100 series vibration after letting off on the gas at 55mph plus

[ColoradoCarlisle]

Did a search and founds tons on vibrations but not on this

Just towed a 3000 pound camper from Denver to Moab and back Did a little wheeling and now when I'm going down the road and let off the gas it hums and vibrates at 55 plus

Crawled under and noticed that in front of the rear diff there seems to be new oil I have not noticed before

Vibration seems to be coming from the rear

What inside would be causing this
Piñon gears usually whine correct

Thanks

 

[skhochay]

Did a search and founds tons on vibrations but not on this

Just towed a 3000 pound camper from Denver to Moab and back Did a little wheeling and now when I'm going down the road and let off the gas it hums and vibrates at 55 plus

Crawled under and noticed that in front of the rear diff there seems to be new oil I have not noticed before

Vibration seems to be coming from the rear

What inside would be causing this
Piñon gears usually whine correct

Thanks View attachment 1054442View attachment 1054442 View attachment 1054443

possible time to change it - no lifts on the rig? if so ho is the cardan angle?

 

[ColoradoCarlisle]

Thanks
Change What?

No lift
That's was coming Thursday

 

[bwell]

From what little info, I'm going to say your pinion bearing looks like it would be shot, which could explain why your seeing the new leak, which appears to be the pinion seal going out due to the bearing failure. Similar sounds when I had bearing failure on a Tacoma in the past, but no vibes. Pinion bearing failure could explain the slight vibration once you let off gas. I wouldn't drive it tell you can diagnose it further.
Put rear axle on jack stands and try to isolate any movement up and down or lateral if you grab the drive shaft where it enters the rear diff. If you can move it up/down or side to side at all I think that would be your sign. Or put whole truck up and check your u-joints while under their, that could be possibility as well. So many possibilities. Good luck

 

[GregLCA]

You might want to do a quick check of your rear fluid level....

If it was a simple leaking seal, and you've lost enough fluid you can certainly get a lot more gear noise... and if that pinion is starved for oil you will eventually burn up that bearing.

Checking fluid and topping it off is a cheap thing to check first. No matter what though it looks like you should replace that front pinion seal.


-G

 

[PADDO]

Did a search and founds tons on vibrations but not on this

Just towed a 3000 pound camper from Denver to Moab and back Did a little wheeling and now when I'm going down the road and let off the gas it hums and vibrates at 55 plus

Crawled under and noticed that in front of the rear diff there seems to be new oil I have not noticed before

Vibration seems to be coming from the rear

What inside would be causing this
Piñon gears usually whine correct

Thanks View attachment 1054442View attachment 1054442 View attachment 1054443

That uni looks kinda dry, I'd give all six drive train grease points a hit and see if that helps smooth things out. FWIW I grease my drive train two or three times a year. Also check your diff breather isn't obstructed, any pressure build up there will force oil past seals and that could be contributing to the pinion seal leak. Any chance you damaged your drive shaft or lost a weight while off road?