Oops...regarding my previous message (below):

SAE 5W20, SAE 5W30 should read -20 - +10 degrees F (not -20 to -10)

AND the reference page is 17.8 for the oil grade chart, not "17." (Note
to self: proofreading works better BEFORE sending...)

I'd also like to add that the page says "Water-cooled from 1986" (i.e.
2.1 liter) in the footer, yet I suspect this designation applies only to
the oil cooler also shown on that page, as there is no oil viscosity
grade chart given anywhere for the 1.9 liter (83-1/2 - '85).

And lastly--please understand my first sentence in that message to mean
the Bentley doesn't offer info *specific* to grades of synthetic oils
(it was, after all, published in 1987)...which is to say yes, I assume
synthetic is available in these grades, no flame mail, pleeeeze...

Humbly self-corrected,
-George

Noto-Gaudette wrote:
>
> The Bentley manual does not offer info on synthetic oil weights. The oil
> viscosity chart on p. 17 is a bar graph; I've typed, below, the
> approximate outdoor temperature ranges in degrees specified for all the
> oil grades shown in the chart (in degrees, of course):
>
> SAE 40:                         +64 - +102 F (+20 - +40 C)
> SAE 30:                         +32 - +85  F (0 - +29 C)
> SAE 20/W20:                     +13 - +49 F (-10 - +9 C)
> SAE10W:                         -9 - +21 F (-22 - -4 C)
> SAE 20W-50 AND SAE 20W-40:      +12 - +83 F (-8 - +28 C)
> SAE 15W-50 AND SAE 15W-40:      +2 - +83 F (-10 - +28 C)
> SAE 10W-30                      -2 - +55 F (-21 - +14 C)
> SAE5W-20 AND SAE 5W-30:         -20 - -10 F (-28 - -9 C)
>
> No info available for other grades. I notice that their doesn't seem to
> be a single oil recommendation that covers New England's three
> seasons--or even just Summer; from May through September we experience
> temps ranging from "frost" to 100+ F (today, 70's). Even July dips to 60
> F now and then, from June to Sept. temps well above 85 F are
> commonplace. Thoughts?
>
> George
> 83-1/2 Westie