Volvo 15w50 or Valv all-fleet 15w40?

[lars11]

I know about the Volvo recommendation but now there are huge sales on both the valvoline all fleet and mobil 15w40.
How big a difference would it be to use a mineral 15w40 instead of the volvo 15w50 API SG mineral?
Will I damage the engine? The all-fleet looks quite sturdy on the label, but it is obviously a bit thinner when hot.
what do you think?

 

[CMB]

I think you will be fine with the 40wt.

 

[PT1]

I would stick with the manufacturers specs