Does this unit have limit switches on the mast to reduce speed when traveling while elevated? Most ele. units are set up this way.If so then he is right. If not check the data tag on the unit and see if any down rating info is on the tag that reflects any data for traveling / weight / height info. Fork length can also play a factor in speed/ height operations. Does your company set policy concerning this issue, if not you need to have a set policy in writing (black and white) to protect your self in case of an accident. Just let some law firm get a hold of this one. I have done my share of accident investigations and with no set in place policy in writing this can turn into a very expensive can of worms. The excuse is going to be that is how i always did it.