Ok so about a year ago I bought a 1992 f150 XT 4x4 with the 302. Unfortunately something has gone Ary and it loses oil pressure when it warms up. I have decided to swap motors but I am unsure if the donor motor will actually work. The donor vehicle is a 1991 ltd/crown vic. At first glance I thought it should go right in but upon closer inspection the valve covers seem to be shorter on the crown vic motor which leads me to think that it might not just drop in. I'm thinking it will be fine as long as I switch the exhaust manifolds and upper intake and I was entertaining the idea of going with chrome valve covers but if it's not the same as the truck motor I won't even bother. So any advice here would help.

 

Before you put a new engine in, make sure it has the right oil in it. If the oil in it is too thin, it'll lose pressure only after warming up. I run into this from time to time. Normally somebody went to a quick lube shop for an oil change and the 'techs' there will put anything in just because it says oil on the jug. lol

 

When you get down to the basic motor, they're the same thing if they're both 302's. You just have to change over all the outside dressing. Oil pan, valve covers, intakes, front accessories etc.
Which you probably would want to do anyway so you can put new gaskets in.
It will probably have a power cam in it so you lose a little torque.
But - block and heads, 302's a 302