Raptor rattling riddle - experts wanted

[BajaFred]

Wondering if anyone has seen this or has ideas?

I think it sounds like a spray can rattle and you can feel it in the floorboard, steering wheel isn't shimmying beyond collateral damage from the rattle-induced vibrations

It's slightly different than the other thread as it happens at an exact moment - driving and accelerating "normally" rattles start right by 50mph, goes away IIRC after 53/55mph

If you get on it hard, the rattles don't happen

Can't find another speed band where it happens - tested up to 85mph

Rattling goes away either when you let off gas (rattles stop immediately) or if you keep driving, the rattles get progressively louder then abruptly stop above the speed range

Will not do it in park nor on a lift, which makes troubleshooting painful

IIRC happens in both 2H and 4A

http://www.youtube.com/watch?v=Wf_Kzea2vTA

 

[hamster]

Does it do it no matter what gear you are in?

 

[Bullishone]

No clue. Doesn't sound good though def take it to the dealer.

Sent from my Nexus 6P using Tapatalk

 

[Hockster]

Very hard to diagnosis this from a video. It almost sounds like a loose heat shield. Is the performance the same?

 

[Mark986]

Oil level okay?

 

[BajaFred]

She's at the dealer, didn't make it 50 miles away

They spent 6 hours on it today, nothing obvious is loose, not fluid/tire related

As for gears, it's tricky since if you're accelerating normally, you'll hit the same gear at the same speeds but didn't think of locking out gears one by one

Performance feels fine rattling aside, get on her during the rattle and she moves just as fast out of it, no apparent lag or hesitation

Checked wastegate and looked for any cables or wires that could be smacking the chassis

The head scratcher is how damn consistent it is starts as you near 50mph so feels like a gear or a resonant/harmonics issue

Built a few weeks ago

 

[BajaFred]

Dealer suspects vacuum harness for the front four-wheel drive activation

Usually its the IWE that goes bad, this would be the first time he's seen the harness as the issue

He's very confident so am hoping it's a done deal

 

[mindgame100]

Try getting your hands on this..
Wireless ChassisEAR

Albeit.. I would suspect it is a IWE vacuum problem also..

 

[BajaFred]

Try getting your hands on this..
Wireless ChassisEAR

Albeit.. I would suspect it is a IWE vacuum problem also..

This is exactly what they wired up to the truck today

 

[smurfslayer]

BF, do you have a go pro?

maybe hood mount it or get it somewhere outside to see if you can pick up a rattle outside. This sounds like a cab rattle to me but if you can feel it in the floorboards, and the harmonics match the rattle and it only happens while you’re moving it has to be related to the drive train. If it’s 2h / 4A consistent, I’d be inclined to look from the trans rearward. It almost sounds like a dying cat(alytic converter).

I’d suggest engaging a decent go pro externally to see if you can pick up a rattle with more audio clues. I’ve got one on my ZX10r that picks up a mysterious bodywork rattle on video, that is not in the audio sound track on the bike. It happens about 4-4.5k but I’ll be damned if I can track it down. I can only hear it on the GoPro !

Good luck with it.