5W-40 is going to be to thin for the A series, and you'll be hearing a lot of tappet noise. For R100 a pop on Havoline 20W-50 I would even say change the oil every 6 months if you could, you'll be paying R200 for 2 oil changes, which is less than what you'll be paying for the synthetic. You don't have to change the filter every time though, every second time would be sufficient, though at R28 a pop, you might as well...

You are actually answering yourself in one of you earlier comments. The car is not being driven much, and that causes petrol and moisture to build up in the pan and system. So even if the oil might be fine, it could be contaminated enough with said elements, that it doesn't lubricate the engine properly. Only frequent longish trips would abolish enough contaminants that the oil would be restored to it's original state, which I don't se happening in you case.

Honestly, knowing you as a "worrier", I would have expected you to ask how many oil changes per year are to many...

You should also rather run at least a 10W-60 or something similar on you Almera, it must have a higher upper sealing than 40 whatever you get. Remember, the 5W-40 won't have such a high temperature tolerance as the one I mentioned, and you might find that the oil pressure starts falling on those very hot Free-State days.

Those oils are meant for very cold climates where you don't get 30-40 degree heat, and thicker oils would cause hard starting and high wear.

A little of the topic, my dad used to race oval track cars. They would rebuild the engine, fit the sump and weld the drain plug shut, for fear of it vibrating loose. I remember one time they raced a whole season without changing the oil once, simply because that would require the sump to be removed. On those old Ford Kent engines they didn't use valve stem seals either, so it used oil fast enough that they had to fill it up with about 500ml of oil after each meeting, which sort of ensured that it had a semi permanent oil change...

Thanks for the replies guys.
Currently the Datto is running a Mineral oil of Engen Xtreme 15W-40. My father and myself get them from Engen's depot at cost price which comes out lower than R100 ZA rand for 5 liters. The Almera is currently running Mobil1 which I think is 0W-40. It runs without problems and have been running it for the past 50 000 to 60 000km.
Think I am gonna stick with Engen Synthetic in the Almera not to mix mineral and synthetic and gonna stick with the mineral in the Datto and change on a yearly basis.

Hi all, Ive used mobil 1 5w 50 snth. for the last 100,000 kms exclusively and very happy, it is an a15,slighty worked on straight lpg and often driven hard.
Cheers.

0w anything causes lifter problems in SR20's after some time, its not such a big thing with the roller rocker low port, but it will happen, rather stick to a 10w40 or 10w60, I use Castrol SLX in all my SR20's and RB's and while it does about crack the bank in half it also lasts one whole bunch longer (its the same oil as volvo and similar recomend for their 20 000km services even on their T4 and T5 turbo motors)

Just what ever you do steer WAY clear of Castrol edge, I lost two 350+wkw SR20's thanks to that rubbish before I realised how bad it foams.

i run castrol 5w20...bit to light i think as it uses the oil and i have to top it up atleast once every 3months and i am waiting for the day i do a clutch...accutaly better change it soon

Castrol edge 5w30 use to change it once every 6 months.... but now only once a year.... because of school!