I have a 1988 F150 with an automatic transmission. Basically, whenever I try to accelerate from a full stop, the transmission does not want to engage first gear. Shifting to from first to second or higher goes smoothly. But, when the transmission tries to downshift back to first gear, the transmission takes a few seconds to engage. Interestingly, after driving it for a few miles and letting the transmission warm up, the transmission would shift to first gear normally. I want to know the possible causes for this and if there is a solution that does not involve getting my transmission replaced.