HELP 1900 RPM sound!!!!!

[rices]

Hay yall,
I have a 2001 2 wheel drive Cummins with about 76,000 miles on it with a 4" exhaust and no other upgrades. My problem is when i haul a Travel trailer, Cattle Trailer, anything under load when I hit 1900 RPM Hwy speed there is a loud rumble ( vibration sound) within the cab. It is deafening, but there is no vibration in the steering wheel. This started happening after the transmission was rebuilt 2 years ago. I have taken it to 4 different mechanics, even back to the Transmission shop. They hear the sound but they have not been able to identify what the problem is. I have had the drive train rebalanced, replaced all fluids including rear-end fluid. had bolts tighten, this is crazy and no one knows what it is? Help please, I don't know what to do!

Honor and Respect

 

[AEdelheit]

Sounds like exhaust drone, was anything with the exhaust changed when the transmission was done??

 

[rices]

AEdelheit,
Yes, I had the 4" installed after the sound came, and the noise remained the same. It was the same pitch and vibration with no change.

 

[Timd32]

We just went thru this in the 12v section, no clue what they finally did to.fix it, I think we got it down to a possible cracked exhaust manifold or a exhaust issue.

But some other things, bent valve, bent pushrod, turbo surge, lift pump, boot clamps.

Here are a few links to read up on possibly maybe something will help you out.

https://www.turbodieselregister.com/threads/143494-Bent-valve?p=1347093#post1347093

https://www.turbodieselregister.com/threads/61802-turbo-bark-surge?p=558256#post558256


This is a 12v post.
https://www.turbodieselregister.com/threads/175455-sounds-like-a-helicopter!-bad

 

[rices]

Thank you so much! I will look over these!

 

[docbubba1]

hey i have an 01 and after new mbrp exhaust install on saturday, vibration and resonance bad from 1500-2100 worse under load. spin up in nuetral sounds and feels fine.
contacted mbrp also. any thoughts on why exhuast would resonate and vibrate like that over stock?