Clunk sound in rear when braking?

Can't find any threads on it, but just before I stop, second or 2
before, there's a clunk that sounds like it's coming from the rear,
any ideas?

 

I know it's been discussed, but I can't seem to find where... mine does it too, and I can't figure out what it is.... it seems worse the harder i stop

 

Check your U bolts on the axle and make sure they're tight.

 

fuk! they sure as hell 'should be' I just had the tsb done that replaced
both leaf packs. Had the same clunk prior to that as well.

 

These noises come from a lot of places. Another one is the cab mount and sometimes radiator mounts. One member found his right rear cab mount making noise, and some have found front cab mounts failed.
Those sounds transmit throughout the chassis and will drive one insane. I'd take it to the dealer and let them deal with it.

 

It's before you stop? Different than the coming to a stop and then a couple seconds later...thud?

Does it happen everytime?

 

a second or so before I'm fully stopped...clunk!

I can't be certain it's every time, I usually keep the sub
up pretty thumpy so I miss it.

 

Have the same problem, I heard from another member on here that Toyota is working on Rev2 for the transmission update and that should fix the problem

 

hope so. whatever it is, it can't be good. I just emailed my service manager to see
what he knows about it.

 

Good luck, hope your service manager is squared away....I would be curious the hear his take on it

 

My dealer couldn't replicate it. I've been dealing for it with almost 29k miles. That downshift clunk is harsh at times. I've tried different things and no luck. I think it has something to do with the rpms

 

And for what it's worth, different shocks/ubolts didn't affect mine either

 

I'll post whatever he says here.

He's been good in the past, replaced the leafs & steering damper under the last TSB
for the hard vibe when braking. Turned out the drums were warped as well and
the next day he replaced both as well, smooth as silk since then. This is all I'm
currently dealing with but I expected some things being that's it's a new design.

 

Mine does this sometimes, my dealer said it is the transmission shifting into 1st gear and is unfortunately expected from this tranny and Toyota knows about it. May be related to the updated a previous member posted.

 

I had wondered if it was the new tranny just down shifting and 'designed that way'.

 

Yup experiencing the same thing as mentioned. If I come to a more aggressive stop, meaning my truck has to down shift into first more suddenly than normal there is about an 80% chance you will feel and hear the clunk as it down shifts into first. I am pretty certain it's not ubolts or anything to do with something shifting around because it's loose, it seems the transmission is creating this noise. I took it into my dealership and had the salesman that sold me the truck come listen, he confirmed it. Of course when the mechanics tried they couldn't replicate but simply told me oh it's not doing any harm because of this plate and that plate.....to be honest hurt or not a 40k truck shouldn't have some random ass downshift noises coming from this new tranny! So I am curious to what you others find as I am hoping for an answer soon to prevent any further long term damage.

 

agreed and same here regarding the u-bolts being my leafs were both swapped out for the TSB
and it did this prior as well. Not sure what it is but it sure as hell shouldn't be doing it on
brand new trucks.

 

My 2017 is only a week old and I've already heard it once. I've previously owned a 2002 and then a 2005 Sequoia (both bought new) and both of them did it too. I think it's a Toyota thing, and it always seemed to me with the Sequoias that it was related to the transmission downshifting.

 

Weird...never heard it in the 3 other tacos I've owned; last one was a 2011 4x4 TRD.

 

If it is downshifting related to the drivetrain I can confirm, having a manual transmission, that the drivetrain has what feels like some extra slop to it. You have to be real perfect on shifts to get a smooth, non clunky/clanky shift (which of course you have no control over with the auto).