km's, so 6,000 miles seems appropriate yet you show the oil as still being good for longer so it should go longer, thats why I use synthetic so I dont need to change oil while on our Mexico trips.
Good question too! I would like some thoughts on this too.

 

[kerry]

A Lubricheck is apparently as accurate as more expensive oil testing equipment: https://www.thetruckersreport.com/truckingindustryforum/threads/oil-tester.276435/

 

[westyss]

A Lubricheck is apparently as accurate as more expensive oil testing equipment: https://www.thetruckersreport.com/truckingindustryforum/threads/oil-tester.276435/

Thanks for the link, I bought one, seemed like the right thing to do for me, saves the guesswork about the oil condition while on a trip.

Why do you think the Fuso rating on the oil is so different than your GMC's rating?

 

[kerry]

I'm not sure. Better filtering system? More oil per cubic liter of engine? Better tolerances in the Fuso? I was towing 7000lbs in 100 degree weather with the GMC for a good portion of those 5k miles so perhaps hard use?

 

[JohnRogers]

Blow by is number one cause of dirty oil and some engines just are dirtier than others an old perkins in my woodchipper can do 500 hrs an look like brand new and the oil in my old Hilux was black the second it hit the sump, the dirtier the exhaust output usually the dirtier the oil

 

[unkamonkey]

I can run my Volvo for a few miles over the change interval and it is sort of discolored. My neighbors diesel tractor just after you start it up, the oil is black. I generally change the oil in the Mitsu about every 5,000 miles. the book says I can go longer.

 

[charlieaarons]

My last oil change was at 25600mi (700hrs) and analysis showed 44ppm Fe, 0 Pb, 4 Al , 1 Cr, 0.4% soot, TBN 11.5. I use Delvac 1 SHC. Mercedes recommends 1200 hrs (45000mi in my usage). It takes 29L and has a centrifuge.

Charlie

 

[kerry]

Blow by is number one cause of dirty oil and some engines just are dirtier than others an old perkins in my woodchipper can do 500 hrs an look like brand new and the oil in my old Hilux was black the second it hit the sump, the dirtier the exhaust output usually the dirtier the oil

My GMC has 20k miles on a brand new engine. Don't know how many miles on the Fuso because the engine was replaced before I bought it. At least 45k

 

[yabanja]

Dirt use

Because my FG is driven primarily at low speeds in the dirt I change mine every 5000 miles.

Allan

 

[pugslyyy]

I change every 5k (miles) on mine, which meant I did 3 oil changes on the road this summer.