Why You Should Use 10W40 Semi Synthetic in a VVC

[tangomikeromeo]

With nothing but the anecdotal to offer:

I had a VVC160 that was well used (45,000 miles) before me that I then ran on comma fully synthetic 5W50 for a few years and close on 10,000 miles. By that time there was too much play for DVA to be comfortable with it and it sounded like a mouse was in there with a .50 calibre machine gun under load. No idea what oil it ran on before my tenure.

Whether it was miles or oils that did for the wear but wear it did. 

Now DVA VVC free. 

[Mechanical Moz]

Did you ever try the 5w50?  I'm trying to decide which way to go with the next oil change. 

I ran the Comma 5w50 in my old EU2 VVC but went to 10w40 semi synthetic on my rebuilt EU3 VVC.  The oil pressure drop off when used on track days seemed higher though so I went back to the 5w50.  I'm pondering if a 10w40 fully synth would be better under the demands of track use.  Or maybe a 5w40?  It should be the same viscosity once warm and there is a much broader choice of oils in that grade.

[john milner]

10w40 full synthetic might be hard to find and expensive. My casual investigations into this a couple of years ago found nothing at a sensible price.

[revilla]

I'm afraid I didn't get around to investigating it properly. What I do know is the one time I tried a fully synthetic oil the VVC mechanisms were significantly noisier and didn't sound like they were particularly enjoying it. They were a lot quieter when I switched back again.