There is a theory which floats around on the internet that thinner oil circulates better around the engine during startup preventing wear but I found this theory.to be false. Ive been running 5W40 in 5W20 and 5W30 engines lately and oil testing shows less iron&copper meaning better wear.
Some companies like Amsoil and Redline will engineer a buttkicking 5W30 but the fact is any 5W40 you can find at Walmart is just as good if not better than a topline 5W30. So a cheaply made Group III 5W40 is just as good as any 5W30 produced by Amsoil or Redline.
If your engine calls for 0W20 or 5W20 I wouldnt be afraid to go thicker like to a 5W30. I believe the difference is felt over 100000 miles.
If you push your engine like towing or livery work or Subaru turbo aftermarket mods than no doubt 5W40 is the only oil to consider.
In terms of HDEO vs Euro 5W40 I find that HDEO is generally thicker but both are thicker than 5W30. In terms of Amsoil/Redline Group IV/V vs cheaper made Group IiI 5W40s I think you can make it on the cheaper made varieties.
The cheap 5W40s Ive found are:
AmazonBasics Euro and HDEO (WarrennDistributing/Mag1/Supertech) API SN
Chevron Delo API SN Plus
Mobil Delvac 1 API SN
Castrol API SN
Mobil 1 Turbo Diesel Truck API SN
Not included in the list is Shell Rotella T6 because lacks an API gas engine rating.
All of these will be better than any 0w20, 5W20 or 5W30 out there. As for cold starting you will know when you need the better starting oils like 0W like if you live in Alaska, but I dont live in cold places where thats a concern...
Some companies like Amsoil and Redline will engineer a buttkicking 5W30 but the fact is any 5W40 you can find at Walmart is just as good if not better than a topline 5W30. So a cheaply made Group III 5W40 is just as good as any 5W30 produced by Amsoil or Redline.
If your engine calls for 0W20 or 5W20 I wouldnt be afraid to go thicker like to a 5W30. I believe the difference is felt over 100000 miles.
If you push your engine like towing or livery work or Subaru turbo aftermarket mods than no doubt 5W40 is the only oil to consider.
In terms of HDEO vs Euro 5W40 I find that HDEO is generally thicker but both are thicker than 5W30. In terms of Amsoil/Redline Group IV/V vs cheaper made Group IiI 5W40s I think you can make it on the cheaper made varieties.
The cheap 5W40s Ive found are:
AmazonBasics Euro and HDEO (WarrennDistributing/Mag1/Supertech) API SN
Chevron Delo API SN Plus
Mobil Delvac 1 API SN
Castrol API SN
Mobil 1 Turbo Diesel Truck API SN
Not included in the list is Shell Rotella T6 because lacks an API gas engine rating.
All of these will be better than any 0w20, 5W20 or 5W30 out there. As for cold starting you will know when you need the better starting oils like 0W like if you live in Alaska, but I dont live in cold places where thats a concern...
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