When did you first notice this?
Any recent work done?
Has this vehicle been sitting for a long time?
Can you feel any vibration or thump in the steering wheel while this happens?
Does pressing the brakes have any effect?
Any pulsing in the brake pedal while applying brakes?
I agree with others that it sounds like something at axle speed, not driveshaft speed.
- No recent work, but a ton of brake work in early 2020. Pretty much the entire brake system, front and back, was replaced.
- Has not been sitting for a long time, though it's been driven a lot less in 2020 than in previous years. Still, it has not gone more than 4 days without being driven somewhere except for a couple of weeks in March 2020.
- I've been driving very differently, though. Three weeks ago I started commuting to a workshop I've been loaned for my interior rebuild; I don't have a garage and it's cold here, so I needed interior space. That has led to driving approximately 3 hours a day round trip for the past couple of weeks. This is very different than the past, where I'm typically driving maybe 20 miles in a day, or else driving hundreds of miles a day, on a longer trip. I have never "commuted" in the bus before. I also have never driven it completely empty, and it is very bouncy empty (everything is out for an interior rebuild). I have been on some extremely bad, torn up roads, at highway speeds in a big empty box (welcome to winter in New England). In one of the videos where the noise is happening you can see a lot of bounce (this one had the best sound but you can't see the front of the bus in the shot).
- Different elements of it were noticed at different times. I have noticed an occasional sort of a "bang" or "pop" that seems like it's coming from under the driver's side, but very sporadically, for a few months. I first had a significant issue after I went to a truck scale a few weeks ago, and could not seem to pull off of it. I just couldn't move forward. Granted, I was on a slab of ice, but I drive on ice all the time. I eventually just gave it A LOT more gas than I should have had to, and got moving. It didn't feel like a transmission issue, but something was off. It wasn't just the ice. Later that day I started experiencing a pretty big shimmy in the front end, which I chalked up to needing an alignment until the crazy noise started. If you look the bus from the front, the wheels do not look aligned.
- I first heard the noise when I was slowing to a stop, with brakes. I assumed it was a brake issue right off the bat, like a stuck caliper, but in my experience that smells really strongly of burning brakes, and it doesn't quite behave like a stuck caliper. For example, it's very random when it's going to happen. Plus, the caliper looked great.
- Yes, big vibration in the steering wheel, however, NOT with the noise. Separately.
- As far as pressing the brakes goes... I don't think the brakes themselves have any effect on the noise but it generally begins when I and deccelerating so it's hard to say for sure.
- No pulsing in the pedal, though the firmness of the brakes does not always feel the same.
Thank you for digging in on this!