Hoss

This morning while idling in the parking lot waiting for some friends my exhaust brake engaged while I was just sitting there. I had it turned on in preparation for my drive, but didn't expect to hear it while just sitting there idling. Sounded like a jet getting ready to take off.

Is this normal? What makes it engage while idling in park?

New2Diesel

That is absolutely normal.

I have no idea why but it sure does sound cool!!

409CI

Its a warmup feature on the engine. Will run at idle until the engine reaches a certain temp. They sound like a turbine with no muffler in the exhaust, stock you cant really hear much out the pipe from it.

Hoss

Sweet! Glad to know its normal. And as we've all said, it sounds pretty cool.

Hoss

One more question. Will it do it automatically or only if I have the exhaust brake turned on?

Jim W

The exhaust brake will engage under two different conditions by itself.

The first is if the ambient air temperature is below the factory programmed set point around 32F and at idle, if my memory severs me right. I believe the O&M guide will provide this information.

The second condition if the engine is at idle and has cooled down or has not reached coolant operating temperature the exhaust brake will engage to help warm up the truck faster.

Mine has done this since new I believe this is also explained in the O&M guide also, at least it in my 08 manual it did.
Jim W.

Hoss

That's good information. Thanks.

How can I get my hands on an O&M book? My truck came with an owner's manual but it doesn't really provide the kind of information you're talking about. It's just basic stuff about how to operate the truck's features and a maintenance schedule.

Blake Clark

Call Dodge Customer service and they will send you a book if you request it.