synthetic oil???

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Thu 30 Sep 2004 19:56
synthetic oil??? - notlob
I've been using synthetic oil in my Mercedes 280 SL(1985- type 107)for about 4 years now.Yesterday I took the car in for an oil service at the same small independent garage.Upon collecting my car and paying I saw that instead of 10w-40 grade I got 5w-30 grade.When I said that the grade was too low, I was told that all high performance cars use this grade and was assured that it would not harm the engine.Is this correct or am I being fobbed off? The car has done 90k miles and I average 2K miles annually.

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Thu 30 Sep 2004 20:59
synthetic oil??? - John S
No, not all high performance cars use this grade, especially the older ones. Don't worry about the 5W (cold viscosity) but check what the manual recommends for your car, and make sure the second number (hot viscosity) is met.

JS
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Fri 1 Oct 2004 09:04
synthetic oil??? - Roger Jones
Interesting that you use fully synthetic in a car of this vintage. I trust that there are no leaks and that you have experienced no other problems. Many advise against its use in classics such as yours, but if it works for you, then fine. How often do you change it?

As John S says, check the manual.
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Fri 1 Oct 2004 11:09
synthetic oil??? - arky
It is unlikely a car of this vintage can use 5-30w oil. These cars were designed when 20-50w or 15-40w were the norm (although I recall some economy (low performance) Ford models used a 10-30W oil but only in the summer.

My 1985 Passat was killed by use of said Ford 10-30W oil instead of the correct 15-40W. Blue smoke appeared after about 3000 miles....

Stick to the manual recommendation...
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