engine oil usage

[maximus]

hi guys,

just like to know if anyone's using Mobil 10W30 or 10W40? i've heard that it gives you better mileage and lower fuel consumption compared to other brands. how true is it?

appreciate the help!

[sms777]

G'day and welcome to our forum maximus!
To answer your question it depends on what type of engine you have.
For late model multi valve multi cam engines the best oil is 10w30 or 10w40 or even 0w synthetic. These modern engines run lot closer tolerances and very delicate valve train so thinner oil is better.
If you own a dinosaur V8 however it is different story. Because all the internals lot heavier they require loser bearing clearences and to take up for it you have to run heavier oil.
I use Penrite HPR 40 which is 20W70. It is like honey and works well in big bore V8's. I recommend minimum 20W50 as long as it is not Woolworths brand. Castrol Edge 25W50 is one of the best and it is available any store.
Some drag racers even run diesel oil in their engines with no issues.
Bottom line is, old pushrod V8's heavy oil, modern ricers thin oil.

Cheers, Chris.  
 

[Jethro]

Bottom line is, old pushrod V8's heavy oil, modern ricers thin oil.

Cheers, Chris.  
  [/quote]

I like the therory 777 sounds simple to remember too::yeah::yeah::yeah::yeah::yeah::yeah:

[65muzzy]

What about modern engines that have 200,000 km.  Do you run a thicker oil?  I know it is a lot of mileage but its a FORD and they never die.  :shades:

[sms777]

What about modern engines that have 200,000 km.  Do you run a thicker oil?  I know it is a lot of mileage but its a FORD and they never die.  :shades:

If it is an overhead cam with hydraulic valve lash adjusters you still run the thin oil because they have very small orifices. Thick oil will not allow them to bleed down quick enough and could hang the valves open.
Basically any ricer or local car built after 2000 will need thin oil regardless of milage. I thought we were talking muscle cars here
I hope this clears it up.

Cheers, Chris.