Clunk noise after coasting

When I’m coasting from say 50 down to 15ish and then give it just a little bit of throttle to maintain that speed I get a noticeable and audible clunk like a gear is reengaging. It definitely doesn’t feel like the drive shaft but maybe the transmission. Other wise it’s shifts pretty smoothly. Anyone else experience this?

 

Sounds like too much wear in the rear differential. There is some slop between ring and pinion gears. When you coast, the gear mesh moves to one side of the engagement because of the fuel cut and the drag it creates. When you hit the gas, it moves back to the other side of gear engagement. Normally this can be felt if paying close attention, but otherwise unnoticeable . If you have too much clearance there, this can become loud and noticeable. Not saying that is the problem, but is a possibility.

chock the tires and put truck in neutral. Then rotate driveshaft back and forth and listen. Then compare to other truck for normal. Watch the pinion shaft/flange as you do this . If you see any axial movement or side to side slop, the pinion bearing is shot.

 

Mine does act like this. It seems to be the rear axel. Doesn't like slow and go on the highways. Pretty much has been this way since new. I have to baby the throttle to prevent it.

 

Thanks for the input! It doesn’t do it all the time but seems to happen when the rpm’s drop below 1k and coasting right when I tap the accelerator. I will try your advice soon!

 

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Hello, thanks for the help. Long time Toyota owner, first tundra. Iv got a 2019 with 37k miles. Been reading through a ton of forums and couldn’t find quite what I was looking for.

 

You got a video of the sound it makes ? Just curious because I might have the same issue but also my spare tire makes a lot of noise sounds like a cluck as well

 

CLLLLUUUUNK...

 

Not sure you truck has driveline zerks ,my 2016 does but I think they went away in 2018.....if your truck has them pump some grease in the driveline zerks and ujoints. Any dryness in the drivline = vibration and clunks

 

@FabioXc right now I don’t have a video. It’s not really something I can always replicate. I’m thinking it’s slack in the drivetrain. It seems to do it when slowing down (coasting) and rpm’s drop way down when coasting around 15ish mph and right before it down shifts another gear. If I press the gas while it’s in between coasting at a low speed with low rpm’s and before it down shifts is when the clunk happens.

@frichco228 I definitely don’t see any zeros to grease but I read where you can pull the boot off right after the carrier bearing and grease that but you need a new boot, new clamps, and a clamp tool. I’m not sure if I even read that right but that’s what I got out of it.