John Deere 6675 won't hold boom down pressure

[snonbos]

I recently picked up a John Deere 6675. I have noticed that if you put down pressure on the boom, for example tilting the bucket down and leveling or going into a packed dirt, the boom will not hold down pressure and will bounce up and down depending on resistance going forward. If you push the boom down pedal again it will bring the front wheels up again but it still isn't solid. My thought was air in the cylinders somehow but all the other cylinder actions seem solid. If it was going into float then I assume then there would be no boom down pressure at all? Any ideas? Thanks.

 

[chrimsun]

My 6675 does not want to hold the boom up occasionally and you have to work it up and down until the seal(s) push out the air . It doesn't do it constantly, but it still annoying.