P500 Nasty growl or "rocks in a box" noise on hard braking - HALP

[lukebuz]

Hello! First post - and glad I found this forum! Going to buy a rubber noise mat (if not too late from Trigger).

Anyways, hoping you can help a bit. I have a 2017 P500, about 500 miles on it. Had it since new, and it's had a fairly easy life, with just a little firewood hauling now and then.

The problem that just occurred is a really nasty growling/clunking/rocks in a box type rattle when braking quickly. Good example is I have a 1/4 mile drive to the mailbox, and I'll be going 25-30 mph, 5th gear. If I stop normally, it growls and makes a little noise. If I stop quickly (enthusiastic driving) it goes from a little noise to the much louder concerning noise I'm now hearing.

It's a new noise - just started a few days ago. I did the 75w-140 front and rear oil changes suggested here. While super easy, it didn't change anything.

Along with oil change, i've also verified there is nothing blocking the rotor or caliper (it's clear), and I've also washed off the dirt and grime (just in case) and also no different.

Can anyone help? Ideas to check?

 

[CID]

Have a closer look at your brake pads, sounds like at least one pad is gone and you're metal to metal. Shouldn't be at 500 miles but you never know.

 

[DG Rider]

Check the pads and for rocks or whatever stuck in the pads, but it's probably normal. 500 and 700 have very similar rear diffs, and this noise is common in the 700. 500 also does it, but not nearly as bad.

 

[lukebuz]

Thanks, both. I'll take a much closer inspection with a mirror to the caliper and pads, and see what I can see. I'll update shortly.

DG - I'll also be doing your oil change cut-out. Thanks for passing on good tips!

 

[lukebuz]

Well, can't see jack in the rear - going to have a pull the caliper, and looks to be a PITA. Will do it in the next day or so. Will pull front wheels, looks to be easy just to see what I see...but I'd expect them to be fine. I will post back after I take a peek.

I totally get the the noisy diff - mine is noisy too, but this is redonkulus if from the rear end...

 

[DG Rider]

Starting at about 32 seconds...

 

[SWB]

Check make sure you do not have water in rear end too. Sound like it needs pads.

 

[CID]

Starting at about 32 seconds...

Dude, you need to edit yer sig line, git onnit. 🙃

 

[DG Rider]

Dude, you need to edit yer sig line, git onnit. 🙃

Not sure what you mean?

 

[CID]

Not sure what you mean?

Your sig(nature line) says Present: 2015 Pioneer 500, Past: 2014 Pioneer 700-4, needs an addition, doesn't it? 🤔

 

[KYhillbilly]

mine will do it from time to time mainly in 4wd and going down hill quickly and hitting brakes. I pulled all pads and replaced them even though they were in good shape. I mainly just gear down so i never investigated further.

 

[trigger]

Doubt you're going to find a problem, they all do it.

 

[lukebuz]

KYhillbilly - Did you have any change after swapping your brake pads? I'm not fond of wasting time and bloodying knuckles for no reason...
But, this is strange. It's a new noise - never did it for the previous 2+ years, and then it just started. So strange.

Also, add another KY member. I'm down in BG, KY.

 

[DG Rider]

Your sig(nature line) says Present: 2015 Pioneer 500, Past: 2014 Pioneer 700-4, needs an addition, doesn't it? 🤔

Ah...ok. These days I'm 95% on the phone, and in vertical mode the Sig's don't show. So I forget about them.

 

[CID]

Ah...ok. These days I'm 95% on the phone, and in vertical mode the Sig's don't show. So I forget about them.

U kids and yer mobile devices.

 

[DG Rider]

U kids and yer mobile devices.

I'm 46.
1.5 years ago I would have said no way, but the convenience of it is hard to overlook.

 

[100Acre]

Starting at about 32 seconds...

Mine started making this noise too. I've already changed the pads in the front but not the rear.

 

[JimmyA]

Mine make the same noise going down grades! Could be the way the gears are cut in the rear diff? I'm living with it.

 

[DG Rider]

Mine make the same noise going down grades! Could be the way the gears are cut in the rear diff? I'm living with it.

Mine started making this noise too. I've already changed the pads in the front but not the rear.

It's "gear lash". A consequence of having the rear brake on the drive shaft. A slip and grip cycle that resonates in the tiny bits of slop in the components. Sounds like unwashed ass, but is completely normal.

 

[NTCPrezJB]

Sounds like unwashed ass

That's descriptive and hysterical! Thanks for the laugh sir.