I have a 1968 C-10 pick-up truck with a 237, 400 automictic transmission in it. Have had it for about 2 months. It has, at the radator, rubber hoses that are conneckted to the 5/16 metal tranmission lines. I guess someone in the pass change the radator. Could not get lines off old radator. So cut the metal lines and replace them with the 5/16 rubber hoses. I never did like it but figure it would be okay untill I pulled motor out this comming summer and put new lines in when the motor was out of truck. The other night, the top hose came off. Transmission went eveywhere. I seen that the metal peace that was in radator was only a short part of cut off line. So I bought two of those brass fittings with the big flare and put them in radator and also put on two new 5/16" rubber hoses. The top hose is about 12" long. The bottom hose is about 6" long. It looked to me like the old hoses had been on there a very long time. maybe 5 years or so. So I started thinking maybe the hose just did,nt come off. But maybe the presssure in the cooling lines got real high and blew it off. Pressure in the cooling lines is somthing I,ve never thought about before. Will the pressure in these lines go way up at times for some reason. Shold I not wait untill this summer to replace with new lines. But do it now. How would you advise me. Thanks John.