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Discussion Starter #1
I see there are a few entering the market and I am interested in hearing what your experiences are. I like the idea of using the engine horse power to aid in slowing the vehicle and the benifits that go along with it (reduced trailer brake maintenance, quicker engine warmup, etc).:rockin
 

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I have used and installed several on customers trucks, but no Dmax's. I will tell you, they work EXCELLENT! BD or Pack is the way to go. BD's kits tend to be a bit cleaner. If you pull, man thats the only way to go.
 

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Well, most of my heavy haul customers are running Dodges (easy now - I forgot my flame retardant suit!:D ) and all of them swear by exhaust brakes. I had one on my 2003 Cummins and it was a night and day difference. Towing in hills is so much safer and easier. It really is the best thing a hauler can do to his truck.
 

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i thought the chevy has grade braking.or maybe engine/tranny braking. example. when i am pulling my toyhauler at a good rate of speed or going down a grade, when i step the brake my rpm's move up alittle and i think my engine and tranny start helping me slow down. ( poss down shifting ) ??
this is not the same as exhaust braking ?????????
 

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Discussion Starter #7
What I'm refering to is a manually controled butterfly valve that restricts exhaust flow. I've done some checking and here is what I've found; Long story short - this will produce momentary higher cylinder pressure (just like having a "potato" in the tail pipe). This increase in turning (crankshaft) force will turn the engine into a vehicle brake (I have been told as much as 40 horse power worth of effective breaking). Grade braking works in a similar manner except that it is computer controled. The computer senses vehicle and engine speed conditions and will produce braking by automatically down shifting when speeds increase by a given percentage. It also modifies the fuel and shift timing to aid in this. The effect is similar to the exhaust valve except that it does not have the added benifit of the controlable exhaust restriction - plus you don't get the additional sound (only if it sounded like a real Jake Brake). There is an additional benifit of quicker engine warmups in cold weather.
 

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Can you explain a little more on how the jake brake helps the engine to warm up on COLD days?
 

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I'm not sure about the true explaination as to how this will help with engine warm up (I got caught repeating product advertisment). If I had to guess, I would say that it uses the valve to restrict exhaust flow at idle which will force the engine to work harder to reach and maintain this set RPM. I'm sure somebody out there can set us straight on this.
 

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BY engaging the brake while idling it raises the EGts about 150*, thuse help ing the motor to warm up faster.

Grade holding or grade braking is simply transmission programming to hold a gear instead of unlocking the converter and letting you coast. However, due to the nature of how a diesel runs, it does not produce a large amount of Engine braking by it's self. By using an exhaust brake to close off the exhaust flow and apply back pressure against the pistons (usually about 60 PSI) you can greatly improve braking and safety.
 

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Discussion Starter #11
Thanks for the info.
 

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Once an e-brake is installed, how does the driver activate it? I assume there is some sort of button/switch close at hand that activates the system. Also, I will be towing our new Rockwood 33' TT, about 7500# loaded. Would you recommned an E-brake for this?
 

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There are 2 different ways of activating the brake, either a shifter mounted or dash mounted switch. This switch will arm the system. When you lift off the throttle the brake will engage in about 3-4 seconds, to keep from being jerky. If you step back on the throttle the brake will disengage.

Anyone towing in the hills will benefit from an Exhaust Brake.
 

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No. The Brake is set to produce back pressure against the motor, but not near enough to float the exhaust valves. You aren't applying any more pressure to the motor than you do with normal driving. With turbocharged motors, you have whats called drive pressure, which is the pressure built up between the piston and the turbo wheel. This is what turns the turbo over. Every turbo has an A/R ratio, which tells you the ration of drive pressure to boost pressure. In the interest of turbo spool up and lack of smoke, most of your stock chargers are around a 2:1 due to smaller exhaust housings and wheels. So, at 30psi of boost, you make 60psi of drive pressure against the pistons. All you are doing is applying the same amount of pressure against the motor without building all that power.
 

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So, at 30psi of boost, you make 60psi of drive pressure against the pistons. All you are doing is applying the same amount of pressure against the motor without building all that power.
All 2nd gen and higher dmax's have an exhaust brake from the factory: the Variable Vane Turbo. Mine is configured with EFILive such that I always have an exhaust brake at the higher non-fueled RPM's. Given that this custom tune also provides 90 towing HP, mpg benefit, lower noise, better altitude performance, nicer progressive power when empty than handhelds provide, accurate DIC, EGR defeat, wheel size speedo calibration, just to scratch the surface. a great tool.
 

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The Allison FAQ page answers the question of using an exhaust brake on the D/A combo: http://www.allisontransmission.com/service/faq/index.jsp?CategoryID=11 In short, the Ebrake must be connected to the TCM.
Frozenhosehead- a true Jake brake willl not work to warm up an engine, because it works by altering valve timing, which effectively turns a diesel engine into an air compressor working in reverse. What this discussion is about is an exhaust brake- a restriction in the exhaust system.
 

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i thought the chevy has grade braking.or maybe engine/tranny braking. example. when i am pulling my toyhauler at a good rate of speed or going down a grade, when i step the brake my rpm's move up alittle and i think my engine and tranny start helping me slow down. ( poss down shifting ) ??
this is not the same as exhaust braking ?????????
This is not quite the same. Your transmission is using higher rpms and shifting down to slow the vehicle an exhaust (jake) brake uses back pressure in the exhaust. Ever hear a semi let off the gas and the exhaust roars, thats the jake brake.

I have used the allisons engine grade braking towing in the mountains and it works great. If there isn't enough speed reduction from the grade braking just tap the minus button on the shifter to drop another gear. This seemed to be sufficient enough and there was no need for a jake brake. I also drive a semi and every big rig driver knows you don't use the jake brake when it is snowy or icy unless you want the trailer to pass you up. In this case you shift down to create more rpms and there is also a johnny brake on semis. It is essentially a trailer brake. This will help slow you down and keep everything in a straight line. In snowy, icy conditions and if your towing a jake brake is trouble. Any other time ,unless your hauling more than these pickups are rated to tow, the engine grade braking is suffient. If you have to tow that much weight you can buy a good used semi for half of what a new diesel pickup costs.
 
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