2nd Gen Non-Engine/Transmission Did I ruin differential?

[KRStone]

1996 2500 CTD 4x4 auto trans.

Returned from a trip where I was towing a trailer and using 4x4 some, and on the hwy home, around 50 mph, I began hearing a rhythmic noise, not consistent.

Got it home, checked front diff fluid, and my pinky, though fat, could not find the front axle fluid level through the fill hole.

Added near a quart and it was draining out the hole, filled it up.

went for a drive, and the noise was there after about 10 miles.

what should I check and take pics of to determine the damage?

does the front axle actually have axle bearings or just the unit hub bearings?

thank you for the help, I will follow directions and post pics.

 

[RWherley]

there are no axle bearings other then the hubs, what there are is 2 carrier bearings that support the ring gear and its carrier / differential and 2 pinon bearings that support the pinon gear. there are seals at the back end of the pinon and where the axle shaft enters the axle tube to keep the oil in the diff case. one of those seals is probably leaking and thats where the oil went, and its very possible the lack of oil damaged your bearings. The bad part is even with the diff cover removed you really cant see any of the bearings. what you can do is jack the truck up with the cover off a spin the axle and see if you can hear or feel any rough spots in the bearings.

 

[NIsaacs]

Drive train noise can travel front to back and be hard to pinpoint. Did you check the t-case and rear axle?

Nick

 

[KRStone]

Okay, I will check transfer case and rear diff first, then if nothing is obvious, I will begin working on the front to check the bearing play.

I will post pics, because I have never touched the diff gears before, or axle bearings. I have replaced the unit hub bearings on this truck, and the front axle I joints.

 

[crabman]

On my 98 the front axle cover fill hole has a small flat area just below the fill hole & extends about 1/2". You really have to look & feel with your finger to see/touch it. Do not fill above the bottom of that flat spot or the lube will be forced out past the axle seals.
If the diff. oil did get past the seals there should be some residue on the outer ends of the axle area. Diff. lube has a odor that you will recognize once you smell.
The above posts are good advice. Just take your time & diagnose it correctly.

 

[KRStone]

Thank you for the comment.
There is no visible oil from a quick under truck inspection with flashlight. The center of the diff is covered with what I think is engine oil from the breather hose. Could be from the pinion seal, but no puddles, it must be a slow leak.

I did remove the from driveline propeller shaft a few months ago and had the unjointed professionally replaced and the center ball replaced. It was a reputable shop. I then bolted it back to the yokes. I want to include as much info as possible to help with diagnosing.

 

[JMcCoy]

I would put the cheapest gear oil in to try and figure out where it's leaking from. If noise or leak persists, then move forward.

 

[Joe Mc]

Take the front prop shaft out, since you recently had work done. Not saying shop messed it up, just saying its a simple job to help eliminate possibility. Another possibility, is the front diff 4X4 really disengaging? the slide/coupler could be stuck on engaged??? Keep us posted. good luck.

 

[KRStone]

Okay, had to get another set of jack stands.

All four off the ground.

Tried to check Xfer case, I need a different sized Txx than I have to loosen the top fill bolt.

Front wheels have some noise due to the disk brakes dragging, but they don't rock or feel gritty.

I put the xfer case in neutral and checked the drivelines, the rear two piece driveline has a slight bit of knock in the sleeve coupling right near the center bearing. Rear driveline has never been worked on in this truck.

I shook and spun the rear wheels. While spinning there is a faint click, rhythmic, like someone cocking a nicely worked over revolver over and over, smooth and quiet but noticeable. Clicked in relation to the speed I spun a rear wheel. So, when I spin one rear wheel, it is moving both rear axles, the diff gears, rear bearings, pinion bearing, rear driveline and it's unjoints and center bearing and sleeve coupler.

How do I isolate the rear, or is that click something normal like the rear diff abs sensor clicking on the tone wheel (or whatever it has in the rear diff)?

 

[JMcCoy]

I would pull the rear drive shaft to isolate the rear. There should not be any noise coming from the speed sensor. Also pull the rear wheels and drums to make sure it isn't brake related.

 

[KRStone]

I will. The rear drums make a swoosh when the drag a bit, but the clicking is definite. I have time today to work on it.

 

[KRStone]

Oh man, got heat exhaustion last friday, two fridays ago, then the flu hit me.

Finally went outside this morn.

Wanted to spin each rear tire independently and see if i could isolate the wheel the ticking is coming from.

Noticed the passenger rear tire has a very unusual wear pattern. The outside edge is melting off sideways. This may be attributed to the current problem i am having.

Anyone ever seen this before?

 

[B.G. Smith]

Looks to me like the tread is separating from the tire. If that is the case and it comes off at highway speed you might be looking for a rt. rear quarter panel.

 

[JMcCoy]

Looks to me like the tread is separating from the tire. If that is the case and it comes off at highway speed you might be looking for a rt. rear quarter panel.

X2. Looks like new tires are in order. May not be cheap, but at least it's an easy fix.

 

[KRStone]

Its the top 1/8 inch, maybe a bit more

 

[NIsaacs]

Check your rear axle alignment, that tire looks like it is scrubbing.

Nick

 

[KRStone]

Check your rear axle alignment, that tire looks like it is scrubbing.

Nick

Would a worn rear axle bearing cause it to be out of alighment? It wouldnt be the whole axle because of the bearing, just the passenger side shaft?

 

[Joe Mc]

Don't think so. When NIsaacs suggested checking rear axel (Differential/Housing) alignment I think he's dead on. That tire seems to be scrubbing = skidding as you go down the road, does the inside of the other tire look the same? You could do a quick measurement from inside of the front of the leaf spring to the edge of the housing and compare both sides. This won't be very accurate but if it's off a little that's enough to do it.