i have an old hyster, the tag is all smashed so i dont know the numbers on it. it looks like a h40xmm ser. h177g538090b that i worked on awhile back. it has the three mast lift cylinders on it. where can i find id numbers on it? im thinking i need to reseal the cylinders. when i lower the forks they creep down a few inches after i let the lever go. tried all kinds of lever action but it still creeps down a few inches. does it with or without a load. when i raise the forks it may creep down a few milimeters after stopping. it dosent seem to be the valve so im thinking cylinders. it does it on all cylinders. also the center cylinder will go up after the twins go up with a load on it. dont know if that could be a root cause to my problem.