19 MPH Whooping Sound RESOLVED!

Hi Everyone,
Newbie here - love the forum!
I bought a 2016 Double Cab TRD O/R last year after careful consideration and primarily due to Toyota's reputation for reliability. I loved the truck for the most part (after the transmission TSB) however I was experiencing a pronounced "whoop-whoop-whoop" sound at and around 19 mph that was not attributable to tires or brakes as it happened accelerating or decelerating or coasting or turning or whatever. The best way I could describe it was that at and around 19 MPH, it sounded like Curly from The Three Stooges was hitching a ride under my truck like Robert DeNiro in Cape Fear. I took it to the dealer at about 2K miles and they tried to isolate the sound, re-align the driveshaft or something along those lines and did not resolve the problem. I waited out the rest of the initial "break-in" period and at around 6K miles I was starting to reconsider my purchase and made another dealer appointment.
To my pleasant somewhat surprise, they reported back that they had consulted with Toyota Engineers on the matter and pinpointed the problem to the Transfer Case. They replaced it on warranty and with that - problem totally solved!
They said there was a bad bearing in the transfer case that was causing the sound. Just wanted to share in case any other Tacoma owners were experiencing the same annoyance.
Also - A question for the knowledgeable... Would a Transfer Case replacement require a Tranny fluid top-off? Just curious after hearing the reports of low fluid from the factory. From what I gather, I have a Mexico-assembled Taco and haven't had confirmation of a Tranny fluid check with the 5K service and forgot to ask the dealer when they replaced the Transfer Case.
Thanks

 

Welcome. Lots of issues with low tranmission fluids but this is the first I've heard of a transfer case replace. Must be a one off, I'm sure it happens. Shouldn't be related, but if 2016, you would want them to check the tranny. Almost all are low by about a quart if yoy have tow package.

 

BigMike saw premature wear in his Tcase at only 8K miles. Bearing associated with the oil pump/slinger in the Tcase.

 

Welcome to TW

 

GeronimoCO, I have the EXACT (at 19-24 mph) same issue with my 2016 Tacoma DblCab 4x4! I've had it in to
Toyota dealerships in Idaho Falls, ID, and Carlsbad, CA and they said they couldn't find the cause,
and/or couldn't hear it. The small mechanic shop in my hometown put a stethascope on drive-
train and they pinpointed the noise in the Transfer Case. Very loud, no doubt about it. But the dealerships wouldn't believe.
The noise drives me nuts. Can you tell me what dealership you had success with? And, who
I can talk to? Many thanks.