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How do I turn up the Jake brake?
- Thread starter Rockmad
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Nope its on or Off. I assume the truck and transmission are working as expected and its just not enough braking power. Also the higher the RPM the more braking power will be avaiable. I use a pac brake which according to marketing has the most avaiable braking power on the market. I also have a manual so I can really get the RPM up where it works the best, I tow almost at 26K total and love it.
I have the BD brake. Works great with the 6 speed.
Sure did help going down into Skagway, AK last fall with 28,680 lbs
according to the scales at the BC Yukon border!
I did need to learn to use it though. Lots of rpm the better it works.
Sure did help going down into Skagway, AK last fall with 28,680 lbs
according to the scales at the BC Yukon border!
I did need to learn to use it though. Lots of rpm the better it works.
I would be willing to bet the fire truck has an electric/hydraulic unit this is INSIDE the engine and mechanically holds exhaust valves open to make a controlled stall. The switch lets you pick how many cylinders are involved. Your Dodge cummins has a butterfly style flap in the exhaust that blocks exhaust flow to add back pressure. Two completely different systems(I think)
Dave
Dave
Two completely different systems(I think)
Dave
Your right Dave, Two completely different systems.
Dave
Your right Dave, Two completely different systems.
You need to check the back pressure that the jacobs brake holding... I'm guessing that there is a leak and your not getting full retarding HP... . Take it back to your installer and have them put a test gauge on the truck and drive it... they should see 55-60 psi of back pressure at 3000 rpm when they snap the throttle off and the butterfly comes closed... This system is very straight forward... if your installer doesn't have a test gauge... . he needs to get one to correctly test these systems... .
If they can't achieve that back pressure they have some problem... . most likely a leak. . or the valve isn't coming 100% closed...
Hope this helps... BTW any additional back pressure than the 60 psi and you might push open an exhaust valve and it could strike a piston and do damage... .
Also remember on those brakes that connect to the ecm have a short delay... this delay is to allow the fuel pressure in the fuel rail to drop to idle conditions before the brake comes on... .
You should be able to tow 15-18K lbs of trailer weight and go down a 6% grade and not have to use your service brakes to hold the load... .
If they can't achieve that back pressure they have some problem... . most likely a leak. . or the valve isn't coming 100% closed...
Hope this helps... BTW any additional back pressure than the 60 psi and you might push open an exhaust valve and it could strike a piston and do damage... .
Also remember on those brakes that connect to the ecm have a short delay... this delay is to allow the fuel pressure in the fuel rail to drop to idle conditions before the brake comes on... .
You should be able to tow 15-18K lbs of trailer weight and go down a 6% grade and not have to use your service brakes to hold the load... .
Last edited:
chazj said:PK: I also have a BD Exhaust Brake (vacumn controlled) on my 02 Ram 6 sp. HOWEVER... as soon as I step on the accelerator the EB Disengages. It works Very Well BUT, after reading your post, I wonder what I am doing wrong to make it work even better???.....
Not sure what you mean? Mine works great!
Just like advertised. I did install it per the instructions including checking
the vacuum and adjusting the little box.
The EB is sappose to disengage when you step on the gas.
Mine works great, just works better at higher rpms like it should.
Even empty mine will slow me down alot. I use it all the time in town
except when it's wet or icy out.
Also really helps warm the engine up! I'll sit at a stop light and flip it on
while I wait.
BUT! I don't use it on the cold morning when the high idle kicks in.
I don't like it running at 1100 or so degrees with out me watching it.
The "Jake Brake" is NOT the same as an Engine Brake. Totally different.
The "Jake Brake" is mechanical and works the valves in the engine.
Ours is just a butterfly valve that closes and compresses the air.
Higher rpms the more air it can compress = more stopping power.
I do know if my BD ever goes out I will order another BD the same day!
PKozlowski said:
Mine has never gone above 600* (pre) with the exh. brake on and engine idling at 1000rpm. It shouldn't got anywheres near 1100*. High idle and EB is the best (quickest) way to warm up. Just for fun, on really cold mornings I'll put the T-case in N and trans in 3rd and warm that up too.
BD brakes are supposed to keep a relatively constant backpressure, at least on the air operated brakes. Mine will pull 40K right down to nothin' in 2nd gear from 2000rpm down... I don't like kickin' it in any sooner, I don't need to slide my tires.
:-laf Ok, slight exaggeration, but you get the idea.PK: I must be more "brain dead" than usual...
Somehow I got in my mind that you "stepped on the gas" to increase the RPM's and subsequent performance of your EB. That's where my confusion came from... as any slight pressure on the pedal disengages the EB.
My EB works exactly as you describe. As an added bonus it saves on my service brakes... . 116,000 on them an approximately 80-90 % pad left...
Somehow I got in my mind that you "stepped on the gas" to increase the RPM's and subsequent performance of your EB. That's where my confusion came from... as any slight pressure on the pedal disengages the EB.
My EB works exactly as you describe. As an added bonus it saves on my service brakes... . 116,000 on them an approximately 80-90 % pad left...
The dealer that I got the truck from installed it. They are 750 miles from here so I can't take it back. I have had trouble towing my bobcat and going down a hill. 6% and I have to use the service brakes.
I know that a Jake brake is the engine brake normaly, but I have a Jake Brake brand exhaust brake on the outlet of the turbo. I am not happy with the auto, but my wife drives it most with our 10 month old. She did not like the 6 spd I had in the last dodge. Can the dealer check this? I chose the Jake because it did not void my warranty.
I know that a Jake brake is the engine brake normaly, but I have a Jake Brake brand exhaust brake on the outlet of the turbo. I am not happy with the auto, but my wife drives it most with our 10 month old. She did not like the 6 spd I had in the last dodge. Can the dealer check this? I chose the Jake because it did not void my warranty.
Are you shifting down to 2nd coming down the hill? That would raise the RPM and increase braking power.
Dan
Dan
Chazj, Woo. I thought I was loosing my mine! So we're on the same page now.
Maybe it is just the difference in brands. BD has the most braking power of other brands and alot more braking at lower rpms. I found that info on the web somwhere before I purchased mine, that is what sold me on the BD. It had almost double the braking power at lower rpms!
Cattletrk, Mine is doing the 3 cylinder idle at 1200 rpms on a -35 deg morning and if I pull on the EB
it will go right up. Mine is Pre turbo also. It actually goes up quick! I should video it some morning and post it. I don't think anything is wrong with it, it's dumping a bunch of fuel in there just to stay running.
We drove up to Anchorage from Cheyenne in Sept. Some big hills, 6 and 8deg or more.
Never had any problem going down them.
The one going to Skagway was steep and windy. Put it in 3rd and put the EB on and
went down the hill. It took 37 minutes in 3rd get to get back up the hill!
Holy cow that was a big hill! LOL!!! Pulling the 30ft 5th wheel and the 20 foot
Big Tex atv trailer with two 800 pound atvs on it, plus all the other crap like generators
bla bla bla. I was WAY HEAVY!!
Maybe it is just the difference in brands. BD has the most braking power of other brands and alot more braking at lower rpms. I found that info on the web somwhere before I purchased mine, that is what sold me on the BD. It had almost double the braking power at lower rpms!
Cattletrk, Mine is doing the 3 cylinder idle at 1200 rpms on a -35 deg morning and if I pull on the EB
it will go right up. Mine is Pre turbo also. It actually goes up quick! I should video it some morning and post it. I don't think anything is wrong with it, it's dumping a bunch of fuel in there just to stay running.
We drove up to Anchorage from Cheyenne in Sept. Some big hills, 6 and 8deg or more.
Never had any problem going down them.
The one going to Skagway was steep and windy. Put it in 3rd and put the EB on and
went down the hill. It took 37 minutes in 3rd get to get back up the hill!
Holy cow that was a big hill! LOL!!! Pulling the 30ft 5th wheel and the 20 foot
Big Tex atv trailer with two 800 pound atvs on it, plus all the other crap like generators
bla bla bla. I was WAY HEAVY!!
There are several miss nomers mentioned above... .
1 - on cold engine starts and warm up... all the exhaust brake does is back up some of the engine heat... . there is no way any of you on idle or fast idle could see the 1100* mentioned above... there just isn't that much heat produced from the engine at that time... . Are you sure you don't mean 1100 rpm for fast idle and not 100* F.
2 - if any of you have a either the pacbrake or jacobs unit and can't hold a 15,000 lb trailer down a 6% grade you have a problem... . remember that jacobs had some problems with leaks 18 months or so ago and stopped installing for a while... . on a long down hill after you've just crested a hill and the exhaust is RED hot you need to know there are no exhaust leaks... . the excessive heat after a long grade leaking into the engine compartment on a slow down hill will cause problems... . remember this heat is not being generated by the retarding HP but from the latent heat left over after the hill climb. .
3 - if you look at the retarding HP chart on the PRXB PacBrake I think you'll find it retards better than the other brands listed... as well as functions to a lower RPM, just compare the carts on the respective web sights...
4 - we often pull a trailer that is 20-22K lbs... but the exhaust brake won't hold it 100% down a 6% grade... the best we've been able to control down a 6% grade of 6 or 8 miles is about 15-18K lbs of trailer weight with our 04, 04. 5, 05 duallys w/6speeds in the lower gears... . the 04 currently has 230K miles with its first brake job at 160K miles... .
5 - heat is a by product of combustion and there isn't a large amount of heat generated during retarding... ... so you won't see extra heat in your EGT or water temperature... what you can see is heat soak after pulling a long hill and now slowing down..... temperatures will rise until the pipes cool down and the cooling system catches up..... after all there is a slower rpm engine running and less air through the cooling system just after cresting a long grade... .
One last comment... there is a lot of hype on some of these web pages... but the jest of this is a good mechanical engineer will tell you... that if you have the same back pressure and the same RPM, in like trucks you will receive the same retarding HP..... what some brake's do is hold that back pressure to much lower RPM's making them more efficient and functional..... because as we all know you can't hold the engine at 2800 going all the way down that hill... .
We've been doing this for 30 years... first as one of the largest Jacobs dist in the Pacific Northwest..... but now we offer the PacBrake units..... since PacBrake started... we just think they have a little better idea and aren't such huge corporation to deal with... . their just nice guys who know a lot.....
OK... I'll get off the soap box. . hope this helped... .
Jim
1 - on cold engine starts and warm up... all the exhaust brake does is back up some of the engine heat... . there is no way any of you on idle or fast idle could see the 1100* mentioned above... there just isn't that much heat produced from the engine at that time... . Are you sure you don't mean 1100 rpm for fast idle and not 100* F.
2 - if any of you have a either the pacbrake or jacobs unit and can't hold a 15,000 lb trailer down a 6% grade you have a problem... . remember that jacobs had some problems with leaks 18 months or so ago and stopped installing for a while... . on a long down hill after you've just crested a hill and the exhaust is RED hot you need to know there are no exhaust leaks... . the excessive heat after a long grade leaking into the engine compartment on a slow down hill will cause problems... . remember this heat is not being generated by the retarding HP but from the latent heat left over after the hill climb. .
3 - if you look at the retarding HP chart on the PRXB PacBrake I think you'll find it retards better than the other brands listed... as well as functions to a lower RPM, just compare the carts on the respective web sights...
4 - we often pull a trailer that is 20-22K lbs... but the exhaust brake won't hold it 100% down a 6% grade... the best we've been able to control down a 6% grade of 6 or 8 miles is about 15-18K lbs of trailer weight with our 04, 04. 5, 05 duallys w/6speeds in the lower gears... . the 04 currently has 230K miles with its first brake job at 160K miles... .
5 - heat is a by product of combustion and there isn't a large amount of heat generated during retarding... ... so you won't see extra heat in your EGT or water temperature... what you can see is heat soak after pulling a long hill and now slowing down..... temperatures will rise until the pipes cool down and the cooling system catches up..... after all there is a slower rpm engine running and less air through the cooling system just after cresting a long grade... .
One last comment... there is a lot of hype on some of these web pages... but the jest of this is a good mechanical engineer will tell you... that if you have the same back pressure and the same RPM, in like trucks you will receive the same retarding HP..... what some brake's do is hold that back pressure to much lower RPM's making them more efficient and functional..... because as we all know you can't hold the engine at 2800 going all the way down that hill... .
We've been doing this for 30 years... first as one of the largest Jacobs dist in the Pacific Northwest..... but now we offer the PacBrake units..... since PacBrake started... we just think they have a little better idea and aren't such huge corporation to deal with... . their just nice guys who know a lot.....
OK... I'll get off the soap box. . hope this helped... .
Jim
I had a Jacob's exhaust brake installed by the dealer when I bought the truck new. After putting on a new turbo and exhaust system, I had the opportunity to see how the brake functioned. I'm not sure if the brakes come preset, or are supposed to be set by the installer, but the butterfly was not closing all the way. The butterfly has several holes drilled in it (I assume to keep back pressure from getting too high), so I felt fairly confident about adjusting it to close more fully. There is a threaded rod and locknut that this is accomplished by, and is very straight forward. It can be done easily with the inner fender removed on the passenger side.
After adjusting mine, I noticed greatly increased braking. I don't make a practice of it, but if you're slowing down with the exaust brake engaged, and downshift quickly into 3rd gear (about 40 mph, rpm jumps to ~3000) it will break the back tires loose and bark them pretty good. Maybe your's needs adjusting too? May see different results with the auto though...
After adjusting mine, I noticed greatly increased braking. I don't make a practice of it, but if you're slowing down with the exaust brake engaged, and downshift quickly into 3rd gear (about 40 mph, rpm jumps to ~3000) it will break the back tires loose and bark them pretty good. Maybe your's needs adjusting too? May see different results with the auto though...
Darren, it sounds like your brake is working as it should but without convertor lockup it is not going to slow you much. Check that your TC is locking. I know that with my Banks brake it will come on certain times without TC lock and it sounds like it is working but really is just making noise until the lockup kicks in, then I really feel the braking.
With the '06 and the Jake, the lockdown should be happening seamlessly UNLESS the dealer didn't set it up right.
Since it was dealer installed, have them check it out. Put the ball into their court. Ask them to pressure test and test drive with you so you are both on the same track.
The brake is a real help but on severe downgrades with a big load you still will need some help from your service brakes. Shifting down to keep RPM up helps a lot. My RV isn't as big as some but at over 11K, it still puts the e-brake to work but holds speed down pretty well. It won't be as effective as the engine brake on your fire truck though.
Dan
ps. Use that Tow Haul/OD Off button too.
Since it was dealer installed, have them check it out. Put the ball into their court. Ask them to pressure test and test drive with you so you are both on the same track.
The brake is a real help but on severe downgrades with a big load you still will need some help from your service brakes. Shifting down to keep RPM up helps a lot. My RV isn't as big as some but at over 11K, it still puts the e-brake to work but holds speed down pretty well. It won't be as effective as the engine brake on your fire truck though.
Dan
ps. Use that Tow Haul/OD Off button too.
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