What are these "retarders" and how do

Very close Jack. Actually the intake and exhaust valves close simultaneously, duplicating the compression stroke on all cylinders.
Of course the exhaust valves must be cracked open ever so slightly to prevent blowing a head gasket, thus the noise, which is not actually engine exhaust per se, but merely compressed air escaping.

 

Actually, there is an emotional/physical parallel there.
Sounds mechanically Freudian, but I see where you're going.

 

That was not my intent, I was merely trying to bolster your theory, thereby making it look like we are both smart.
Be advised I have no psychiactric training, but I've been watching "House".

 

My engine is really quiet with that soot filter on so I don't worry about it so much.

 

Oh yeah, hows that working out? Don't have one yet, but had to watch a training video.
Have you had to do that regeneration thing?

 

my 07 freight shaker you can't even hear when I use the jakes (on high or low). I know when I hit major cities if i know that traffic is going to be touch and go I can reach that switch really quickly to get some extra braking power. I try to be aware of circumstances so I don't need it, but then you boys and girls know better than me how unpredictable those lil 4 wheelers can be.