I’ve got Shimano LX disc brakes which use mineral oil (one of the reasons I went for Shimano is that mineral oil is meant to be non-corrosive for numpties like me that tend to spill things and make a mess).

If I were to buy some generic mineral oil for these brakes what DOT designation would I need? I suspect that you shouldn’t mix types but apparently DOT 4 and DOT 5.1 are both mineral based, can I use either? Which is the more corrosive stuff used by other manufacturers?

Citroen mineral oil from Halfords works, don’t think mineral oil is DOT?

DOT fluis is not mineral oil, it would eat your brakes

I would try with virgin olive oil.

Good job I asked then. I looked here which states that DOT 3,4 and 5.1 are mineral based (and 5 is silicone based) but that doesn’t sound as if it’s the same as mineral oil.

Yeah, mineral oil is basically just oil, DOT 3, 4 and 5.1 is I think largely ethylene glycol.

TBH, if you have a local halfords with a bikehut in it, it should have the little tubs of brake fluid, they’re reasonably priced and do the job perfectly. You can get cheaper per mm but there’s no point buying a huge bottle, the brake systems don’t hold much fluid.

I’ve used the stuff from a Citreon garage before, that works fine. But as above, no point buying more than you need.

Citroen LMH is fine. Shitmano will tell you they have all sorts of speshul additives so they can sell you it for 10x the price. Just get the smallest bottle of LHM fro helfrauds

I don’t need loads of course, but the tiny little Shimano bleed kits seem a bit over priced at around nine quid for 50ml when you can buy a litre of the stuff for £13. I’d imagine a litre of the stuff would sit around for ages possibly absorbing water (does mineral oil do that or is that just DOT fluid).

Pjay – not nearly as badly as Dot fluid does IIRC.

I use the Halfords LHM Citroen stuff, but I do think it is a bit thicker than the OEM Shimano stuff.