Last year, I noticed a noise whenever I would engage the hubs (in our out of 4WD). It was noticeable around 55, so I just kept it around 50 or below if I had the hubs locked in. Haven't seen any issues.

This summer, I did a complete brake job (repacked bearings as well). I've only had the hubs locked in once this winter (truck was in the shop for a month ... long story ... might start another thread). Now that I'm driving it again, whenever I lock in the hubs, the noise is really bad. It's not a grinding noise, but a loud moan.

I put the truck in 4HI this morning on my way to work (without locking hubs) and did not hear the noise at all.

Do I need to replace the locking hubs then? Which ones should I get? I hear pretty much everyone talk about Warn hubs. I don't want to spend a ton of money (don't have any to spend after last go around). I drive all highway and have yet to go offroading or tow anything in 4WD.

I'm thinking I would be ok with the OE style Warn replacements?

 

I would be thinking axle u joints.

 

With a moan, that would lead me to think it has something more to do with the differential or transfer case. Reason being, you took the hub bearings out and repacked them. If there was any kind of an issue there, you should have seen metallic flake all in the grease, and wear marks on the bearings, even the races.

You also left the hubs disengaged when you got that moan as well. If you have the hubs unlocked, its free spooling and no torque being transfered to the wheels. And you still get the noise. Now had the noise only come about when locked in, yeah.. you may have a hub issue to look at.

I know that differentials, transmissions and tranfercases make more of a moan noise. If you had bad U-joints, you would get vibration like a monster! LOL! And as recently discussed by other members, you would loose a driveline!

Here is some tips to help further diagnose your moan issue..
- Remove the front drive line. Drive it again, and place it into 4wd. Listen carefully if the moan is coming from the front end or from under your truck.
- Check the condition of the fluids in both the front differentail and the transfer case. Look for that flake I was talking about. If you remove the front diff cover, look for heat marks on the ring gear. It is a blue type color. I dont think you will, but its always a good idea to examine it while you have the cover off.

Run the test with the front drive line off.. I would be very interested to see what you end up with!!!

 

Midwest Dually ... I think you misread my post.

When I did the test this morning, the hubs were NOT locked in. I left them unlocked on purpose to see if it was something in the driveline.

pjwoolw ... if it was u-joints, wouldn't I still hear something (maybe not as loud) with the hubs unlocked, but transfer case engaged?

t-case and front diff fluid were both changed a year and a half ago. I didn't do it, so I don't know what the condition was.

Bearings all looked great. I didn't see any kind of anomalies in the grease.

 

Thats what "disengaged" means.

 

X2 on what Chris suggests. Since your noise is at higher speed u joint would be my first thought. Check the front driveshaft u joints also. I'm presuming were talking about a D50 front axle.

 

hey bud, how are your ball joints??? sounds just like what my truck was doing and last year, and it was a ball joint and u joint in front end. jack it up and see if you have side to side play

 

I just had tires put on a month ago. I bought them at Tires Plus. If there was something wrong with the ball joints, they would have pointed it out. The store here absolutely LOVES to point out stuff that *could* be wrong.

Midwest ... the hubs WERE disengaged when I ran in 4HI this morning. If I had an issue with Ball Joints or U-joints, wouldn't I hear something still .. even if not as loud?

 

no even though transfer case is spining shaft to the front end if hubs are not looked in the frontend shafts wont turn, and if it makes noise loked in i would say it a u joint outer prob or could be the inner, do you have stock front end ttb???

 

yes, it is the stock front end (as far as I know).

 

With an open diffferential, with the transfer case in gear and the hubs unlocked, if one of the U joints has a problem, that shaft stops turning and the other one turns twice as fast.

With the front hubs locked, both axles turn if the wheels are turning.

If you think about how the hubs work, the axle is turning in the hub when thay are unlocked.
When they are locked, tha axle turns with the hub.

If the hubs were fubar, when you repacked the wheel bearings you would have seen evedence.

I just replaced one of my automatic hubs right before Christmas.
When I pulled the hubs out to get to the wheel bearings, the grease looked like Never Sieze.
Silver paste.

The Warn hubs are about 165 a set for the Dana 50/60 axle.

 

Thank you Dave for the explination!

See, this is what I am wondering about... is it the differential, or the transfer case? Thats where I have narrowed it down to by the sounds of things. I was hoping that by removing the front drive line entirely, that a different result would occurr, hopefully pinpoint things down a little more s to which it would be!

Just as Dave pointed out with the hub grease, checking the fluids in the differential and transfer case will hopefully provide more results!

 

Midwest ... based on the explanations above, if it was something with the differential or transfer case, I should have heard the noise even though the hubs were disengaged (I didn't hear anything with the hubs disengaged) ... or am I reading something wrong?

Given that I did not hear the noise while the hubs were disengaged, it leads to most likely u-joints or hub? If it was the hub, I should have noticed something when I repacked the bearings.

My garage is pretty small (and VERY wet due to snow melt). I'll check the u-joints tonight. If they're bad, what should I look for?

 

I would turn one hub in, the rotate the driveshaft by hand.

The axle with the hub turned to free should turn when you turn the drive shaft.

Next, reverse the free and locked hub and repeat turning the drive shaft.

If you don't run 4x4 very often, it is possible for a U joint to freeze up, even though the joint don't look bad.

If the U joint bearings are going out, you will notice the cross don't sit in the cap centered like the others are.
Also if you turn the drive shaft back and forth, there should be no play in any of the U joint cap to cross locations.

With a 50, you have three joints in the axles (one drivers side and two passenger side)and two in the driveshaft that could each be the source of your noise.