Engine Brake Hissing Sound

[Jack Marcus]

Have a 2007 1/2 Dodge 3500 Dully w/ 400,000 miles. Since about 250,000 miles I get a hissing sound while engine brake is on and I lift off accelerator. Does not happen if engine brake is off. It hurts my ears!!

Also when engine is cold if brake is on it makes noise till engine warms up. Again, turn off the brake and the sound goes away.

Possible gasket problem???

 

[Hoefler]

No problem, totally normal. It is the exhaust that is escaping around the butterfly when it is closed. If you have straight pipe or a flow through muffler, it will be more noticeable.

 

[Bob V]

Sounds like you have a exhaust leek, check the band clamp between the turbo and exhaust brake. Might also be before the turbo but you should be able to hear it while accelerating

 

[Bob4x4]

07. 5 should be a 6. 7... ... ... . not a stand alone e brake, get a stethascope and probe around while the noise is present

 

[Prairie Dog]

I've never heard a 6. 7 but if the EB is engaged, isn't all that exhaust still trying to escape through a tiny opening in the turbo and won't it still make a hissing nose?

 

[DE Jeeper]

i would guess a small exhaust leak. i bet the turbo to manifold gasket it cracked. was happening often with my set up until i want with copper gaskets.



aaron