Conventional in bmw n54 for 60k kms

Joined
Feb 22, 2025
Messages
9
I've been using conventional 10w40 castrol gtx and a litre of motomaster 5w20 for the past 60k kms since I had the car, I didn't know I needed synthetic.

The car is running fine it is stock and not driven hard.

Have I done damage?
 
Welcome.

It would be very helpful if you'd tell us what the application is ... what car, engine, year, etc. You don't drive it hard; OK. But also what's the environment in your area; where are you located?

It's unlikely you've done damage, but without understanding what you're putting the lube into, and your locale, it's pretty much a wide-open range of guesses.
 
Welcome.

It would be very helpful if you'd tell us what the application is ... what car, engine, year, etc.

It's unlikely you've done damage, but without understanding what you're putting the lube into, it's pretty much a wide-open range of guesses.
Hi, the engine is stated in the title of the post.

2007 bmw 335i 198,000kms
 
Welcome.

It would be very helpful if you'd tell us what the application is ... what car, engine, year, etc. You don't drive it hard; OK. But also what's the environment in your area; where are you located?

It's unlikely you've done damage, but without understanding what you're putting the lube into, and your locale, it's pretty much a wide-open range of guesses.
Canada British Columbia. I'm in underground parking
 
I'll delete the post I'm just curious because everywhere says to use synthetic now that I'm researching it, yet I'm on original turbos running a conventional with no issues so idk
 
There's no way any of us can tell you realistically what condition your engine and turbo is in after running conventional oil for 60k kms. It could be completely fine, it could be a disaster, or somewhere in between. It would take some disassembly and inspection to know for sure. Having said all that, if I were you, going forward I'd find out what BMW oil spec your engine calls for and use an oil that meets that.
 
There's no way any of us can tell you realistically what condition your engine and turbo is in after running conventional oil for 60k kms. It could be completely fine, it could be a disaster, or somewhere in between. It would take some disassembly and inspection to know for sure. Having said all that, if I were you, going forward I'd find out what BMW oil spec your engine calls for and use an oil that meets that.
Well that's the whole the point of the post, it calls for full synthetic.
 
10w40 GTX api sp is fine, but forget adding the litre of 5w30.
I’m using the same oil in my daughter’s 2022 3.6L Acadia and it hasn’t blown up yet.
If it was mine I’d use 0w40 Delvac instead and go further between oil changes.
 
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Those wouldn't lubricate well, especially a twin turbo high heat set up.
My point is sarcastic. You have gone far off the manufacturer recommendations. And not just with a slightly thinner or thicker oil. You have not shared your motivations or theories with us. There are some instances, I suppose, that folks might choose conventional over synthetic, but this ain’t one. I am almost inclined to view this thread as a troll
 
How long have the oil change intervals been?
14,000! Changed a full 1000 miles early! (just joking)

Even 5000 mile OCI's on conventional can cause some engines to develop plenty of varnish and sludge. Including carbon on the piston rings. While the wear rate might be low, modern engines have other, expensive, ways to show owners just how well they are doing on maintenance.
 
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