I am needing some advise from some of you with a little knowledge. I am very knowledgeable, but am stumpted here. I have a 89 F250 with the 5.8 that I just bought for a plow truck. It is 4x4 auto.

Now the problem I am having is the truck has No power. I have changed the whole fuel system, from tank to the fuel filter. Using the same lines that are in good condition, both pumps and filter replaced. The pressure at idle is 35-38 psi. With the pressure reg vacum line unlpluged it reads 44-45. So I am guessing that the fuel system is good.

It starts fine, idles fine, revs good, but when I put a load on it, the truck will move, but like someone is brake torqueing. I put the truck in nuetral and it rolls fine, so I am guessing that there is nothing hanging up such as a brake or drive train.

I have not jumped into the ignition system yet, but it is not stumbling or hesitating not does it have any misfire going on. The engine sounds good. I will be replacing the plugs, wires and cap, but I already have a couple of hundred bucks into this and would like to find out what is wrong.

Now the truck will not go into 4wd at the moment, but i dont think that would have anything to do with it, but I am not a expert on trannys. That is what I am mainly asking about. The trans is a c6 and appears to shift good from what I can tell. It does not slip, that is not what is happening. The feeling that I get is like a brake toruqe without letting up on the brakes.

The truck will drive and pull itself up a hill, but it has to be floored, the rear tire will even spin a little(in the gravel) , but this thing has nowhere near the power is should. I have a E350 with the same motor that runs ***** to the wall.

With all this being said, the CEL is not lit up, but am going to read codes anyway. The whole air system under the hood has been messed with and there are many vacumn tubes in dissaray. But again, the motor idles like brand new. No misses to indicate a vacumn leak and the motor will rev under load.

I was wondering if the tranny had a torque lock or something that gets hung up and causes the truck to do this, BTW if I am driving it in (D) drive, and floor it while the truck shifts into second gear, the truck will downshift into first as it should.

I know this is long and winded, but any help would be greatly appreciated. I am very knowledgeable, but am stumped...or mayby lazy I dont know.

Thanks
Rich