i was chatting with an autoperfoormance place and this is what they said
Simon: Welcome to Live Help! How can I assist you today?
jason: i am looking for a part # for the moog upper and lower ball joints on a 99 ford f-250 7.3l
Simon: Please allow me to look into the information for you. Would you mind holding a moment?
jason: no problem
Simon: I'm sorry for the delay. I am checking the information for you! Please bear with me....
Simon: Is this a 2-wheel drive or 4-wheel drive model?
Simon: Under 8500 GVW or With Twin I-Beam Axle or Enhanced Design or Under 8500 GVW, Enhanced Design?
jason: how do i tell if it is twin i beam
Simon: I apologize, I am not that familiar with this particular information. I suggest you check with the local dealer or local mechanic.
how do i tell if i have a twin i beam or not