[RaiderNation7]

So I noticed the other day while driving I get a very strange noise from my truck when I accelerate really hard. I don't know how to describe the sound...its kind of a grinding noise I guess. It actually sounds more like the normal engine noise but its noticeably louder and a higher pitch. Once the rpm's drop its back to normal and only does this when I accelerate hard. I don't know if this is normal or what it could be if its not. I have the truck fully deleted with EFI. Could it be a timing issue with a tune maybe? Any help at all would be great

 

[Warferox-Veritas]

Is it kinda like driving over rumble strips on the edge of a road?

paging-transengineer-my-wits-end

 

[cyauch]

Automatic or manual?

When i tow 5er i have to watch how hard i mash the skinny pedal. To hard, and my transmissions shudders / vibrates, especially when i have the MM set on performance. I normally start from stops in stock or tow, then bump up to performance when i get to cruising speed on the interstate.

 

[RaiderNation7]

Its an automatic. And this has been happening with no load. Empty.

And I wouldnt say its exactly like driving over rumble strips. U dont feel any shake or vibration either. Its kind of a growl almost. To me it kinda sounds like when you go to shift and miss a gear on a standard. It just grinds I guess. Thats the closest thing I can get to but its a faster growl than missing a gear

 

[RescueRam]

Don't know much about autos and every case and problem is different but we have a 99 3500 cab and chassis, auto, truck is stock, reg cab with 12' dump flat. growled and made a shutter noise loaded or unload. stand on it hard and it shuttered the truck at take off and just made a shutter sound after moving. Finally had enough of it, took it in and the drum was blown apart and gouged the inside of the case all to crap but still ran some how.

 

[BIG_RED53]

My manual 6.7 makes a similar sound with the minimaxx. I believe it is injector cackle because it seems to go with rail pressure and I've noticed some medium duty ISC's do it also (with big huge voith automatic transmissions)

 

[nevadajones]

If it's coming from the motor I'd say it's injectors. Does it really rattle when you first get into it? Stock injectors on a hot tune have to work pretty hard. My truck does it even worth 100hp injectors. Play with your timing. Back it off one setting and see if it calms down. But as far as I know its normal.