whup, whup, whup noise at 30 mph?
I'm searching for ideas on the cause of an odd rotational, speed specific, noise my 2003 Sequoia is making.

When driving, starting initially at around 25 mph I can hear a faint whup, whup, whup noise down under the chassis that is synchronized to my travel spead. It occurs about 2 times per second. As I speed up to 30 mph, it is the most audible and the noise frequency speeds up as well. By about 35 mph it faids out and is no longer is audible (not certain if that is due to other road noises masking it, or something else). There is no bad vibrations or bumping felt, just the rubbing like noise.

At first, I thought the noise was due to my old worn out Michelin LTX tires (worn down to the warning wear bars). I just put on new Michelins with all new balancing and alignment and I am hearing the same noise. Nuts. I just took the truck back to have the new tires checked and rebalanced and they all checked out fine.

Given it noticeably changes with the speed (from 25 to 35mph), it has to be something that rotates with the vehicle speed. Could it be a drive shaft out of alignment? Transmission mounting bushing? Carrier bearings? {I don't feel any vibrations or shaking in the body or steering wheel}. Differential bearing? Wheel bearing going out? Bad brake pads or rotor? A cat jambed up in the fender well :eek: ? With the new tires, they also checked the brakes and reported about 60% remaining.

I've rolled down hills with the windows down and can't really hear the whup, whup, whup coming from a specific corner of the truck, just generally underneath. I've also put the tranny into neutral while coasting and it has no effect on the noise. As I go around corners, there doesn't seem to be any changes from going through left or right corners.

Hhhhmmm???:confused:

By process of elimination, my notion is it is in the driveline to differential area mechanics. I don't see any lube leaking or loose parts. Any ideas or suggestions to trouble shoot?

Thanks
Kenreau

I have the same problem. Had my dealer check out bearings , trans, and drivetrain. They said it was the wheels, had front end aligned , and wheels balanced. Still have the noise. Did you ever find the source of the noise ?

My 05 has probably the same noise. It happens around 30 and again around 55. Im just assuming its the differential, but im not about to replace it unless it gives me a better reason to. Im wondering if a diff fluid change would even help?

Sent from my LS670 using AutoGuide.com App

I changed my differential fluids , front and rear and no change.

$100 says it goes away if you put it in 4wd!!!
It is your front differential, bad carrier bearing I believe. I'm having mine repaired at the dealership right now for that same problem. After they got the rear driveshaft replaced due to a worn bearing (support bearing I believe) and a major vibration fixed, I started to notice the same thing. When I first mentioned it to the dealer they said the new/remaining vibration was caused by the angle of the cv shafts due to my lift, which I know is horse crap because it does it in 2wd but NOT in 4wd. Figured it had to be front diff or t-case but it felt more like diff. Did some searching and found an old TSB for '07&'08 for the exact symptoms I had and you are describing. I drove into the dealership service bay today and explained what was happening and said I found a TSB about it and the gal knew exactly what I was talking about. She even mentioned that there was a new TSB, presumably for the newer trucks. Glad I got it in with only 300km left on my warranty :)
Do a quick search on here or even google for tundra diff vibration TSB and you'll find it.