I have this craftsman "professional" 3.5 ton floor jack my dad gave to me years ago for my birthday, it was a the kind that would raise fast until it hit a load. The speed pump stopped working after about a year old, and it's made in China! then it always went up slow, now all these years later this is as high as it will go, the oil was full, I took the rubber plug out of the cylinder, pumped it, took the oil plug out to see if any air was in it, no matter what I do the jack won't work. Now, this jack is only used a few times a year, I'm not running a garage were its used everyday. Any ideas? I watched utube and Google but nothing seems to work, worse case I'm thinking of getting a aluminum one from harbor fraud, I can't lift this steel one from the ground into my trucks.