Rattle from Back End

This has been driving me insane for months now. A few weeks back I noticed I had a broken leaf and thought for sure that was the cause of the noise, but I replaced both leaf packs and it's still there. Basically, it sounds like a hollow rattle if that makes sense. I hear it most in bumpy parking lots. If I'm going faster, it needs to be a really bumpy road for it to be loud enough to hear over wind and road noise. If I use the brakes, it disappears. Doesn't have to be enough to actually slow the truck down. It really doesn't take much pressure on the pedal to make the noise stop.

So, I pulled the rear drums off and cleaned everything and inspected them. Everything looks good as far as shoes and springs go. Probably unrelated, but I did discover they were way out of adjustment and the emergency brake cable was tightened too much to compensate. So, I backed off the emergency brake adjustment and tightened the drums with the reverse + emergency brake trick many times. I think they're much better now and my brake pedal feels better/grabs a little higher.

But, I still have the noise. Any ideas what it could be coming from? Any chance it's the emergency brake cables? I'm not sure how much they're typically supposed to move in the brackets connected to the leaf springs.

 

Inner rear fender wells or loose bed

 

Those were some of the first things I checked, along with the spare tire, rear shocks, u-bolts and shackles, etc. Everything is solid and/or torqued to spec. Also doesn't explain why braking makes it stop.

Even if I use a half inch of the brake pedal and keep my foot on the gas to maintain speed, the noise goes away with any brake application.

 

exhaust pipe hanger broken somewhere?

 

or pipe touching the frame somewhere...

 

Your possative it's coming from the rear? Could it be front brake dust shield or spring clips.

Edit; my parking brake cable doest move so that could be a possibility. zip tie it to the clamp and see if that helps

 

I've shook everything and nothing rattles or is hanging low. Crawled under too and didn't see anything like that. Also checked all the heat shields and none rattle.

Pretty confident. And I actually did the front calipers recently because they were sticking. Used new spring clips and the dust shield wasn't rubbing. Also heard the noise before and after I did that job.

 

Good to know. I'll try that. I wasn't sure how much it should move in the clamp and if I wiggle them by hand they do make noise. I'm not positive it's the same noise, but it's the only thing that's remotely close so far.

 

spare tire loose?

 

Nope. Even went so far as to put a small piece of rubber between the spare wheel and the bracket that holds it up to isolate any possible vibrating noise. No change.

 

I'll go with a shoe being loose, even though you've looked things over.

The backing/ebrake stuff isn't meant to do a full on adjustment. Doing the adjustment manually with the star adjuster is much more accurate.

Did you validate that the star adjusters work freely for their full thread? Worth pulling/cleaning/lubing, prior to manual adjusting, if not.

Just get it till the drum won't turn by hand, then slightly loosen till it will.

At the worst you spent some time and have guaranteed working adjusters.

 

I'd like a rattle in my back end. -R Simmons

Oh, wrong forum.

 

That's what I keep coming back to, because of it stopping when I hit the brakes. So, if a set of shoes wasn't tight they have potential to make that noise?

I have not made sure they spin for their full thread length. If it's not the emergency brake cable (just zip-tied both), I'll pull the drums off again tomorrow and make sure of all that. I cleaned them up good and re-applied brake lube to any metal on metal parts, but only tightened them until I heard a slight amount of rubbing on each side then tried to auto-adjust them the rest of the way.

I guess the Toyota way is to get the wheels to lock, then back them off 15 clicks. But backing them off and accurately counting how much through the little access cover behind the drum is a huge pain.

 

Certainly possible, although I've never had the issue. It's free to double check since you can DIY.

Sounds practical.

They may be free, or they may bind on just the couple of threads you need to move them through. It's why I suggest just making sure they work smooth all the way, both ways. Again, free, practical maintenance.

I like to do it with the wheel on for the leverage of spinning the drum easier. Take it just a bit further than 'first noise', until it won't easily rotate. Back off slowly until it turns easy, no noise. That should be really close.

I agree. Never did any drum like that, was taught by a fairly seasoned mechanic back when that was the only brakes the common man had. I suppose the Toyota procedure may cause a 'full movement' of the shoes into position, but I really can't imagine how that's needed? Could be an engineers on paper perfection, vs engineers that actually get their hands dirty? (best engineers I ever worked with were all DIY types. The textbook boys were always more of a challenge)

 

Awesome, thanks for the feedback.

I can do disc brakes in my sleep, but I never deal with drums so I'm not as confident with what is right and what isn't as far as adjustment goes.

Seems like it has to be something brake related. If it's not those emergency brake cables, I'll dig into this again and see what happens.

 

fuel door? Mine rattles (think the hinge is broke).

 

Axle wrap? GoPro if you got it.

 

Open and close one of your rear doors pretty hard. Do this with both rear doors. Do you get the rattle then?

 

For what it's worth, Had the same issue on my previous vehicle - turned out to be a bad drum brake with loose parts floating around.

 

I almost don't want to post this, because it was my own dumb mistake!

It wasn't the back of the truck at all. It sounded like it because of how the sound traveled, but I started to realize that it happened when the front passenger side wheel would hit a bump. When I changed front calipers a month or so ago, I didn't torque the passenger side to spec, just snugged them with a ratchet quick and forgot to go back around with the torque wrench. They were about 1/3 turn from 91 ft lbs., so the entire caliper could rattle very slightly.

I did have a leaf spring noise that was surprisingly similar from my broken leaf before I replaced the packs. Turns out it was two separate noises from the same side of the vehicle.

I'm not unhappy that I spent time on the drums because at least now I know the adjustment is right (or very close to right) and they're clean. I discovered if I try to go up any more clicks they rub significantly, so I think they are right where they need to be.