Correct / Recommended oil

[Boomtown1]

Shell helix ultra for me 0w 30
£60 for 6 litres

[Kev0607]

Originally Posted by JamesS44

I've used Castrol Edge A5/B5 for the last couple of years, but seriously considering using Smith and Allen A5/B5 which is extremely good value at £64.49 for 20litres on Ebay

I have used Smith and Allen for g/box, diff and power steering fluids so far and no complaint from me.

https://www.smithandallan.com/produc...car-motor-oil/

Anyone used Smith and Allen A5/B5 for engine oil?

I haven't used Smith & Allen engine oil, but the trans fluids they do are decent & have been highly recommended. I don't think it really matters what brand of engine oil you use, its the viscosity (0w-30) & spec (A5/B5) that really matters.

There's better value options than Castrol for oil... Smith & Allen is one of them.

[AndyV7o]

Just bear in mind that cheap oils use cheap additives and 'b' grade base stocks. The result of this is that they seldom retain viscosity and spec throughout an extended oci. Up to 10k theyll be ok, 18k there's a high likelihood you have been running on acidic low viscosity low hths oil which has started leaving deposits as it cant hold them in suspension any longer, or sticky, gummy, oxidised oil thats coating various parts in varnish, in addition to the above.
Now without used/virgin oil analysis over multiple changes and drivers/vehicles, we vannot be said for sure which brand lasts for how long, but, it is known that as above lower quality base oils and additives can and do break down early
Smith & Allen are interesting, they by their stock from shell, its not shell's extremely good gtl stock, again, itll be the stuff they dont use (which could be stuff that doesn't meet their stringent qc for premium oii, or, stuff they have lots of but use little of because it isnt of use for many of their products) that said, it still may be decent stock for a budget oil. We dont know what/who's additives are used.
Whilst using cheap oil isnt going to cause an instant painful engine death, it is wise practice to halve the oci if using it. That said, even flagship oils are struggling by 18k.
Roughly speaking, dependent on variables, the ideal maximum lifespan of oils is around 8-10k for cheap (though there are some I wouldnt go more than 6k) and 15-16k for premium.
Also, bear in mind 'meets' and 'approved' on the oils spec. Most cheap oils 'meet' but arent 'approved' which means they are claiming to be up to spec, but nobody has tested or verified this to be true. Approved is certified to meet spec. Approved oils cost a lot more because the approval has to be paid for in addition to the more costly ingredients.
So buying cheap oil is like making a banggood or wish purchase, it may or may not do what it says on the tin, you just dont know!
There are also those who think 'its all the same, it comes into the country on the same boat' no, there are a few big 'boats' from a few big crude sources, and yes most oil -made here- comes from one or the other 'big boats' but that is refracted crude, waaaaay before it becomes base oil, waaaaay before that then becomes engine oil, the final product can vary wildly.

At the end of the day, its down to the viewpoint of the person paying for and driving the vehicle, but its better if that decision is reached with a more comprehensive knowledge.
Yer pays yer money....