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Topic: Jake Brake or Pac Brake on a Cummins (Read 752 times) previous topic - next topic

Jake Brake or Pac Brake on a Cummins

I have 1993 U280 with no jake brake,,, Cummins says they can put one on the parts are 1700.00 not with labor.
I have looked on Google some say Pac Brake is the same as Jake . Is that true?
I live in Northwest and need something to assist the mountains
Would any please let me know if they have added a Jake to their Cummins with six speed Allison, I believe 300hp
Rick
509-939-0740
rlmlimited@comcast.net

Re: Jake Brake or Pac Brake on a Cummins

Reply #1 –
Terminology.  Are you asking about adding a "compression release brake" or a "exhaust brake".  Big difference in complexity and cost.

Compression release engine brake - Wikipedia

Supplemental Brakes | Pacbrake
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Jake Brake or Pac Brake on a Cummins

Reply #2 –
We had a PAC brake on our 1993, U225. It was OK for going down hill but did little else. We now have a Jake or Compression brake on our 1993, U300. I leave the Jake on all of the time and it helps with braking in day to day driving. With that said it is my understanding that the current PAC brake has much better performance that the old one I had on the U225. Based on the cost I would choose the PAC  brake for your 1993 coach.

Both brakes are more effective at higher engine rpms. One very good rule of thumb is go down hill in the lowest gear you went up the hill. If you coach shifts down to fourth or even third gear going up, start the down hill run in that same gear. Once your speed is up you may not be able to downshift without over revving your engine. Many transmissions will not allow you to down shift at that point.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Jake Brake or Pac Brake on a Cummins

Reply #3 –
Are the newer Jake Brakes quieter than the ones I remember in the PNW as logging trucks came down the hill?
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Jake Brake or Pac Brake on a Cummins

Reply #4 –
NO, they can not put a jake brake/engine compression brake on a Cummins C engine.  The Cummins L is the smallest engine that can be fit with one.

What they can do is add an exhaust brake. 

I would contact PacBrake with your Cummins engine serial number to find out if they have a PRXB style exhaust brake for your engine.  And, if so, what PSI your engine can handle without replacing the valve springs.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Jake Brake or Pac Brake on a Cummins

Reply #5 –
Quote from: ricker –
I have 1993 U280 with no jake brake,,, Cummins says they can put one on the parts are 1700.00 not with labor.
I have looked on Google some say Pac Brake is the same as Jake . Is that true?
Pacbrake is a company name. They manufacturer several types of engine brakes. Here is their website: Diesel Emission Valves, Engine Brakes and Exhaust Brakes

Love the Jake on our Detroit. Works well at higher rpms and since we have the stock muffler, I leave it on most of the time without worrying about Jake (noise) restricted areas. I keeps the four exhaust valves in each cylinder open when you are off the throttle. Jake is a trademarked name. Your electric drill has a Jacobs chuck. Same guy.

Check the chart here. Looks like over 100 hp of braking at 2000 rpm. Cummins QuickServe Online

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)
 

Re: Jake Brake or Pac Brake on a Cummins

Reply #6 –
Jacobs offers an exhaust brake, but the PRXB by PAC brake and the Decelerator by US Gear are newer designs that brake better than a standard exh brake. You will be happy with either. Cummins needs to verify if you have the heavy duty valve springs - the change occurred that year. You save significantly on the install cost. My '93 did not. Great difference in the mountains.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT