Intriguing Little "clunk" Under Commute Braking

I'm not sure if its done this since day one but, I recently noticed a subtle "clunk" while I'm mildly braking the truck in traffic or a stops around town. Hard braking is silent.
At first I thought nothing of it as my STI brakes were noisey as heck and the pads flopped around inside the calipers and always made noise. Especially track pads...squeek city all day.
Then it occurred to me I have drums on this truck.
Its the most subtle little "thump".
I crawled all over under the truck yanking on EVERYTHING. Especially the drive shaft after installing the lift. I went through the leaf packs and checked tightness on all hardware, shocks, etc. Nothing is loose.

Gonna remove the spare tire and all of the other stuff under the back seat tonight. Hoping its something silly. Oh, and I gotta' check for "Wife Debris". We just got back from a road trip and she just drops stuff anywhere in a vehicle. Could be chap stick under the front seat or something...

I just have nightmares about the rear axle doing strange stuff under braking or something in the driveline shifting under braking. I know I am WAY overthinking this...

Do the drum brakes get sloppy after 40K?

 

lol, wife debris. I noticed a similar little thump on my 2023 DCLB after adding a lift and it ended up being the slip yoke on the driveshaft binding a bit under braking. When the axle rolls forward the yoke slides in and out of the transfer case, and if it isn’t greased it will stick and then release with a soft clunk. My mechanic pulled it apart and slapped fresh grease on it. Hopefully it's just wife debris, haha.

 

Now this is the kind of reply I was hoping for! My 23' has the new style drive shaft so no zerk fittings on the driveshaft. And I am due for grease! I may be pulling my shaft this weekend! Thank you!

Note: Been married over thirty years so I am well versed in the pulling of the drive shaft.

 

My 17 has always done this and now with 76k it's more noticeable. Pretty sure it's driveline slop or a lack of grease with the u joints.

 

My mechanic said something about torquing the U-Bolts, so you'll probably want to look up the specs on that

 

If nobody has checked the rear brakes in 40k miles then yes, pull the drums off and take a look. The shoes likely need a clean-and-adjust

 

check the truck bed, might have forgotten to let out the son in law, ex wife, father in law..

 

I find stuff in my bed making a lot of noise with that brake click. Usually it’s a d-ring in my
Bed rail. But then again some random stuff ends up back there.

 

52 ft lbs

https://www.tacomaworld.com/threads...acoma-rear-axle-u-bolts.654617/#post-22801946

 

You sir, are a gentleman. Gracias!

 

if you are without a torque wrench the quick way of checking for tension is to tap the U bolt with a screwdriver, hammer, wrench, even a dowel rod. It should make a ringing noise and all 4 u bolts should have the same tone.
What pitch is the right one? There will be some variation between rigs, best to give it a tap after torquing and keeping a mental note of the sound.
Its become part of my pre-flight and post crawl checks so its done often enough to know when the sound is 'off'

 

I don't trust my ears enough. My Dad was a drag racer growing up. We rode two strokes. I took the muffler off my lawn mower cuz I hate my neighbor. We went to Punk Rock and Heavy Metal shows as kids. (Still do.) I have been building and working around loud machines my entire life. I can't hear my wife across the dinner table at a steak house.

Torque Wrench it is. Thanks though...

 

LMAO it's a truck, with solid axle, on leaf springs. Everything moves an inch or two under braking.

Could be slip yoke telescoping with axle wrap.

Could be carrier bearing shifting in its rubber.

Could be the composite bed bouncing up and down relative to the frame...

 

All true. I still need to get my rear end under there and pull the driveshaft and lube it up. Especially with the mielage on the truck. On my older trucks I've had to get the drive shaft extended after lifting and I was hoping to avoid that. Still, zero shaft play when I yank on it. Nothing like my old trucks where you could physiclaly see movement of the driveshaft after the lifts.

 

Front Brakes are known for Brake Klacking, when the exposed slides get corroded the pads skip across them a little. You can just replace them with new slides without even taking the caliper off and then add in a 2nd anti-rattle spring on each front caliper. This would be the cheapest option to try 1st.

Now if you are feeling it in your seat then I would lube the Slip Yoke as the next step as well. But you have to generally take the drive shaft apart to get to it.

 

Do you have a hitch ball installed (or any other hitch accessory)? Check the play, and grease the receiver as necessary. That probably won't fully fix the issue, but it helps to damp the "thunk" under harder braking.

That's the source of "thunking" in both the wife's and my trucks when braking.

 

Hey thanks man! I am definitley looking at the slip yoke / drive shaft. I had my kid put his ear to the floor and the "clunk" is under the back seat. I'm also feeling "binding", for lack of a better description while braking on certain grades on the highway. Like my rotors are warped but, its in the driveline. So I am, almost, 100% sure it is driveshaft angle, pumpkin angle, and some TLC being needed down there.

 

Hey thanks man! No towing accessories at this time!

 

I recently had a similar experience; I would get a clunk as I came to a gentle low speed stop. This felt like it always happened when the truck would make the final shift into 1st as I was coming to a stop.

Got an ATF fluid change/flush done and it went away. I think they usually tell you to do this at about 60k miles (100k km), so maybe you're a bit early.

 

Appreciate the insight! Thanks!