Go to this web site: TREK Tracks There is a wealth of information on Safari TREKS, including replacement bed motors and repair techniques. There are many TREK experts on that forum who will be glad to help you.
A former TREKer
2004 Country Coach Allure 33' Cummins 370HP ISL
400 Watt Solar Array M&G Braking System
2003 Honda Element (and as many canoes as I can carry!)