Pulsing vibration (not needle bearing)

I get this pulsing vibration sound and feel on the floorboard and steering wheel from about 25/30mph to highway speeds (where it’s the loudest). Does it in 2wd and 4wd, no difference. All diff fluids serviced regularly, new wheel bearings all around, greased drive shafts, ECGS bushing. Sound was there before all parts replaced above and still there now. It’s on a OME 2” strut lift, diff drop, spidertrax spacers and 275/70r17 Hankook Dynapro ATM with about 30-40k miles on them (still lots of tread left and just starting to show signs of age/weather cracks on the sidewalls. Maybe taken on a few dirt roads here and there but never really utilized the 4x4. I called ECGS and they don’t think my front diff is bad. What’s my next move? We just ordered some all season Goodyears so I can eliminate the possibility of it being the AT road noise and I guess being proactive with potential issues with the cracking on the tires. Leaves me with front diff passenger bearing being shot or cv axles being bad/worn? Thanks

 

My guess is tires, front tires because you can feel it in the steering wheel. AT tires arent necessarily loud just because they’re AT…but some models are worse than others, or you just get a bad tire. If you’re able and willing, you could try swapping the fronts to the back.

Have you inspected the treads all the way around? Did one of the tires pick up a tar snake or other debris?

A long shot might be something related to the lack of 4wd use. I have a theory the front slip yoke on the driveshaft can get sticky just like the rear driveshaft slip yoke. Except the front driveshaft on your isnt engaged very frequently…which might lead to the whole slip yoke seizing up to some degree (that’s me guessing). Maybe you could try finding a straight road and driving in 4hi for a while, and also 4lo on some straight side streets. The torque in 4lo really gets that slip yoke moving. Again just a guess, but worth a try. The manual recommends about 10miles a month in 4wd if I recall.

 

I’m really hoping it’s the tires. I will try to get down there this next week and inspect each tire thoroughly, CV joints and driveshafts again. Just before rebalancing the tires I rotated them to see if noise traveled, no luck. (Leads me to believe it isn’t the tires but really hopeful)
I appreciate some input, I’ll keep y’all posted.

 

Is the frequency of pulsing increase linearly with speed?

 

The pulsing sound/vibration increases with speed.

 

I get the needle bearing vibration at around 40-50 mph that comes and goes - feel in in the front left tire

 

Have you found out the problem? I have installed a 3in lift kit and since then I have felt this pulsing vibration from front left . Same as you describe

 

Does yours go away when you put it in 4H?

 

Although I was in denial because my tires physically looked fine and had tons of tread life left….. turns out it was the tires. I wanted to go back to square 1 even if it meant factory suspension, removing wheel spacers etc. I put on factory tires and poof! Gone! Thanks everyone!

 

It actually does go away when I put it in H4

 

That's the diff bearing.

 

Right on. I can’t seem to find any videos on changing the diff bearing. Is that something I can replace or would it be a full diff replacement(hope not)

 

There are probably better ones than this, but it's still useful.

https://www.youtube.com/watch?v=nllcwqI1YVI

 

ECGS has a video on their website.