Workshops with engine oil flushing machine

[Powersteer]

We have all seen workshops with ATF flushing machines where they can try to change out all the used ATF fluids.

I have a car with very long oil cooler lines, if I do a normal drain and fill, I would only be changing 4.3L out of 7.8L in the system as another 3.5L would still be left in the oil cooler lines.

Do you know any workshops that uses a machine to flush out the engine oil similar to what they do with ATF? I would imagine a properly designed adaptor on the oil filter should work.

[kobayashiGT]

On 7/29/2025 at 9:50 AM, Powersteer said:

We have all seen workshops with ATF flushing machines where they can try to change out all the used ATF fluids.

I have a car with very long oil cooler lines, if I do a normal drain and fill, I would only be changing 4.3L out of 7.8L in the system as another 3.5L would still be left in the oil cooler lines.

Do you know any workshops that uses a machine to flush out the engine oil similar to what they do with ATF? I would imagine a properly designed adaptor on the oil filter should work.

Hmmm. i would imagine that the workshop will pour in new ATF oil, run the engine for awhile and then flush again. might do it a few times to purge out all the oil. 

[Gnahp]

I did a quick calculations 😁

if you change the engine oil 3 times in succession,  you will reduce the old oil ratio to 9%

if you change 6 times in succession,  that will bring down the old oil ratio to 0.8%

[Powersteer]

On 7/29/2025 at 10:40 AM, Gnahp said:

I did a quick calculations 😁

if you change the engine oil 3 times in succession,  you will reduce the old oil ratio to 9%

if you change 6 times in succession,  that will bring down the old oil ratio to 0.8%

@Gnahp Haha I've thought of that too, that would be quite wasteful and not great for the environment 😄

[Beregond]

On 7/29/2025 at 12:14 PM, Powersteer said:

@Gnahp Haha I've thought of that too, that would be quite wasteful and not great for the environment 😄

I saw some Ower do it with semi syn oil.

Drain out. And fully filled with cheap semi syn. Run for 20 min and drain again.

My bro dun use expensive oil. Instead he change at every 5-6k instead.

[Gnahp]

On 7/29/2025 at 12:14 PM, Powersteer said:

@Gnahp Haha I've thought of that too, that would be quite wasteful and not great for the environment 😄

your drain volume is 4.3L

3 times is 12.9L

only 5L more than complete oil change at 7.8L when you do the 3 times thing 😁

engine oil flushing (if there is such thing) also use new oil to flush out the old one, have wastage too

[kobayashiGT]

On 7/29/2025 at 10:40 AM, Gnahp said:

I did a quick calculations 😁

if you change the engine oil 3 times in succession,  you will reduce the old oil ratio to 9%

if you change 6 times in succession,  that will bring down the old oil ratio to 0.8%

who you ask. ChatGPT ah? 

My theory is that the old oil is good for the car also lah. hahaha. is like you go duck rice stall, the gravy they will mix with all the old supplies one mah.  😁

[Powersteer]

On 7/29/2025 at 1:59 PM, kobayashiGT said:

who you ask. ChatGPT ah? 

My theory is that the old oil is good for the car also lah. hahaha. is like you go duck rice stall, the gravy they will mix with all the old supplies one mah.  😁

Hahhaha 

This I agree is nicer, like prawn noodle soup mixed with old stock

[Gnahp]

On 7/29/2025 at 1:59 PM, kobayashiGT said:

who you ask. ChatGPT ah? 

My theory is that the old oil is good for the car also lah. hahaha. is like you go duck rice stall, the gravy they will mix with all the old supplies one mah.  😁

my rusty primary school maths lah

I don't mind (up to 10%) residual old oil during oil change, but TS case is excessive 

if that was my car, I will do the classic drain and fill oil change but halve the interval

 

 

[Gnahp]

the duck rice gravy reminded me of certain angmo chia

manufacturer says topping 1L  engine oil every 1,000km is normal and within specifications 

and their oil change interval is 15,000km

by right no need to change oil forever, at 15,000km, you already pour total 14L of fresh oil into the engine 

just keep on topping up every 1,000km 😁

 

[Jamesc]

No need to flush. 

Transmission oil is not like engine oil with combustion. 

Might have more problems if you flush it.

[Jamesc]

Smart people always flush toilets and never flush engines or transmissions.

[Powersteer]

On 7/29/2025 at 3:18 PM, Gnahp said:

the duck rice gravy reminded me of certain angmo chia

manufacturer says topping 1L  engine oil every 1,000km is normal and within specifications 

and their oil change interval is 15,000km

by right no need to change oil forever, at 15,000km, you already pour total 14L of fresh oil into the engine 

just keep on topping up every 1,000km 😁

 

 

Sounds like a 2 stroke engine, very green indeed! 😆

[Mkl22]

On 7/29/2025 at 12:14 PM, Powersteer said:

@Gnahp Haha I've thought of that too, that would be quite wasteful and not great for the environment 😄

Just change more often. The shop with the machine will also need to recover the cost of the machine. Maybe charge you an extra $60? Might as well put that money to shorter oil change intervals. 

[Mkl22]

On 7/29/2025 at 3:18 PM, Gnahp said:

the duck rice gravy reminded me of certain angmo chia

manufacturer says topping 1L  engine oil every 1,000km is normal and within specifications 

and their oil change interval is 15,000km

by right no need to change oil forever, at 15,000km, you already pour total 14L of fresh oil into the engine 

just keep on topping up every 1,000km 😁

 

15000km is nothing. The British trash ingenium engine better yet. 21000km for the diesel engine! Hahaha. Watch YouTube… so many kaboom!!  
 

[Gnahp]

On 7/29/2025 at 7:45 PM, Mkl22 said:

15000km is nothing. The British trash ingenium engine better yet. 21000km for the diesel engine! Hahaha. Watch YouTube… so many kaboom!!  
 

not one-upping you

but my wife's car official oil change interval is 25,000km

I dare not follow 

that car I change oil 3 times a year, about every 12k km ~ 13k km 

[Mkl22]

On 7/29/2025 at 9:13 PM, Gnahp said:

not one-upping you

but my wife's car official oil change interval is 25,000km

I dare not follow 

that car I change oil 3 times a year, about every 12k km ~ 13k km 

Sorry typo. 21k miles or 33600km. 🤣
 

crazy to go above 15k. That’s the max I’ll go and must be approved oil on MB list. But then why so much hassle. Just 10k and very safe. 25k is pure madness. Even with 10year engine warranty so what. Anytime can say some components not covered or labour not covered and then need to argue one’s case. 

Edited July 29, 2025 by Mkl22

[ER-3682]

On 7/29/2025 at 4:39 PM, Jamesc said:

No need to flush. 

Transmission oil is not like engine oil with combustion. 

Might have more problems if you flush it.

Agreed,esp Older Gearbox..