90 f150. when i switch to the rear fuel take the truck runs for

Sounds like something amis in the tank,like pump coming out of the fuel, check the pick up filter screen.

it sounds like the switching valve is no good and needs replacing.you can clamp off the fuel hose to the rear tank and just run off the front tank until you can get it repaired.

fuel tank selector switch

common on older high mileage fors to either have the switch go out or the intank pump go bad, you cang ground terminal 6 on the underhood diag plug with key on engine off and switch from front to rear or vice versa and listen for fuel pumps to be running, likely one is not

Does you truck restart after dying and then run ok or does it stay dead until switching back to the rear tank?
It could be that the front tank has a leak in the suction line which will leak when not in use and **** air when you switch to it.
A suction air leak could be the reason for it dying when switching tanks

you are going to have to replace the in tank low pressure fuel pump, we call this the "lift" pump.

It Maybe The Fuel Tank Selector Valve On The Frame Rail That Switch From From Tank To The Rear

your truck is a 4.9L, make sure you have power to the front tank fuel pump. is the power to the pump is ok and you can hear the pump run for a second or two when you key the vehicle on... replace the fuel tank selector valve

There is no selector valve on a 1995 ford f150 300 engine. The selector switch on the dash sends power to the pump in the selected tank. The pump then sends fuel to the engine. If engine won't run on the selected switch, the pump in that tank needs replaced.

Your truck is fuel injected. On the fuel delivery rail in the engine compartment there is a cap you can take off to check for fuel pressure. Hook a mechanical gage to it and check to make sure the fuel pump is working. Also if you have a dash switch to change over to the different tanks check it. Often these switches become bad and the fuel will not flow. The switches are about $ 40.00 dollars. To replace the fuel pumps you must drop the fuel tanks and remove each fuel pump from the tank. The cost for the pumps alone will be about $300.00 to $ 500.00 depending on who you purchase them from. The universals are cheaper, but the Ford pumps are an exact match and you can change them with out any problems.