Is the tail light harness for a 87 f150,250,350 the same as a tail light harness for a 91 f350?

 

Even if they're not, you probably wouldn't have to make any extreme modifications- maybe change out the light sockets- but the primary wiring should be the same.

 

no they are not. different plug ends on the truck side and the bulb side.
the 87 uses 1157 bulbs. the 91 uses 3157 bulbs.

 

thanks. That's what I needed to know.

 

What year did they change?

 

88. the 87 uses a flat truck side plug and the 88 has a round truck side plug. i think. one or the other. i do know this though because in the spring when i went to pick up the 87 bed to put on the 88 i did not bring the 88 rear wires thinking they were the same.
so i had to drive home with the magnet mount trailer lights.

that was when i also found out about the bulbs, and had to repair the fubared 88 harness.

 

What years will work for a 91?

 

My 1988 diesel donor truck has considerably different harnesses throughout the truck than my 1991 does. The wires are mostly the same but the plugs are not.

 

Ford told me today that 90-96 are the same.

 

Any ideas on where to get a new harness?

 

Which part are you needing and do you need one for an 87 or for a 91?

 

I need the whole rear harness. From where it plugs into the main harness that comes from the front. I need it for a 91 F350. Would like to find NOS if possible.

 

So... like I said, he may need to make minor changes like putting new bulb sockets on, but the basic wiring is the same....