Thanks for the input,Mike! i posted the same thing,this Spring,when I found mine has the same problem.,('55 6500 T.F.). The funny,(NOT)!! part is,that the 1955 Chevy Truck Service Manual,(for that year,anyway),DOES NOT cover anything pertaining to the vacuum-shift 2-speed switch,adapter for "speedo",or the "pancake"!! Very little info.,on the hydrovac,vacuum system,although the BRAKE system is pretty thorough. G.M. must've thought that the vacuum systems would out-last the trucks?? The reason I purchased the shop manual in the first place,was for info. on the 2-speed configuration,(on my truck),since the "PO" removed the switch from the transmission,and had a hanger wire attached to the "pancake",to change gears! Is 3375765,the one used on the T.F.'s as well?? THANKS!!
