Does your 1999-2000 Ford chassis motorhome start off slow from a stop and then downshifts and takes off normally?  Do you notice slow takeoff from a stop and maybe a bump when taking off?  Ford had an issue with this year motorhome and put out a Technical Service Bulletin (TSB) on this issue.  We have run into this several times and have the fix for it.  The fix takes about 3 hours to complete and your unit will start in first gear every time after this has been done, this will save wear and tear on your transmission and make your starts much smoother and stronger.