[Erik]

Anyone have experience with Sunoco Super Dynalube 20W-50 or 15W-50. I’ve been using Duckhams Q 20W-50 for the last 2 years, but it’s discontinued in Denmark.

I could always change to Castrol GLX 20W-50, but the Sunoco oil is a great deal cheaper. The Castrol GTX 15W-40 is an API SL/CF; the other oils are API SF/CF. It seems to me that the engine is more pone to leak the SL oils.

My motor is a Spider 1750 ’70.

Erik

 

[alfabeach]

Here in the states with the Castrol GTX, you can get a "high mileage" version. It has additives to condition the seals. It has stopped most of my leaks.

 

[Erik]

After 2 sesons with Duckhams it has no leaks, had on GTX 15W-40 and Valvoline Max (high mileage) 10W-40, which also have additives refreshing seals. But it can be down to not been driven for 3 or so years. Engine have a rebuild 14000 miles and 9 years ago.
However, since no one have anything, good or bad, to say about Sunoco oils, I'll go for GTX 20W-50.
Erik