Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×
RV Trip Planning Discussions

Go Back   iRV2 Forums > iRV2.com COMMUNITY FORUMS > iRV2.com General Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 06-26-2021, 07:37 AM   #1
Epp
Senior Member
 
Join Date: Aug 2020
Posts: 107
What is the difference between a jake brake and an exhaust brake.

I understand the difference between an engine brake and an exhaust brake. What classification does the Jake brake fall into?

On my 2001 Newmar DSDP, spartan chassis Cummins ISC, I have a Jacobs manufactured exhaust brake, downstream of the turbo. Is the Jacobs manufactured exhaust brake a Jake brake, or are the names just coincidentally similar?

The reason this question arose is that under my dash I have three connections for an exhaust brake set up. One connector is labeled “two stage exhaust brake”, second connectors labeled “exhaust brake”, third connector is labeled “Jake brake”. When we purchased this rig, the connector marked exhaust brake is the one that is connected to the switch the other two are unused.

When I looked at my exhaust brake, I noticed it was hey Jacobs brand exhaust brake.

Thanks
Epp
__________________
Thescoutranch
2001 Newmar DSDP/Spartan Chassis/Cummins ISC
Epp is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 06-26-2021, 07:42 AM   #2
Senior Member
 
Join Date: Oct 2014
Posts: 3,920
Trick question.


Jacobs corp makes both exhaust brakes and engine compression brakes.


But, they are well more known for their engine compression brakes and that is what most call to mind when a Jake brake is mentioned.


No possibility of an engine compression brake on an ISC (8.3 liter). The smallest Cummins with an engine compression brake is the ISL (8.9 liter).


Exhaust brakes are either ON or OFF.


Engine compression brakes can be up to 3 stages, 2 more common on RV applications. Basically, how many cylinders are doing the braking.
__________________
Brett Wolfe
Ex: 2003 Alpine 38FDDS. Ex: 1997 Safari Sahara. Ex: 1993 Foretravel U240
wolfe10 is online now   Reply With Quote
Old 06-26-2021, 08:45 AM   #3
Senior Member
 
Join Date: Jul 2014
Posts: 28,998
Exhaust brakes plug the exhaust gas from getting out the manifold. That stops the engine from pumping air.

Engine brake lets the pistons work to compress air, then open the exhaust valve let it out, before it can push the piston back down.

The High/Low, 1,2,3 switch selects How many cylinders are controlled.
twinboat is online now   Reply With Quote
Old 06-26-2021, 10:04 AM   #4
Epp
Senior Member
 
Join Date: Aug 2020
Posts: 107
Great, I appreciate the clarification.
I’m assuming Spartan just put the wiring in there To accommodate just about anything.

I assume that the Jake brake, and the two stage brake is also controlled through the engine specific ECM and TCM.

Thanks
Epp
__________________
Thescoutranch
2001 Newmar DSDP/Spartan Chassis/Cummins ISC
Epp is offline   Reply With Quote
Old 06-26-2021, 12:20 PM   #5
Member
 
SherryeDan's Avatar
 
Join Date: Feb 2019
Posts: 40
Then explain the transmission brake....2000 discovery 5.9 isb w/ Allison 3060
SherryeDan is offline   Reply With Quote
Old 06-26-2021, 12:29 PM   #6
Senior Member
 
Join Date: Oct 2014
Posts: 3,920
Quote:
Originally Posted by SherryeDan View Post
Then explain the transmission brake....2000 discovery 5.9 isb w/ Allison 3060

Allison transmission brakes are available on Allison 3000 and 4000 series transmissions. The model number would end in "R".


VERY effective at braking-- turn momentum into heat in the transmission, so more complex transmission cooling systems are required.


They are found on some high-end coaches. Foretravel, for example has had them on most models starting in 1994. Their newest coaches-- I am not sure.
__________________
Brett Wolfe
Ex: 2003 Alpine 38FDDS. Ex: 1997 Safari Sahara. Ex: 1993 Foretravel U240
wolfe10 is online now   Reply With Quote
Old 06-26-2021, 02:55 PM   #7
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 24,637
A transmission "brake" is technically known as a "retarder" and Allison uses that name (thus the "R" after the tranny model number if so equipped).
__________________
Gary Brinck
Former owner of 2004 American Tradition and several other RVs
Home is in the Ocala Nat'l Forest near Ocala, FL
Gary RVRoamer is offline   Reply With Quote
Old 06-26-2021, 06:13 PM   #8
Senior Member
 
Join Date: Nov 2015
Posts: 18,947
Quote:
Originally Posted by SherryeDan View Post
Then explain the transmission brake....2000 discovery 5.9 isb w/ Allison 3060
Alison Retarder Info
http://www.svfd.net/SVFD%20Files/Art...very%20costly.
__________________
Is it time for YOUR Medication or Mine?
Dodge 3500 w/Tractor Motor & NUWA 5vr
US NAVY---USS Decatur DDG-31
Old-Biscuit is offline   Reply With Quote
Old 06-26-2021, 09:21 PM   #9
Registered User
 
Triple E Owners Club
Ford Super Duty Owner
Join Date: Apr 2013
Posts: 1,745
Quote:
Originally Posted by Gary RVRoamer View Post
A transmission "brake" is technically known as a "retarder" and Allison uses that name (thus the "R" after the tranny model number if so equipped).
Gary there are also retarders on the back end of a transmission not a part of the tranny. They are electric and called a retarder also. A generator type retarder with big windings that use magnetic fields to create resistance. Dynamic Braking!
These are very common on big mobile cranes.

The retarder on the Allison transmission is hydraulic and uses transmission oil. They create a lot of heat which in turn makes tranny oil changes a must at regular intervals.
Ted Lambert is offline   Reply With Quote
Old 06-27-2021, 04:10 PM   #10
NXR
Senior Member
 
NXR's Avatar
 
Join Date: Mar 2019
Posts: 3,102
Funny story. A local township put up signs banning the use of "Jake Brakes" within township limits due to the noise. Jacobs sent them a cease and desist letter because they singled out a specific product and used their trademark to do it.

Turns out the township officials thought "Jake brake" was a generic term. They argued about the expense of changing their signs until their attorney explained the cost of defending against a trademark violation. New signs went up but they still have Jake Brake listed as a fine violation of $295

See the last item: https://www.richfieldvillageohio.org...r-Mayors-Court

I'd bet someone getting cited for using an engine brake that was not an actual Jake Brake could argue that one.

Ray
__________________
2020 Forest River Georgetown GT5 34H5
NXR is offline   Reply With Quote
Old 06-27-2021, 04:55 PM   #11
Senior Member
 
Join Date: Oct 2014
Posts: 3,920
Quote:
Originally Posted by Ted Lambert View Post

The retarder on the Allison transmission is hydraulic and uses transmission oil. They create a lot of heat which in turn makes tranny oil changes a must at regular intervals.

Correct, hence the more complex/effective cooling systems for transmissions with retarders. Generally reasonably large ATF to coolant coolers.


The good news, when on the retarder, the throttle is CLOSED, so the engine is generating little to no heat. Higher engine RPM circulates coolant and keeps the transmission temperature within a reasonable range.


This is particularly true with the more "heat tolerant" Transynd TES 295 and even more so for the Transynd TES 668.


SO, if you have an Allison transmission retarder (likely 90+% of transmission retarders) and on a long steep downgrade, keep the engine near the higher end of its RPM range. Same as you would for an engine compression brake or engine exhaust brake.
__________________
Brett Wolfe
Ex: 2003 Alpine 38FDDS. Ex: 1997 Safari Sahara. Ex: 1993 Foretravel U240
wolfe10 is online now   Reply With Quote
Reply

Tags
brake, exhaust



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Exhaust 'Jake brake' problem nuckels11 Monaco Owner's Forum 17 07-01-2021 04:03 PM
Jake Brake or Exhaust Brake tom076 Tiffin Owner's Forum 3 05-08-2016 02:28 PM
Jake exhaust brake lubing kiethco Freightliner Motorhome Chassis Forum 8 01-04-2015 09:09 AM
How important is an exhaust/jake brake? debrey Class A Motorhome Discussions 41 03-19-2013 09:24 AM
Two Position Jake Brake Switch - Any difference between up and down? GTHill Alpine Coach Owner's Forum 57 10-11-2011 09:53 PM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 04:46 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2021, vBulletin Solutions, Inc.