Oil £10 for 4L

No idea. They had a pallet full of it in the shop.

That is supposedly 5l rather than 4l though.

I don't think so, that would be very odd if this was the case. Halfords sells ther own brand oils in 4L bottles, not 5L.

Nope the stuff at the back of the shop was 5L at full price and the at the front on offer 4L.

They sell it in many sizes, including 5 litres.

OK your right, it's also on the website. But why are the Halfords 4L and 5L oil bottles the same size? I noticed that the Halfords 4L bottle was much larger than the Tesco 4L oil bottle.

Ok, so they had me this time, grrr. Still cheap offer though.

Yeah you're quite right. However the Halfords 4L and 5L plastic bottles are of similar height, hence my mistake.

The volume height to the shoulder of the Halford's 4L bottle, excluding cap and handle, is 30cm. But the oil in the bottle raises to only 18cm, as can be seen through the transparent strip on the side!

Why indeed? People don't tend to forget that sort of con. And go elsewhere next time.

Yeah Halfords is the last resort, there are many smaller independent shops. What also annoys me is that Halfords have now put many more standard items behind a 'parts' desk, so you can no longer browse the shelves for suitability and price, it can only be handled through 'we know best' staff. It has become something as a joke, e.g.their offers to fit windscreen wipers or bulbs at a cost. Who needs that?

After the torture I endured replacing a couple of Ka headlight bulbs, me.

And that's called 'progress' :)