Thank you for the suggestion, I did as you wrote before I posted the question and the shift lever aligns perfectly, the low shift seems a little stiff and takes a little extra effort to get into gear especially cold, I am wondering if the cables should be lubed to help it? The adjustment under the dump box is good also, I am thinking that when I am plowing and push into a snow bank the gears are all pushing forward and when I let off throttle the machine rolls back just a tad when I shift into reverse and either the gears are not fully engaged or the rear locker is sticky and causing the bang as it engages fully. It feels like the bang is right in the middle under the seat. The wife and I went on a 100 km (60 mile) ride yesterday on the snow plowed back roads and it ran and drove like a new one even tho it has 24,631km on it. The service wrench came on while we were out so I think I will change diff oils as well this time to see what that shows.
Any other suggestions?