dot 3or 4 used on these old dogs. i would change both wheel cylinders. guarenteed the other side will go shortly.

thanks for your replies, reason i asked is that i fit new m/cyl early dec and now 1 wheel cyl has started leaking. It may just be coincidence, but i filled it back up with brake fluid.
when i ordered new cylinder from tvh there was warning about correct fluid.
I think the cylinders are correct because there is only 1 that measures up (1" bore) but I also started looking at master cylinders on tvh and noticed that all kalmar m/cyls list brake fluid.
dont want to fit new wheel cyl and that to go belly up in another 2 months!!!
things like that get you a bad name quickly (and cost you money)

I am fairly sure the that Kalmar have never made any small machines. The ones bearing their name are just badged up machines from other manufactures. Which will usually be either Climax or TCM both of which would use normal brake fluid. It may pay to check if TVH have sent you the correct part.

i used to work on those trucks a few years back and always used standard dot 3 brake fluid. now a days though there are many cylinders that use mineral based oils,so be a bit careful.Always read maintainance where you can

well ducks some master cylinders do use mineral oil different seals that will not be damaged ie swelling i am not sure on your truck any chance of taking a sample from wheel cylinders