1st question I have a 89 F150 straight six and a 88 F150 302 will my computer harness for the 302 accept the computer from the striaght 6

2nd question my 302 tranny takes a long time to shift through the first couple off gears then when it does shift it shifts very hard any ideas

I would really appreciate any reliable info guys thanks.

 

This is tricky. Since this is first generation EEC IV, then it SHOULD work. The pinouts for all the sensors are the same. The only real question in my mind is that of injector drivers. Since this is first gen EEC IV, I would say yes, since the injectors are fired bank and bank, instead of SEFI.
As for the trans, is this a four or three speed? The AOD was a common choice on these, however, the venerable old C-6 was still around. It could conceivably have the very first year of the E4OD (yuck; that was a tough year for that trans). If it's an AOD (4 speed), it probably has a pressure problem, caused by sticking valves in the valve body. The valves are probably sticking due to fluid being well used (dare I say burnt), and possibly from friction material due to wear. These also had just a lot of AOD-isms, which would include governor wear. Sounds like a line pressure test is the best place to start. It may help to do a fluid/filter change. That would be a great place to start for the least money, as most of these problems required an overhaul to correct.
Please let us know!

 

Thanks for the info i appreciate it. Just let me make sure i understand, in a nutshell the tranny is shot! I might be able to relief a little of the problem with a fluid and filter change but overhaul is the way to go and the money really isnt worth it when i can get a used one for not much more money right.

 

Yes. I really don't recommend the old filter and fluid change, as usually this will mask other problems. Usually, in something this old, if you do the change, you take the sludge out that's holding it together.
And DON'T go with a used one, unless it was rebuilt very recently; you just don't know what you're getting into, and if you wish to continue running the truck, then the rebuild will cure any slipping or harsh shifting, if done correctly.
One thing; if this is the old AOD trans (the lighter duty trans), then I would recommend a 6 plate forward and direct clutch; this was the weak link of this trans (the direct) and was an easy problem to solve.
If it's an E4OD, make sure to put a good (multi-plate) torque convertor in it (well worth the extra money especially if you tow with it) and a shift kit, which gets rid of all the early year problems these had (like harsh/or super soft shifts.) In the earlier years with the old E4OD, when the TCC engaged, most customer thought it was actually a gear shift (yes, they really were that bad!). A shift kit solves the pressure problems and shifting problem that came with this trans.
Good luck!