The Macan uses Alusil cylinder lining and there are cases of bore scoring. While it's not an epidemic, I am wondering if there is a better oil than the current Edge 0w40 that I'm using to protect from this happening?
Best oil for Alusil cylinder lining?
- Thread starter tcp71
- Start date
You could try 5w40 with Porsche A40 approval, shorten your OCI to 5k miles, insure correctly sized engine air filters, drive conservatively until the engine is warmed up. However being in Canada an 0w40 is probably best overall.
There's a good YT video out there about this problem with older 911's. I think the solution was DLC piston skirts but I don't remember.
BMW has been using Alusil blocks w/out cylinder sleeves for decades. The blocks are an alloy of Al/Si and when honing the cylinders they use a process to remove aluminum leaving the much harder silicon behind. Usually the Alpina tuned BMW V12/V8 engines had this problem on one or more cylinders.
FWIW Alusil isn’t a lining, it’s an alloy. Unlike Nikasil which is a coating.
My BMW had an Alusil block, which was a replacement from the previous Nikasil. I am mystified with those reports of scoring since Alusil is extremely durable and hard. There must be some other factor at play or the block was not properly etched and honed at the factory. Nevertheless no oil is going to correct that, I agree with either A40 or BMW Longlife-01 approval. But if there is something wrong it’s not going to prevent failure. The Driven oil isn’t magic.
My BMW had an Alusil block, which was a replacement from the previous Nikasil. I am mystified with those reports of scoring since Alusil is extremely durable and hard. There must be some other factor at play or the block was not properly etched and honed at the factory. Nevertheless no oil is going to correct that, I agree with either A40 or BMW Longlife-01 approval. But if there is something wrong it’s not going to prevent failure. The Driven oil isn’t magic.
Isn't Alusil what was used in the Chevy Vega? Those were a mechanical disaster on wheels!
Not Alusil but a similar alloy called A380. However the well-known problems with the Vega engine were not related to the alloy. GM had difficulty during development of the 2300 when they were working out the etching and honing of the blocks, but that was resolved prior to the first production vehicle. That alloy was one of the best parts of the engine.
The major problem with the production Vega engine was inadequate cooling which resulted in warping and coolant leaks.
Why would 5W-40 be better than Castrol Edge 0W-40 that is currently used?
I do all those things and don't actually expect a problem. Edge 0w40 has A40 approval. Just wondering if there were any magic unicorn tears known to help.
Usually a marginally higher HTHS however I did say that a 0w40 was probably best for the Canadian climate.
It's natural to look for an oil which could prevent the issue from occurring because as the owner of the vehicle that's really the only thing you really have control over other than spending $$ for a rebuild or whatever shops do to "fix" the issue.
I have a tendency to waaaay overthink every little thing. I suspect < 1% of these engines will have this issue, but it sits in my mind and I thought there may be a known juice to handle it.
Edge 0W-40 is a very good engine oil, so I think the best you can do now is enjoy driving the Macan
The article you linked has all of the right suggestions, but these apply to any motor. Change your oil regularly with a quality product. Use good filters to reduce debris-caused scoring. Don't let the car run rich and increase cylinder wall washdown. Keep your injectors clean.
In theory higher hths and zddp may reduce this but is it worth spending $18/qt on the brand they conveniently sell? Up to you.
Yes it was. Reynolds called it A390 but it was also known as alusil. I remember these engines well, they had more cylinder scuffing than possibly any engine ever built. Ford parts rebuilders actually remaned these blocks and used a sleeve in the bores and were sold to Chevy dealers, the engine was much more reliable with no scuffing of the cylinders. The cost of a short block with liners in 1975 from them was $165 (dealer price), I know. Cracks in the head and bad radiators were also common, FPR also did heads for these a bare head was $25 or a ten spot at the back door if you were in the know. LOL
https://en.wikipedia.org/wiki/Alusil
Alusil seems to score in high performance applications. BMW S65 and S85 are seeing a lot of it now that they aren't blowing up due to rod bearing failure as often. Perhaps it is secondary to failure of the piston skirt coating. I observe that the Germans have moved away from it as the final bore finish and went to arc sprayed / plasma deposited "liners".
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M1 ESP X4 is probably a better oil than the Edge 0W-40. If you're running full SAPS you can try PP Euro 5W-40. About the same HTHS as the ESP X4 though (3.8). Ravenol VST and Motul Xcess or Xclean Gen2 are slightly higher HTHS options also vs the Edge.
I suspect there is no oil that will prevent this.
And topping it with a cast iron head.
That head assembly was HEAVY. I remember removing one to change a blown head gasket. And the weird part was the gasket was leaking coolant to the outside, not cylinder pressure into the coolant. That engine was GM's first "corporate" rather than divisional design and it was a mess. About a year before production they "threw it over the wall" to Chevrolet where it was treated like a turd in a swimming pool.
Also keep in mind that clean fuel injectors make fuel into fine mist that burns well. Dirty fuel injectors make big drops of fuel that don't burn well, and allow some fuel to get past the pistons and into the oil, and fuel in oil reduces how well the oil protects the engine.
Bottom line, clean fuel injectors are important for making oil protect the engine. So regular use of a fuel system cleaner with PEA helps the oil work well.
Bottom line, clean fuel injectors are important for making oil protect the engine. So regular use of a fuel system cleaner with PEA helps the oil work well.
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Amazing all these pretty much $30K and up, throw away german car engines with Al bores. Perfect engineering to sell either engines or cars.
DT40 by Driven if you want to believe LSJR.
They recommend a few more in the vid if I recall correctly.
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