Hi Guys,

My local Mitsu dealer says they use Caltex Havoline 15W-40 in my 380. It needs a top up so just wondering what your experience is with this oil. As I want to avoid mixing oils.
I thought Mitsu uses Penrite....?

Why so thick???

try this link.
dont read past page 3
http://www.aussiemagna.com/forums/showthread.php?t=84958&page=2&highlight=oils

Why so thick???

By "thick" are you referring to the 15W?

try this link.
dont read past page 3
http://www.aussiemagna.com/forums/showthread.php?t=84958&page=2&highlight=oils

Ooops! I read past page 3! lol
Seriously - I opened up a 6G72 12 valve engine at 240,000 km because it had a burnt exhaust valve. The bores were perfect, no wear ridge at the top, no scoring, just perfect. Oil and metal technology have come a long way since the days when any car approaching 100,000 miles would be dirt cheap because the engine would be worn out.
Since then I have stopped worrying about the relative merits of different engine oils - the engine will outlive the rest of the car in this instance. So it comes down to personal preference really.(IMHO) Can't go wrong with any of the oils mentioned in the link, but Penrite oils seem to be popular on this forum.

By "thick" are you referring to the 15W?

Yup 5-10w is actual recommend

Most dealers actually use 5w-30

Think I'll just top up with what Mitsu used before at least until the next service.

Why so thick???

There are so many misconceptions about oil weight, particular the weight of oil at 'room' temperature. It is important to take notice of the latter number '40', the viscosity at operating temperature. The difference between a 10 and a 15 weight at room temperature is not as large as you think. The main difference being the slightly longer time it will take the oil to reach operating temperature and optimum viscosity. Both the 10 and 15 room temperature viscosity rating are too thick to lubricate an engine efficiently. There will be similar 'wear' between both.

I agree that there is little point going from a 5W-30 weight synthetic oil to a 15W-40. There doesn't appear to be any logical reason for doing this, except deliberately straying outside of manufacturer recommendations. If the engine has high K's, it might be necessary to move up to a 5w-40.

Dave i am running 5-60w. would that be why my car takes a while to warm up?

Just use Penrite HPR10 or Syn 5 and stop fretting. lol

Dave i am running 5-60w. would that be why my car takes a while to warm up?

Not quite. The '5' means the oil is not as thick as a '10' or '15' grade oil at room temps. This means it won't take long at all to reach operating temps. At operating temps, the '60' grade is really a bees-dick in difference between a good '30' or '40' oil in terms of viscosity. It is very similar at operating temps. Really, it is more suited to racetracks, where oil temperatures are far higher than normal road driving due to engine being at full load constantly for long periods.

Its difficult to put a 'number' on the absolute optimum oil for each individual engine. Oil pump rates and pressure also play into it. For a well maintained engine, there is little need to stray from manufacturer recommendations.

How long is it taking to warm up? are you using an oil temp gauge to measure it?


Just use Penrite HPR10 or Syn 5 and stop fretting. lol

Shhhh you, go back to random chat where you belong if you dont like the discussion :P