Hello, Would like your ideas on the following: my 59 GMC 660 (gas 503ci) heavy duty truck went for a road trip today, first time in twenty years, but offroad exercised yearly. Its 5 spd Spicer has always shifted fine but after a little workout, up some hills, she won't shift into first (shifts fine thru the rest of the gears). I'm thinking clutch rod adjustment is in order, or could it be something else?
