In article ,
Harry Bloomfield writes:
I bought and fitted two covers rated 3 ton, they permanently deformed
under the weight of one wheel of my car, the very first time I drove
over them. Supplier had to swap them FOC for 5 ton rated ones, which
luckily fitted in the same frame.

I bought a 3 ton one to replace a broken one in the alley round to
the back of the house. It was galvanised pressed steel, IIRC. It
let out a laud "poing-ping" when you stepped on it. Took it back and
got a proper cast iron one (can't remember if it was 7 or 10 ton).
That was much better, and not much more expensive (although I also
had to buy lifting handles for it).

--
Andrew Gabriel