What is the life expectancy of this truck?

i have a 2000 f-150 4.6L vin w ,extended cab 4 door.she has 303500 miles on her.had to replace heater core and transmission.the guy i bought the truck from said he put 2 transmissions in it.i have removed throttle body and cleaned the egr ports,very very very bad clogged with carbon.i had code P0401,egr insuff. flow for 8 months.first i got stupid and started throwing parts at it.new egr valve,pressure sensor,egr vaccum regulator,cleaned pipe going to exaust from egr valve with spray and coat hanger,cleared light and came right back on.thats when i started researching.found this is common on fords for the 2 passages in the throttle body to clog up,and i mean clog up.you will not spray it out,cause it is as hard as a rock.you have to either drill thru it or use scredriver and dig it out.i was shocked.step by step instructions on ford forums.take pics before and after and show everybody.also i have replaced iac valve,fixin to remove it and clean it also,carbon will build up some in it also.do not use brake cleaner,use throttle body cleaner or carb. cleaner,let it dry good before reinstalling.also fixed odometer blackout problem.its a cold solder joint.step by step instructions on ford forums.replaced front upper control arm and lower ball joints,both sides,this is common on these fords also.replaced hood support lifts,easy.i found out if you research your problem,you will find that other people have had the same problem,and posted pics,videos on how to fix and lots of shortcut goodies.please research