I need to replace the front bearing hubs

I have a problem with my ft hubs not locking in the axles turn when put in 4 wheel but the hubs wont lock in. I cant find anything that tells me where the soliniod is that controls the vacume

Easy check procedure to see if hubs are good jack up front tire and turn tire to access front of fender well then remove vacume hose from truck to wheel with truck off and suck on hose holding pressure in the line. Sounds wrong but trusted if you do and pressure remains in line hub could be locking so then while holding pressure turn tire to see if its locked. If the line does not hold pressure the hub is bad an needs replaced if it locks in you elimenated hubs from problem which is first place to check also check both sides because if one leaks both will let loose because the vacume runs from the same actuator pressurising both at once

The vacume silinoid on my ranger wich is 98 is under the right side of the front of truck behind bumper if you trace the vacume hose from the right hub back to the source it should run to a hose splitter 1 to 2 hoses wich comes from silinoid to splitter then a hose to each hub

You can also check the silinoid by removing the splitter so you only have the one hose coming from silinoid and starting the truck and having someone engage the 4 wheel but the vacume only pressure up for maybe 10 sec because it takes verry little vac to engage the hubs and once the lines are pressured the silinoid kicks out holding the pressure in the lines stoping the actual vac from engine so its best to be ready to check the vac from silinoid haven someone else in truck because of the short amount of time. If the 4 wheel is engaged and no vac then you have a vacume issue and it doesnt actually mean its the silinoid but your a step closer if you have vacume then your hubs would be next to check

So my front left hub has been giving me issues for some time, it was making a high pitched humming noise at any speed over 10mph. I had it changed and then shortly after my four wheel drive refused to work at all. Turns out the hub and bearings went bad, as well as the electronic relay switch which could engage and disengage 4x4. Changed it all out again. Was working fine for a while, but now the high humming noise is back and even worse there is a lower noise that sounds as if there is some friction coming from the left hub. Additionally the front left axle is spinning as if 4x4 is engaged, while the right side is fine.

Would a bad lower ball joint on my 1994 ford ranger xlt cause pressure and wear on the wheel bearing and creating heat enough that it would melt the locking hub for the four wheel drive? There was a clicking noise front passenger wheel that I noticed and quickly worsened, I then noticed the locking hub looked melted which it is. I jacked it up removed wheel and locking hub, the wheel bearing feels tight however the lower ball joint is extremely loose. Would that cause pressure on wheel bearings?

Well I got the truck about 5 month's ago, at first the brakes started to lock up every once in awhile then their was a noise that started coming from the left front tire. It sounded like something was stuck in my tire like a swishing sound. So I replaced the breaks, outer bearings, calipers rotors were in good shape. Well it helped for about 3 days then all started again but now my abs light is on and my tire shakes a little bit and when I put my truck in 4 wheel drive you can here a bad noise coming from that tire but 4 wheel drive works. Can someone please help me out!