I originally posted this on another forum but Answers have been slow coming and am no closer to a resolution as i am still puzzled at this point. But i have been able to eliminate some things.

Description of the main problem ive been trying to fix if possible.

Problem ive been having is since getting the truck when in 4wd for like snowy and off road stuff, ive noticed over time its becoming harder to make turns when its all locked in.. please understand I do understand your not supposed to make sharp turns with the front end locked in.. thats not what im meaning.. I mean like when making wide turns that should not be causing any issues with an Open Differential its acting like it doesnt want the wheels turned. (for example making a wide left or right turn across a 4/8 lane road onto another 4/8 lane road..) Its almost like the front ends binding up and trying to straighten the wheels back out.. i cant even turn the steering wheel 1/4 revolution anymore before i start feeling this.. (feels as if someones pulling hard on the wheel the opposite direction) at 1/2 a turn it feels alot stronger. ive had people tell me this is normal but for a open diff but doesnt seem right when your rear diffs dont do this in turns. i was making a severe/sharper turn like if i was trying to do a u-turn on a 2 lane road i could understand it.. It wasnt this bad when i first got it the truck i could turn turn the wheel 3/4-full rotation before feeling even a little bump in the wheel. With the T-case in 2wd i can turn a little further before feeling it start.. but locked in i almost cant turn at all.

i know its not the U-joints as they all the ones from the transfer case forward have been replace... The hub locks have been replaced with Yukon Hard Core locks but the problem was there prior to that. I got rid of the factory ones because they kept freezing up both in locked and unlocked despite how many times i tried regreasing them.

When ive taken it to the dealer they just kind of dismiss me saying its normal.. I dont think they ever actually ever looked at it.

The video is not mine but shows pretty good what i feel in the steering wheel.. but i think they have the wheel cocked further than i do when im feeling it in mine.




New problems thats shown up recently.

Recently when i had it all locked in the front had a loud whine similar to how my rear axle sounded when the R&P beat the crap out of each other. Loud and whiney like the old gearboxes on the Woody trucks.. I originally thought this was a sign that maybe the front diffs doing the same as the rear did.. But after checking it the other day i didnt have any play in the pinion.. if the hubs are unlocked or only locked and still in 2wd for the t-case its quiet.. lock in the driveshaft in it starts the wine.

I had some suggest it could be the hub bearings causing the whine and the resistance ive been feeling but when i checked the axles for play they only wiggle about 1/8".. Videos i found showed way more play when the inner hub bearings were gone. The passenger side hub was replaced either last year or the year before as it was making a loud humming even in 2wd without it being locked.

when i checked the fluid level a couple months ago in the diff it was right at the bottom of the fill plug... little even dripped out when i pulled it... friend had suggested putting some limited slip additive in there to quiet it down even though its an open diff.. but didnt seem to have an effect..

wondering if i should pull the cover off and refill it with new gear oil... especially after adding the Lslip stuff... its been done twice since i got the truck.. once when i first got it because it was very chocolate milky looking.. (a ford tech told me that the color was normal looking if it was the original gear oil due to their special additives they use. but dont know if it was the original stuff at that time)... then was done again after the shaft seal went on the passenger side.

The Transfer case has had the fluid changed twice since i got it.. First time right when i got it as it was a Dark Burgundy color.. then again after about 1000 or so miles because i wanted to try and flush/wash all the old fluid out and off the gears as best i could without doing a full tear down.

 

Forgot to meantion i do not have SOTF.. Manual T case with Manual hubs..

 

Checked the fluid level in the front axle.. still full.. but could not check the transfer case.. the fill plugs atm is frozen in there and wasnt in the mood to try working it out tonight...

 

Any time you turn the wheel while in 4 wheel drive this is normal. What you are experiencing is the velocity chance due to the angle of the steering joint. This will provide a shake and pull in the steering. The video shows that, also note you can physically see the wheel speed differ during the rotation. Rather than explain the physics of what's going on, you can google it if you're that interested in u-joint velocity and phase. This isn't experienced in a rear axle being there are no u-joints. Unless something is grinding or it rips the wheel out of you hand then you either have a locker you didn't know about or something is broke and binding the diff. I doubt that's your case. It's totally normal.

 

why would it be starting sooner overtime then?? would think if it was normal id be feeling it in the wheel at the same spot in the steering wheel position instead of it changing.. like i mentioned above.. when i first got the truck i could turn the wheel 3/4 of a full rotation before feeling it start to lightly resist the wheel turned.. now i cant turn the wheel even 1/4 the way before feeling it start to do that.. at half a turn it trying to rip it from my hands..

 

have you jacked up the front end and verified that your differential isn't fubar?


what happens if you unlock one of your hubs? does the feeling go away?


serving ideas.

 

Without seeing it or driving it, you are going to get someone's guess where to look. You need to work your way through and inspect everything. New fluid or additive isn't going to fix it. No need for limited slip additive in an open diff. Are there any u-joints binding, doesn't matter if they are new. You are sure the wheel bearings are good. Pull the cover and actually inspect the differential. Are the spider, cross pin and case in good shape? Without driving it, it's tough to say. Depending on the available traction while you are driving this could be completely normal, but you feel it's not; you need to investigate where the issue is.

 

would it even work if one of them was unlocked??

i havent had the time to pull the cover yet.. and now the grounds covered in ice and snow..

suggestions is part of the point for these kinds of threads.. usually because the one asking has run out of ideas in where to look.

the only reason i put the limited slip additive in was i had someone else suggest it saying it cleared up similar issues to what i was experiencing at the time... while it quieted down the front a little for a short period of time its since returned and seems to be getting louder each time ive had to use it... anything over 40 it hums pretty good if the front shafts locked in with everything.. which it only started doing the hum recently.. originally thought it was an issue with the pinion bearing but wasnt loose at all...

ive watched the ujoints with the front off the ground and turning by hand... no audible noises or grinding sounds from either side like people say to listen for... checked the shafts for lateral movement as others suggested bad hub bearings (apparently theyre only good for 20K miles), only get an 1/8" at most been told that part is normal.. if they were sloppier i could suspect them...

i had another 4x4 years ago but never had any problems with it so i never had to touch the front end on it.. (unless you count with the tie rods went bad)... the two things i can say is similar between the 2 ive experienced is when the hubs are locked but still in 2wd you can feel a slight drag like the front brakes are dragging slightly... and anything close to highway speeds ill get a vibration in the steering wheel like its got an unbalanced tire... so figure both of those are normal feeling...