ok bought the truck with a lot of bad parts in front end now i have replaced evorything in the front end but the steering gear and pitman the ball joints tie rods wheel bearings sway bar end links front axles both sides idler arm new front shocks senatrac new tires twice all 4 ballanced 5 times alligned 4 times new u joints in all axles i did notice that the upper ball joint was little loose so i tightened the bolt a little fixed it pass side. driver upper has a verry minnor play i did use cheap parts for this work got them on e bay what would cause a shake at 65-75 mph could i have a faulty whel bearng no noise i am lost please help firestone is trying to say that i have bad rear shocks then i have been told that they are good i have had it in the shop 5 times no one is giving me a straight answer been told that the gearbox needs to be replaced then i have other people saying that the gearbox is tight i have verry little play in the pitman arm been told that it is good and that would not cause my problem i am just trying to save some money here and get the shake to go away like i said i bought it with all front end parts needing replacement any ideas would be helpfull its a 2000 blazer ls with 135,000 miles on it thanks for all the help

 

Just going out on a limb here. You said no slack at the pitman arm but do you have any play in the stearing? if so check the stearing coloumn knuckle just above the stearing box. it wont be cheap to fix if thats your problem but just a problem ive had. but then again I have 230 k on mine.