it all started two days ago when i was driving my truck for the first time in a week. Whenever i sharply turned my 2003 f250 7.3 to any direction at a slow speed it would feel as if my tires were rubbin on the body. This then turned into the feeling of my four wheel drive being on. i checked my hubs and they were on auto along with the 4x4 shift on the fly set to 2wd... so i didn't think this was the problem.. i jacked my truck up on the drivers side leaving the passenger tire on the concrete. i then twisted my front drive shaft and it did spin my passenger u-joint but NOT the drivers side. i twisted the drivers side (suspended in the air) u-joint and it did not turn. i figured it was the limited slip. I took it into to a local mechanics shop and we did a series of tests concerning why my 4x4 is on with both hubs on auto and the transfer case on 2wd. i knew the transfer case was on 2x4 because it spun the rear tires in loose gravel easly i do not hotrod my truck that was just a test...... we unhooked the vacuum tubes and they did have suction. with both tubes unhooked it still remained in 4x4... we figured both my hubs are bad at the same time (drivers side bieng 1 year old ...passenger very hard to twist bieng 10 years old) i drove it home and i then heard a rubbing almost metal to metal grinding under my seat area. this happened as i started vehicle and when i first apply throttle.. it then got worse as it sat for an hour. the noise even happens in neutral. the noise is constant and loud when i am in reverse.. please help transmission? transfer case? 4x4 hubs? the transmission is original 190,000 used for pulling heavy loads all of its life

 

You can drop your front driveshaft to help isolate the tx case or front axle.


If it still does it, pop your front auto hubs off with drive shaft removed and see if it still exists.


20 minute diagnosis.


Denny

 

Thanks man I did that and I found it was my hubs....now what I s with the rubbing /grinding from below me?

 

It happens when throttle is applied in neutral, park, drive and it is VERY bad in reverse

 

Glad you found the hub problem.


If I were you I would replace the hubs with milemarker or warn premium locking hubs. Eliminates a vacuum issue. If you do, search how. You must end the hoses to the hubs to retain vac. Very easy and well worth it.


As far as your grinding noise. Check the levels in all drive components. Sounds like your transfer case may be dry IMO. 20 minute job, just pull the plugs and stick your pinky in.


Let us know.


Denny

 

BTW.


If you have the front drive shaft off. Take off the rear shaft. Put your ebrake on and put it in allgears after you chalk the tires. You can lay under it and carefully listen to the eng, trans and tcase. Do it symptomatically in all gears. In 4 hi, 4lo, etc and log your results AFTER YOU check the fluid levels in the trans, tcase and engine.


Go get a mechanics stethoscope for 5 bucks and really tune your ear to it. You'll locate the noise.


Look at your driveline and make sure you don't have some hilljack muffler clamp rubbing on a drive component that someone installed before you married up.


When you pull your shafts, it's not a waste of time. That's an opp for you to really examine your u joints and replace. Lube. Or inspect.


Give it a shot. Levels first.


Denny

 

Could be limited slip in Rear doing that. Your issue does seem like front, but this post might help someone else looking to troubleshoot this.