Bad front differential?

For the last few days I’ve been dealing with this - about 800 miles of this, 200 of which with a camp trailer.





On my way home last night (well, early this morning) I started hearing a buzzing noise around 40 mph - almost like a playing card in a bicycle tire. It seemed to be coming from behind the dash right below my feet. If I switched off 4wd it ramped down quickly and went away.

I’m thinking a bad differential or maybe driveshaft/u-joint. Any ideas? My drivetrain specialist friend is out sick today and my whole truck looks like this so I’m pulling the wimp card until it thaws… but in the meantime, I’ll take some speculation.

I was in 4wd for about half of those 800 miles, switching out when the road improved. It didn’t improve last night, just got worse.. and worse.. and worse…

 

Ice build up?

 

I wondered that myself. That would be best case..

 

Ooof. Gotta be fun towing in that! As suggested I’d wager is some build up of ice somewhere. Really don’t see diff failures, especially not when being used like this.
Did you try to put it back in 4wd and see if the noise came back?

 

Where are you going in that weather with that trailer? My nightmare towing scenario

 

Does the noise change when you turn in either direction?

 

Ya, it was… fun…. Hahaha.

I was able to reproduce the noise by shifting in and out of 4wd and resuming speed. I didn’t hear it below about 40 mph.

The noise was strange - I’d been on the road for almost two hours and thought I was driving over the rumble strip and had some change or something rattling around in my cup holders. Considering I couldn’t actually see the road for most of the trip and was navigating by snow markers/reflectors, it made sense. But once I tried paying more attention, it was definitely coming from forward of and under my feet. I pulled over at the next pullout (and snapped that pic) to inspect. I didn’t smell anything or see fluid leaking so I soldiered on. Couldn’t really crawl under the truck with making a snow cave..

I had just been plowing through 6–14” of snow on the road; you could hear the trailer busting drifts on either side of tracks.

Long story, but I’ve been working on a job in the middle of nowhere. It saw several delays, keeping me from getting in to do my thing, so I had to camp out on the job for a week - hence the camp trailer. I’ve had to pull in inclement weather similar to that on several occasions, but this was pretty brutal. 4.5 hours to get home, driving faster than most, but not what I consider unsafe.

There was barely a skiff of snow Thursday. Saturday night , a few storms rolled in to all three weather systems I had to traverse and made traveling downright scary in just a few hours. I was planning on coming home Saturday night but wasn’t able to finish up before the roads turned to garbage. So I left the trailer, drove home Sunday afternoon in 50 mph sidewinds that drifted and iced the roads, then went back Monday to finish up. Didn’t get done until midnight, so I made a sammich and napped for 30 minutes. Checked the weather and it was supposed to be worse Tuesday morning, so I hitched up and left around 1am.

I’m no stranger to traveling at night in the middle of nowhere in winter conditions: fewer other travelers, but that has it’s advantages.

Roads weren’t plowed so I was cutting trail for at least 1/4 of the trip. But the roads weren’t totally iced, either, because they hadn’t been packed down.

It was still pretty intense. It kept me WIDE awake.

I didn’t notice it changing when turning either direction. I wondered about a bad CV, but they both turn all the time and the noise went away when I disengaged 4wd. It also seemed to dissipate when I was on power, but that may have just been because it was harder to hear.

Still could be side/needle bearings as @ColoradoTJ suggests. That would make sense.

It was pretty warm (relatively) here today so the roads were wet. It cleaned most of the snow off my truck. I’ll try 4wd again tomorrow and see if it’s still making noise. Really hoping it was ice buildup.

 

And as of yesterday wasn’t fun enough, this happened this evening. After unhitching the camp trailer, I hitched up one of my enclosed trailers and drove around town. 3 miles after dropping that trailer, I was cruising down the road in town at 35 mph and ‘pssstt pssstt pssttt… vwomp vwooomp verromp’

 

Ouch! That's a nice gash...

 

Dude, that bites. I'd just go home and call in for a week. Let the bad juju pass.

 

218k on my 2013.

Believe you me… I am ready to toss my phone in the river and be done for a while.. ha.

 

Also, this would lend credence to the ice buildup theory..



Yes, that’s the spare tire as I dropped it down. First time the truck has ever seen the spare come out and play.

I planned on doing it at some point so that wouldn’t hurt my feelings.

 

Small update: had the truck in 4wd the other day and did not experience any of the same symptoms at the same speeds, so I'm hoping it was due to ice build up. I'll be installing an AWD sequoia case this weekend, so I'll be able to spend a significant amount of time in 4wd to confirm. I'll also be servicing the front diff and will be looking for sparkles or fragments.

 

As part of the sequoia transfer case, do you remove/lock the front axle disconnect?

 

Nope, it remains intact and functional since the sequoia tcase retains 2wd as an option.

 

Another clue… Stoopid sticker…