Why I run synthetic in our waterboxer:

https://www.youtube.com/watch?v=yX7RTLn_QCE

https://www.youtube.com/watch?v=MVn5OzuHtjg

Yes, I rarely start the Vanagon in the winter - once a month on warm days to keep it turned over (no roadsalt on our camper!) - but faster flow at cooler temperatures, even 5C/40F in the spring and fall is what I'm after, as I want to keep this engine!   Most engine wear occurs in the 60 seconds after a cold start, after all.

Plus, synthetic resists heat breakdown better, and good knows our waterboxers run hot at times.

Also, Frank Condelli recommends it, and given how many kms are on his personal Vanagon....

The rest of the family fleet was changed to synthetic to save money - 10000 km drain intervals, instead of 5000 km, but after a cold start incident without a block heater (the block heater cable had broken in the -39C/-39F cold),  when others in the parking lot couldn't start, it's synthetic all the way for me!

James

> Date: Thu, 13 Aug 2015 19:39:25 +0000
> From: jim.felder@GMAIL.COM
> Subject: Re: Flickering oil light on idle.
> To: vanagon@GERRY.VANAGON.COM
> 
> You will probably be OK when you run the 20W50. I don't think I would run
> synthetic in a water boxer (covers head awaiting hail of greek fire, stones
> and arrows). Just Castrol or other good petroleum. The most mileage people
> have ever gotten out of them that I can recall have run petro. In any
> event, just put the correct weight in and then see if you should start
> saving. The money you save not buying synthetic should do it.
> 
> Jim
>