That could depend which retarter system your talking about.

Engine Brake (jake brake): Mounts to valve train to turn engine into air compressor. (Opens exhaust valve just before TDC of compression stroke)
Having larger displacement I do believe would create better braking over a smaller engine.

Exhaust brake: uses a sliding gate or valve to cause a restriction in the exhaust system after the turbocharger.
Larger displacement would be better here also, if the restriction is the same on both motors.

Hydraulic Retarter: Use a device similiar to a torque converter, using engine oil as a resistance in the retarding device. Caterpillar Brakesaver

Driveline Brake: Uses the force of electromagnets as a resistance on the driveline of the vehicle. Usually used on large mining vehicles.

 

If you use your head, gears and engine brake,going down hills is not that difficult. You need to maintain control at all times.

 

Crossing the Rockies.....dang I thought you were talking I-80 windy Wyoming or better yet I-90 (which has been a crap shoot) where it's snowy, packed snow & ice for so long I wouldn't know how to act anymore.

 

I dont see what the big fuss is, I use my gears to adjust my speed through the hills, nothing to it... I dont care if I have to go 1st wit it...

 

I'm so glad you classified East Coast mountains as hills cause that is what they are.....the thread was talking the Rockies as in Mountains.

Everyone is afraid of Donner until you do it once and then wonder what the big deal was.....not a big deal follow the signs.

 

Hmmm maybe the west coast has more dramatic mountains in height like 11,000 - 14000 feet but Ahhhh actually in terms of grade -- West Virgina, Tennessee, North Carolina and Pennsylvania have some nice grades like 12% - 22%. The back roads of Maine, Vermont, and New Hampshire (and all there is -- is back roads) have some very nice grades much more steep than say a long 6% grade of Donner. Add to that ice as opposed to packed snow and you have a great combination for an incident.

Do not be fooled .... :wink:

 

Crackaces......don't worry about me been behind the wheel for over 30 years.

Been on roads that probably can't classify them as roads. Don't stop for much, wheels turnin' me and the company are makin' money.

 

There are not any REAL mountains east of Denver. You flatlanders got it easy.