Can someone help with this noise?

RedAlert · Jun 25, 2015

Here's a question for you hemi experts. For a while now my truck makes this rattle noise when under load for example going up a really steep hill under moderate throttle. Sounds kind of like a small pebble being shaken in a soda can lightly. Seems to happen around 2500 rpms and will go away if I get on it more or let off of it. No driveability issues at all. I tend to forget about it because you can't hear it with the windows up at all. Checked for loose heat shields and all seems tight. Could it be spark knock? I figured the timing would cut back if it was that. Only 11k miles so I cant imagine it being a manifold leak yet

Update: removed the heat shields over the weekend and filled it up with Sunoco ultra 94. Still making the noise. Narrowing it down as much as I can, it only does it when the truck is completely hot(driving for 30+ minutes) and it's under load (large uphill run). Happens as soon as it downshifts and lasts until it upshifts one gear or I put it to the floor. I'm almost leaning towards either a idler pulley or tensioner causing it do to the sudden increase of engine speed. Neither pulley has a any roughness and only marginal bearing play.

Burla · Jun 25, 2015

A dude just had a manifold leak with a new truck, known weak spot. Anyhow, with so few miles why not take it to the dealer? Bumper to Bumper the first 36.

MyOhFive · Jun 25, 2015

it's possible you're hearing the truck labour in 4cyl mode before it kicks to 8.

kg93 · Jun 25, 2015

i wouldn't exactly say thats a sound associated with mds. Just take it in, see if a service guy will go on a ride with you so you can duplicate it

RedAlert · Jul 17, 2015

OK a little update. I've been paying more attention to the noise lately and it seems to only happen after the trans has reached 125+. I can sometimes hear it at 120, but never under that. Was at the dealer for 5 hours today. They couldn't find squat with it. Came back with a clean bill of health. They drove it, checked everything, drove it some more and can't find anything. The tech said he thought he heard it once, but can't pin it down to anything in particular. So I'm still at a loss as to what it could be. I can't find anything loose, out of place and no rattle whatsoever and I've checked everything. It has to be internal to the trans or motor

ExpressRules · Jul 17, 2015

Are you sure it is not engine knocking under load?

Kap1 · Jul 19, 2015

Hi, I had similar issue that you're describing on my 1500. When I was doing moderate acceleration up the hill or freeway ramp, I hard sort of buzzing sound coming from the back window, I have a camper shell, so all sounds amplify through the back window...

After couple trips and back fourth with dealer, they couldn't find anything as they weren't able to reproduce the noise...

Then, they asked me to test drive with their foreman tech, and of course I know how to make this noise happen again... So I did and made him hearhear it

after another day of diagnosing, they found that one of the metal cables under the truck was loose and was vibrating during acceleration and after tightening it the noise stopped

Dusty · Jul 19, 2015

As noted by others, I would first suspect a broken exhaust manifold bolt or nut. Easy to check for. Just check for one missing (they usually rattle out very soon after breaking off).

Check the (black) hard plastic windshield washer line as it comes up from the top of the left front fender and into the underside of the hood. The point at which it enters the hood between the sound insulation is a rattle point. I used a small piece of foam to isolate from the hood.

Check the area near the left side of the firewall in proximity of the lower steering shaft near the engine. There a small electrical harness, a larger black rubber hose covered cable, and an electrical cable wrapped in silver-colored heat wrap. These may not be secured and can vibrate against the left inner fender splash shield or other metal parts.

Regards,
Dusty
2014 Ram Big Horn 1500 Quad Cab 2WD, 5.7 Hemi, 8HP70, 3.92 LSD, factory dual exhaust, 20” wheels. Now at: 023183 miles.

Warl · Jul 19, 2015

I had a vibration issue with my truck as well sounds like what you described. The problem with mine was when they installed my muffler they didn't weld enough for the pipes and when my truck went into mds mode and was struggling it'd cause heavy vibration and rattle my pipes together. Went back to the muffler shop and described them what I was talking about and bam 10 second fix.

Just something to check.

MADDOG · Jul 19, 2015

My light, pebble in an aluminum can rattle was a heat shield near the cat that was slightly loose and hit the cat as it warmed up and expanded.

QwikKota · Jul 20, 2015

Isn't there a metal tab that rides on a bracket for the exhaust? It's only used during assembly and can rattle after the main part of the exhaust is all bolted together. You can just bend it up.

RedAlert · Jul 20, 2015

QwikKota said:
Isn't there a metal tab that rides on a bracket for the exhaust? It's only used during assembly and can rattle after the main part of the exhaust is all bolted together. You can just bend it up.

Already removed that

badblackram06 · Jul 20, 2015

Maybe the torque converter?

RedAlert · Jul 28, 2015

Update: removed the heat shields over the weekend and filled it up with Sunoco ultra 94. Still making the noise. Narrowing it down as much as I can, it only does it when the truck is completely hot(driving for 30+ minutes) and it's under load (large uphill run). Happens as soon as it downshifts and lasts until it upshifts one gear or I put it to the floor. I'm almost leaning towards either a idler pulley or tensioner causing it do to the sudden increase of engine speed. Neither pulley has a any roughness and only marginal bearing play.

grantmcw · Jul 28, 2015

I had this issue but it went away after putting my aftermarket exhaust on, so I just assumed it was something loose in the factory exhaust.

Can someone help with this noise?

RedAlert

Member

Burla

Senior Member

MyOhFive

Senior Member

kg93

Senior Member

RedAlert

Member

ExpressRules

Senior Member

Kap1

Ex Ram 1500 2013 owner

Dusty

Senior Member

Warl

Senior Member

MADDOG

Out Exploring Arizona

QwikKota

Senior Member

RedAlert

Member

badblackram06

Senior Member

RedAlert

Member

grantmcw

Member

Similar threads

Latest posts

Staff online

Members online

Forum statistics

Share this page