How important is the exhaust brake?
I'm a flatlander from the gulf coast. I've only been out west once but I loved it and want to go back. I've looked at several smaller class c or class b+ rigs. Some are gas and some are diesel. Found ...
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An exhaust brake is not needed with a gas engine.
Diesels use exhaust brakes, because diesels don't have good engine braking by nature. This is due to the fact that the intake air plenum of a diesel is always open. There's no throttle butterfly that closes off the intake on a diesel, like there is on a gas engine.
On a gas engine, all you need to have good engine braking is adequately low ratio gearing in the axle, and use the lower gears in the transmission to control the vehicle's speed on downgrades.
If you have an automatic tranny, you need one that stays locked in each gear, particularly the lower gears, rather than one that freewheels, disconnecting the engine from the axle when decelerating.
This was a major pet peave of mine with the Ford E4OD auto tranny in my 7.3 diesel F350. The tranny would freewheel, removing what little engine braking the diesel could provide. The truck was a nightmare to go down long steep grades with a heavy trailer.
I had the tranny completely rebuilt, modified and reprogrammed, to provide maximum engine braking, in all gears at, all times. That was a major improvement in safety. I also had the engine's computer reprogrammed, to close the turbo valve whenever the throttle was let off, to act as a sort of exhaust brake.
On my 5.8 gas engine F350, once I changed the axle gearing from 3.55 to 4.56, with the C6 auto tranny, I had all the engine braking I needed, to not have to use the brakes to maintain speed down most grades while loaded heavy and pulling a trailer too. No need for an exhaust brake with the gas engine.
Gearing is your friend. The lower, the better. :)
Diesels use exhaust brakes, because diesels don't have good engine braking by nature. This is due to the fact that the intake air plenum of a diesel is always open. There's no throttle butterfly that closes off the intake on a diesel, like there is on a gas engine.
On a gas engine, all you need to have good engine braking is adequately low ratio gearing in the axle, and use the lower gears in the transmission to control the vehicle's speed on downgrades.
If you have an automatic tranny, you need one that stays locked in each gear, particularly the lower gears, rather than one that freewheels, disconnecting the engine from the axle when decelerating.
This was a major pet peave of mine with the Ford E4OD auto tranny in my 7.3 diesel F350. The tranny would freewheel, removing what little engine braking the diesel could provide. The truck was a nightmare to go down long steep grades with a heavy trailer.
I had the tranny completely rebuilt, modified and reprogrammed, to provide maximum engine braking, in all gears at, all times. That was a major improvement in safety. I also had the engine's computer reprogrammed, to close the turbo valve whenever the throttle was let off, to act as a sort of exhaust brake.
On my 5.8 gas engine F350, once I changed the axle gearing from 3.55 to 4.56, with the C6 auto tranny, I had all the engine braking I needed, to not have to use the brakes to maintain speed down most grades while loaded heavy and pulling a trailer too. No need for an exhaust brake with the gas engine.
Gearing is your friend. The lower, the better. :)
