Need some backup on Jacobs/Cummins parts before I spend $$

[Northfork]

A month or so ago we ordered a Jakobs Brake Kit for my truck through a Cummins parts retailer. They used my Vin to source the right kit. The kit was one of only a couple still on the
shelves, or so I was told. the Cummins Full Kit Part # is 2881840.

(I know others prefer the BD and PAC brakes, been there done that on other trucks and I like the Jake, just me)

I am awaiting better weather and due to the aftermarket parts in my spine I am leaning towards having a local shop I trust do the install, but it couldn't keep me from opening the box and snooping a bit, LOL. Inside I found a bag with a small round rocker switch. This switch is designed to be put in the dash, on the left side. It has a "picture" of a headlight on it and a blue LED., with the hieroglyphic installation instructions.

After thinking about this I would prefer a push pull switch on the six-speed manual shifter. I don't want to be swapping hands on the steering wheel while shifting, steering, and working the brake. After trying (and failing) in finding an online route to source Cummins part numbers and diagrams I went to www.moparpartswebstore.com and found a usable breakout diagram and a Mopar part number for this switch, that number being #05102082 AB. It shows this switch matches the mopar # for the brake, just want to be sure I can substitute this switch for the in dash deal when we do the install...ready to push the buy button when confirmed...

I have an email in to Jakobs on their customer service website, but was hoping one of you guys with more time in the Cummins Mopar world might be able to solve this for me...thanks

 

[ScottLewis]

I had the dealer install a Jacobs exhaust brake when I bought my '06. I have a Auto with shift on the tree. They installed a standard pull switch on the shift lever.The Jacobs vacuum pump went out at about 65K miles and I then installed a Pac brake with on-board air compressor. In my opinion, there isn't a lot of performance difference between the Jacobs and the Pac or for the BD I had on my previous '98. Your stick shift operates different from my auto but may be controlled by the ECM like mine. Read the install info that comes with the brake. It may be easier than you think.

 

[Northfork]

Thank you for your input, I've read the install stuff more than once. The unit does interface with the ECM, the instructions indicate the wiring hookup.
I know I can do this, it is just that there is a price I pay for taking on tasks like this that require a lot of bending, crawling around under the truck and the dash, etc I have an old-school Diesel truck repair facility in town that I have been doing business with since I bought my first diesel truck, a 1984 (?) GMC 2wd 3+3 Camper Special crew cab dually with the amazingly dull 6.2. I am weighing whether I
want to pay that price right now. I am hoping to put off another surgery for as long as possible.
I have several friends with Dodge/Cummins trucks and have driven all but the brand new Pac Brake many miles. We have a stash of spares for this Jake application, and a family member has an identical truck to mine with the Jake. I like it.

I can wait for Cummins to confirm my part number inquiry, just hoping to pick the brains of the experts here before dropping the $. As I have gotten older I don't part with my $ as easily as I used to.

 

[petersonj]

After thinking about this I would prefer a push pull switch on the six-speed manual shifter.

Just my two cents here. The dash is the worst place to put the exhaust brake control switch, the shifter is the second best place, but a momentary switch beside your left foot on the floor is by far the best place for a switch.

The benefits of a floor switch are ease of operation, both hands can stay on the steering wheel, and during a gear change your left foot comes off of the foot switch to depress the clutch pedal. Because of the seamless operation you will find that you will consistently use the exhaust brake without even thinking about it.

On my truck I installed a three position maintained switch in the dash. It has three purposes. 1) turn off power to the foot switch, 2) supply power to the foot switch (normal operation), and 3) turn on the exhaust brake to warm up the engine faster.

I have driven over 330,000 miles with this setup (70,000 miles on my last truck and 265,000 miles on my current truck) and I wouldn't have it any other way. I have wired two manual transmission trucks for friends in this same manner and they are both very happy with the results.

Just an idea...

- John

 

[lpennock]

The mounting of the switch is a don't care. The way the brake works you can leave it on at all times and the few times you would shut it off are just as easy to hit the dash switch. With that said if you want the switch that mounts to the stick I think you need

Stalk Switch
Cummins P/N 4089657
Mopar P/N 05102082AB

Now to clarify why I say having the switch is a don't care. On a 06/07 The brake is fully integrated with the ECU so its operation is pretty automatic if you just leave it on.
1. It only comes on when the accelerator is fully released except when you are have cruise on (see next item). So if you need to disengage it rapidly just lightly touch accelerator pedal. In addition it has a slight delay when engaging to allow you to down shift. Makes it very easy to control slowing.
2. With cruise engaged the ECU will command braking if needed to slow you down on a grade. You don't need to do anything, it just turns the brake on and off as needed.
3. The ECU will turn on the brake during cold start to help the engine warm up (<175 degree coolant temp). Only turns it on when you are idling and will shut it off as soon as you touch the accelerator.

The only time you need to shut if off by hand is when you are on snow/ice were having the additional braking would cause the back end to break loose, in which case you are going to shut it off and leave it off so hitting the dash switch is not a problem.

I have the shifter mounted switch and my brake is always on so it is mostly for decoration.

 

[mwilson]

Northfork,

I have installed the Jake Kit on my '06 and have been quite happy with it. The vacuum pump will crap out at some point, mine died with around 100,000 miles of run time on it Keep your old belt behind the seat so you can bypass the vacuum pump and keep on trucking. When you replace it get the heavy duty version that Geno's sells and carry on.

I recall the hardest part of the install was holding the brake unit, gasket and clamp in place. Then having to tighten the clamp while not letting the brake move out of position. If you have a stiff back you are wise to have someone else do that part at least for you.

I would use a clutch switch in lieu of the floor mounted switch mentioned above. Jacobs makes one. Back when the dinosaurs roamed the earth and trucks had (Gasp!) no electronics that's how we drivers controlled the brake. The true Jake would stall the engine if you forgot to shut it off after putting the truck in neutral and coming to a stop. Other than that we left the Jake brake on all the time and controlled it with the clutch switch.

Using the clutch switch in your Ram would make it worry free for every shift plus you could just leave the brake switch on all of the time as I do with my automatic. Never shut if off.

I will provide graphics / part numbers of both the push pull switch as you requested and the clutch switch. You've caught me on a rare day off so I should be able to answer any more questions as the day goes on. Have to spend a little time in the garage with my snowblower but that is it for today's list. A nap by the wood stove may be on the menu for this afternoon....but time will tell...


Here is the push pull switch that you inquired about...4089657. Should be around $80.00 or so if you can find one. They were discontinued in 2008 due to a chronic rattling issue. Replaced by the switch that is in your kit. You can have your Cummins dealer do a search for dusty old inventory but will be a long shot at this point.

 

[mwilson]

You could also refit a a push pull shifter mounted switch used on big trucks for a two speed rear end. I can try and help if you elect that option.

 

[mwilson]

Now here is what I would do...use the on-off switch provided with your kit and add this switch.

3871397 is the Cummins number for the kit. Should be around $60.00 or so and most every Cummins distributor has them on the shelf.

 

[mwilson]

And as lpennock says above you may not even need the clutch switch. I assume that he has a manual transmission.

 

[lpennock]

And as lpennock says above you may not even need the clutch switch. I assume that he has a manual transmission.

Yes I have a G56. My brake stays enabled all the time even though I do have the shifter mounted switch. The ECU integration makes it mindless operation so the switch is just left on.

 

[p-Bar]

BD sells the switch for the manual transmission. Also another neat idea is using the highbeam switch we grew up with (old guys)

 

[Northfork]

Wow....thank you all very much for the all of the responses and the information on how it all works. With the ECU integration it seems like my concerns are unfounded. I will probably just use the switch included in the kit at this point. Really, thanks everyone!

 

[Motorhead]

Northfork, Seeing that your truck is the same as mine, I don't think you will like the dash switch. As you drive your truck, you won't want the exhaust brake activating every time you let off of the throttle. It makes shifting rough having the brake come on when you are trying to shift. I don't have a clutch switch as the ECM takes care of that. I have used the BD shifter mount with the old style, red button two speed axle switch. I stripped the outer sheath off of the electrical cord they used and ran the wires down the shifter stalk then put a piece of shrink tube over the shift stalk and wires all the way down to the shift boot. I can post a picture of it if you want. The switch on the stick shift is very easy to access. The other thing I did for an install on an automatic Dodge which will work for the stick shift too was put an old style headlight dimmer switch on the left floor board just below the emergency brake pedal. You would press it to turn it on and it would stay on other than when you were into the throttle until you tapped it again to shut it off. Here is the link to the BD switch and aluminum shifter clamp. http://www.ebay.com/itm/BD-Diesel-1...ash=item5d56c1ea35:g:lJoAAOSwrklVcj48&vxp=mtr

 

[AH64ID]

I had the push-pull switch and removed it due to the rattling issues that eventually led to the switch being discontinued.

I ordered the switch that Pac Brake includes with their kit and installed it instead. I am much happier with this setup.

For shifting there is a built in delay (based on accelerator position) so standard speed up-shifts aren't effected by leaving the switch on. If you take a long time to shift then it may actuate, but this rarely ever happens. For downshifting you want it to stay engaged so that when you let the clutch out your already braking instead of waiting for the EB to reengage.

I would also steer clear of a momentary switch. The beauty of the ECM controlled exhaust brake is that it's just that, ECM controlled. It's not on when it shouldn't be and it's on when it should be.

 

[Northfork]

Well I just ordered the shifter switch. Stick with my initial plan and if it turns south I will have the dash switch to fall back on.
I appreciate all the response guys. Will let you know how it goes.

 

[Motorhead]

I had the push-pull switch and removed it due to the rattling issues that eventually led to the switch being discontinued.

I ordered the switch that Pac Brake includes with their kit and installed it instead. I am much happier with this setup.

For shifting there is a built in delay (based on accelerator position) so standard speed up-shifts aren't effected by leaving the switch on. If you take a long time to shift then it may actuate, but this rarely ever happens. For downshifting you want it to stay engaged so that when you let the clutch out your already braking instead of waiting for the EB to reengage.

I would also steer clear of a momentary switch. The beauty of the ECM controlled exhaust brake is that it's just that, ECM controlled. It's not on when it shouldn't be and it's on when it should be.

I have used for years a silicone hair band that I wrap once around the shifter, turn it 180 degrees (X it) then wrap it around the switch stalk. No rattle. I snitched the bands from my youngest daughter.
https://www.walgreens.com/store/c/scunci-no-slip-grip-the-evolution-hair-ties/ID=prod6022124-product

 

[AH64ID]

I have used for years a silicone hair band that I wrap once around the shifter, turn it 180 degrees (X it) then wrap it around the switch stalk. No rattle. I snitched the bands from my youngest daughter.
https://www.walgreens.com/store/c/scunci-no-slip-grip-the-evolution-hair-ties/ID=prod6022124-product

I tried all the common tricks to no avail. Oddly enough my dads 06 has had one since 06 with no rattle.

I went thru 2 under warranty before swapping it for the Pac Brake switch.

 

[Motorhead]

My switch went 10-15,000 miles before rattling. I used rubber bands for a while but they deteriorated after a while. switched to the silicone band and no degrade. The push pull button for me is right in the right place and very easy to find and use.
(Sure loving that TURBO John!)

 

[Northfork]

The switch arrived...wrong one. Called the place and they said I was right, the part number is for the push-pull switch...they do not know why I was sent the rocker switch, (the one I already have).
He said they don't have a push pull in stock, but will they will get one to me....so my install will wait again.
Might have to use that BD switch if they can't find one. I may need that wiring info to get it to work. Will ask for help if it comes to that.

 

[Northfork]

Northfork, Seeing that your truck is the same as mine, I don't think you will like the dash switch. As you drive your truck, you won't want the exhaust brake activating every time you let off of the throttle. It makes shifting rough having the brake come on when you are trying to shift. I don't have a clutch switch as the ECM takes care of that. I have used the BD shifter mount with the old style, red button two speed axle switch. I stripped the outer sheath off of the electrical cord they used and ran the wires down the shifter stalk then put a piece of shrink tube over the shift stalk and wires all the way down to the shift boot. I can post a picture of it if you want. The switch on the stick shift is very easy to access. The other thing I did for an install on an automatic Dodge which will work for the stick shift too was put an old style headlight dimmer switch on the left floor board just below the emergency brake pedal. You would press it to turn it on and it would stay on other than when you were into the throttle until you tapped it again to shut it off. Here is the link to the BD switch and aluminum shifter clamp. http://www.ebay.com/itm/BD-Diesel-1...ash=item5d56c1ea35:g:lJoAAOSwrklVcj48&vxp=mtr

Motorhead I have struck out on finding new old stock of the Cummins/Mopar switch. Can you tell me how you wired the BD switch in to the Jake harness to operate the brake on the 07?