Thump after releasing brakes?

Any ideas? I am having a unusual slight thump after stopping at intersections, red lights etc. At first I thought I had been lightly bumped from behind. But it seems to now happen at almost every stop. Thought it may be stuck rear brakes, but that doesn’t seem to be the case. A harder, quicker stop creates a bigger thump. Almost as though something is releasing. The 12 year old girl at the dealers service desk knew nothing.

 

I had a similar problem and it was the slip joint on the driveshaft was binding.

Marked where it went on the spline and rear diff. I took it off and greased it heavily and no more clunk.

 

Interesting, I get something like this as well.

I thought it was my brakes too since I started to notice it after I replaced my brake booster with a Tundra unit.
The driveshaft seems like an equally logical culprit now that I’m thinking about it.

 

Check the rear shoes for gear oil contamination

 

This is what I was originally thinking, with the increased pressure from the Tundra booster on the wheel cylinders, maybe they started leaking a bit. They looked okay just getting up underneath and looking the area over but I’ll have to pull the drums now to be sure. I need to check how much meat is left on the shoes anyway. Or rear axle seals because mine are probably originals.

 

A binding spline joint? Seems like quite a bit of pressure building up. Wouldn’t this at some point cause issues with the rear diff or tranny?

 

Is it the same as the "phantom rear ending" when you have the AC on in the summer and you're stopped at a light?

 

Axle wrap in my trucks case. It felt exactly like the truck got lightly rear ended. It would happen 1-5 seconds after stopping at a sign or light. I installed a traction bar and it went away 100% instantly. Eventually there was slop in my home made traction bar shackle and the issue reappeared in a "calmer" state. I replaced the shackle with a heim joint and the issue went away 100% again.

The stock rear springs are designed to give an excellent ride when new and unloaded, like say at a new car dealership.

 

I had the same feeling in my Prerunner Bought new in 2012. I torqued the axle U Bolts to 85 ftlbs and the clunk/bump went away and hasn't returned since.

 

^^^Same here, in fact I have to tighten mine a couple times a year. I might add some lock washers or lock tite.

 

This was the culprit on my 07 4Runner but I didn't have to take it apart. Just took 20 pumps on the zerk before any grease came out.

 

That's too much right? I've read somewhere that the spline zerk should only take 2-3 pumps because excess grease can be bad in that spot.

 

I’m referring to the spline in the middle where the front and rear driveshaft mate. There’s no grease zero there unfortunately.

 

I've always been told the slip joints should be greased until you can see them move.

Didn't realize the Tacomas didn't have fittings there.

 

Same issue on my 2013 TRD Sport since I got it, I noticed its more prevalent during the cold season and fades in the summer which I find strange.

I double checked all my u-joints but none of them are serviceable, is that sometime specific to the TRD Sport?

 

Same here on my 2015 sport. Mine does it maybe every 1 out of 5 stops. Worse sometimes If I brake harder. It did it when I bought the truck stock with 60k on it and it's been the same now at 95k. I even added a 1 inch lift block and still the same. Pretty sure I have a bit of axle wrap too. I get a tiny jiggle sometimes when I take off.

My sport has greaseable fittings on the front and rear driveshafts. I do mine a few times a year. A couple pumps is usually enough.

 

Is it possible it is the AC compressor kicking On?

The A/C runs anytime the defroster is on. Even if the light is on. My truck will thump and jump forward if I don’t have the brakes applies very hard.

 

I don’t believe so, but next time I take it out I’ll test it

 

All fantastic replies so far .
Could be a combination of issues . Axle wrap ....How's the leaf springs ? are they all sagged out ?
Universal joints with grease zerks should be greased at every oil change .
The only way to tell if a universal joint is seized is by removing the driveshaft .
Slip and stub spline on the driveshaft uses a special lubricant .
You can use the stuff made by Ford because Toyota has a contract with Spicer that also make our driveshafts

$19 Ford Genuine Fluid XG-8 PTFE Lubricant - 3 oz.

https://www.amazon.ca/Genuine-Ford-Fluid-XG-8-Lubricant/dp/B000NU77DA/ref=sr_1_1?crid=2G9XLEA9LG2G4&keywords=Xg8+ptfe&qid=1639772902&sprefix=xg8+ptfe,aps,119&sr=8-1

 

I've noticed my truck does this as well. I'll be accelerating down the road and let off the gas when I'm coming to a stop. I'll hear/feel a light "clunk" once I let off the gas and begin cruising with no throttle. Seems to only happen under hard load, and it seems to only happen once or twice before it goes away.

What's odd to me is it only happens when it's cold. Goes away completely once it's warmed up. I've greased my driveline a few times now, but I'm wondering if the previous owner never did it and the grease is still working its way around in the joints.