coolant leak rear of engine no idea where...

[Airfrm]

I have a 2008 6.7L cummins, I have two issues but not sure of they are related. The coolant issue, Im loosing coolant from the rear of the engine. The top of the bell housing is wet, but Im not loosing a lot of coolant, but enough to make some steam come up from the hood when I stop, but I traveled over 200 miles pulling a trailer and its only a little low on coolant. I just bought a pressure tester but before I test it, is there anything in the back that might be problematic that I can start looking at? The second issue Im having, when I run the engine brake, I get a squealing noise, but if I turn the brake off, it stops. Also no issue when its idling or under power and I have no power loss. Im thinking maybe an air leak of some sort but these two issues started about the same time so not sure if they might be related.

 

[Mikey-KE7LBB]

EGR cooler, turbo flange, or exhaust manifold gasket is the source of the squeal. Most likely the gasket between the EGR cooler and manifold. As far as coolant leaking, it could be from the EGR cooler, or the plug on the back of the block. Hopefully it's something simple like a fitting.

Easiest way to find the exhaust leak is to look for soot. If it hasn't been leaking long enough to leave any, run the truck with the hood shut and shine a flashlight from the bottom. The best time to do so, would be on a cold start when the engine is cool enough for the EB to engage. You'll be able to see it right away.

 

[Airfrm]

EGR cooler, turbo flange, or exhaust manifold gasket is the source of the squeal. Most likely the gasket between the EGR cooler and manifold. As far as coolant leaking, it could be from the EGR cooler, or the plug on the back of the block. Hopefully it's something simple like a fitting.

Easiest way to find the exhaust leak is to look for soot. If it hasn't been leaking long enough to leave any, run the truck with the hood shut and shine a flashlight from the bottom. The best time to do so, would be on a cold start when the engine is cool enough for the EB to engage. You'll be able to see it right away.

Well I found my coolant leak, it was the top heater hose elbow. Now just have to find the pesky squeal

 

[SHobbs]

One of the med units in my department had a squeal or whistling noise like you described, turned out to be the exhaust manifold gasket.