Tipper Hydraulic problem... help!

[James905]

I have a 3 stage Hydraulic Ram on my tipping body.

It goes up fine no problem, never struggles, on the way down sometimes the 2nd stage doesn't fully go down before the final section does, what happens then is when it gets to the last 1foot or so, the whole thing just drops like there's no pressure at all.

Sometimes I end up going up and down about 6 times before if finally does it properly to avoid the drop 

 

Any ideas?