Hey there Phoenixsteeler... Just wondering which units you are currently running?
Also, I really have to disagree about Walkers handling hills.... I run GHS units and they rule on hillsides... And the B and H models are supposed to be even better!
Speaking of the B and H models, they have 10mph top speeds... The GHS units also have a speed up kit but in all honesty from what I have seen it doesn't make a huge difference... Like Jrs. said... maybe 8.5mph
You might want to try checking your tire pressure as well.... This can affect tracking.
Are there some things that you can share that you like about Walkers? If you are running them and you put up the $ for a new or used one, I would assume you did your homework and there are some positive attributes that you can tell us about........