I dont use it because my mates use it, i use it because i was told to use it by my engine builder. A lot of people have taken advice from the people who build and set up their cars.

'Have you all gone completely mad or are you on a deathwish for your engine? If MadRod can use Silkolene PRO S 5w-40 or 10w-50 so can you!'

No thanks.
Can i pick your brains then please? what is 0w-40 like then? Is it totally unsuitable? castrol rs.

 

It's a pao based oil (proper synthetic) so it is a good one.

It's not totally unsuitable but some older high mileage engines sound more tappety on it than a thicker oil which will mask the noises.

It will flow better and lubricate better from cold which keeps engine wear down.

Cheers
Simon

 

No its not totally unsuitable, just not needed.

When hot a 0w-40 and a 5w-40 are both the same viscosity, the only difference is when cold and the 0w is slightly thinner at very cold temps.

It is also used for fuel economy oils by the likes of the vag group.

Cheers

Simon.

 

When i bought my car it used castrol rs 0w-40 and it tapped like a bastard when hot or cold, i put 10w-60 in it and it made it better, not brilliant but better. I had the engine rebuilt and now use 10w-60. I put the damage on the engine down to the 0w-40, would this be possible? It didnt do many miles at all with this oil in it. The guy who owned the car used this oil cos it was expensive so he could brag about how much he spent on his car and some guy who was into rallying told him to use it.

 

The 10w-60 will mask the noises that are there, it's inevitable as it's a thick as some sae 90 gear oils.

You're likely to do more damage from a wear perspective by using an sae 60 as there is mor viscous drag, friction heat and wear.

cheers
Simon