FROSTY , is your Dob an f8 , 1200mm focal length? , if so an HEQ5 would be the very , very minimum , EQ6 better but sadly these mounts in GOTO mode start at about $750 2nd hand , up to $1200 ish for the EQ6 ,
I use the HEQ5 for both my 127mm iStar frak and Celestron C9.25 Cat and it holds these well but the length ( not so much weight) is the problem here , with mounting an OTA of 1200mm long it takes a very solid mount ( $$$$ ) the torque so easily applied in use is the problem , hence why most large Newtonion's are mounted Dobsonion wise .
Ps. maybe the Mod's move this thread to 'Beginners EQ discussions '? will get a better response there I think .
Brian.