Sorry for so many questions but it can be hard to determine exaclty what you are dealing with without actually seeing/driving the truck with the limitations of the internet.
You have referred to this as a noise AND a vibration, do you physically "feel" a vibration or do you only hear something? Does this sound like a droan noise perhaps?
droning type noise/vibration felt in floor board drivers side and gas pedal. When 4x4 engaged seems to go away or smooths out. as long as gas pedal is depressed(applying torque to system) is when it occurs. back off the gas, smooths out. Checked the u-joints and lubed, no changes. Guessing either wheell bearings or front shafts. Totota says they find nothing, but where they drove it was never on highway to get real occurence of problem. Gets annoying after a while driving at the prolonged speeds 45-70, worst seem right between 60-70 mph
Thank you for your patience, I have 3 files I have uploaded for you that I would like you to review to get a better understanding here:
So right now you are probably trying to figure out what the first 2 have to do with you right?
I am factory certified with experience with toyota and lexus dealers.
The gx470 is the same powertrain as your sequoia and I will be completely honest with you that the engineers tweak and perfect the Lexus line much more then the Toyota line. A front end droan is a known issue on GX and Sequioa, this is just to show that the front end noise CAN be resolved but does not apply to the toyota axle. Read download 3 and see if this applies to you.
Do they have same procedures listed for the Sequoia then also? Or just give these to the dealer service dept??
I need to take these to the dealer then for service ASAP and should be covered under warranty as I alreaady had it in twice at 45,500 for the issues.
Download #3 is the only one that directly applies to your truck, I supplied download 1 and 2 to give you a better understanding of what's going on here. You mentioned what you read on the forums.....take those posts "with a grain of salt", if you produce a million units then some will have issues, just because someone had gears or a bearing replaced does not mean the exact same thing is wrong with your truck. See if you can get anywhere with download 3, if this does not resolve then they need to put a set of chasis ears on the front differential to trace the noise to either a wheel bearing, differential preload bearing or differential assembly.
I hope this has been of some help to you. Thanks!