I just bought a Bobcat 440B and I have a few questions about it. First, a little backround....This is the first skid steer I've ever owned (or driven), so I'm not familar with them at all. I've owned an older Massey full size backhoe for about 6 years, so I'm not totally new to this kind of equipment, but I know nothing about skid steers. These are used around the house only, I'm not a contractor or anything like that. I'm mechanically inclined and work on my own equipment. I own a muscle car and motorcycles, so I frequently go to forums for help and advise. I was glad to find this site and spent a lot of time reading the posts last night. I must say that what you guys have going here is very good, I learned a lot (but I didn't see any posts on the questions I have!). The 440 is in pretty good shape and has a replacement engine in it. The previous owner said he had to replace the engine because fuel 'leaked' into the carb and engine when it sat for a few weeks, and when he started it the engine "blew". The Kohler sticker on the M18QS engine says 'Export or Replacement Engine', so I'm sure he's telling the truth. He put a ball valve on the fuel line to shut the fuel off so it wouldn't happen again. I've gone over it pretty good - pressure washed it, changed the spark plugs and oil, and greased everything. I really haven't found anything wrong in that respect. The old plugs looked good, the old oil looked good, and it took grease in every fitting. I think it was well maintained. Here are my questions.... It has Titan HD 2000 Rim Guard tires on the front and Solideal tires on the back. All four are 23x8.5-12 six ply tires and all four have 4/32 tread. But the front tires are 23 1/4" high and the rears are 22" high. Does it matter that the front tires are 1-1/4" taller than the rear tires? Standard tire size listed in the specs is 5.70x12, is a 23x8.5 the same or at least ok? It has 'herky-jerky' big time (bobs up and down). On a hard surface it's really bad, on dirt it's not so bad and easier to get under control. Is the unequal tire diameter causing this, or is it something else? Is there any way I can determine what year this is? The previous owner guessed it was a 1981, but he wasn't sure. Thanks for the help guys, it's very much appreciated!