I meant ive ran millers for 8000 miles not the same oil

So... are u saying i should change the brand of the oil i use or just the spec (for both cars?)

Cheers [/quote]

Sorry, misunderstood you lol. There is nothing wrong with the brand of oil as far as I know. However, I would recommend you change the grade of the oil you are using. Especially if you like to use your car as it was designed I would think something which goes up to 50. The oil you are using will be struggling at the temps you are putting it under and will not be lubricating sufficiently. I would go for 10W 50!"