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94 U280 Pac Brake Switch

Just getting into readying my coach for a nice trip in the spring and last year I had a problem just before I put it away for the winter. When I bought the coach back in 2013 the previous owner had his transmission removed to replace the rear main seal on the engine. Almost a week later he took it back and told the shop the Pac Brake did not work. Well they said it needed a switch on the dash and put in a spst toggle switch next to the ignition switch and a complete wire assy. to the Pac Brake. They then charge him almost $900 for this. Now the screw connections have come loose and almost completely undone. I think that when they took the transmission out they either forgot to reconnect something or damaged the wire and did not repair it, just my speculation. Why would Foretravel not have a rocker switch already on the dash for this? I have a rocker switch right beside the Ether control that does nothing but is powered. As I was reading in the manual that was for the optional retarder but to my thinking why would Foretravel not use that rocker switch for the Pac Brake if that was not used for the retarder to keep things consistent. Also, if it is not used why would it be there wired and powered as the light comes on when the rocker is activated. There is no labeling on the dash as with all other rockers that signify it purpose? If it is for the Pac Brake put in at the factory I will rewire to that switch as I don't like the type of connections at the toggle switch and doing it properly through a rocker switch would be much more preferable with the light activated when on. In any case I think I will avoid the shop that did the work.

The next time I'm at the coach I will try to trace the wiring from the switch since the wiring in the manual does not cover any switches nor the Pac Brake. If the Pac Brake had not stopped working I would not have asked this question thinking that the rocker switch was for an option I did not have. I have a strong feeling it was for the Pac Brake originally. It has a black ground wire (about 16 ga) and a light green wire (about 14 ga) to and from the switch. Anyone that might be able to shed some light on this, it would sure be helpful. It will save me a lot of scratch marks on my head trying to figure out the purpose.

Thanks,
John
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #1
The PAC brake on my rig is powered from a step on switch that is located on the floor to the right of the steering column.  I have a couple of extra switches on my dash also, so I;m not sure that any of those were ever intended for a PAC brake.  I don't have any wiring diagrams that show a PAC brake.  FT may be able to shed some light on this for you.  ----  Have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: 94 U280 Pac Brake Switch

Reply #2
Thanks Fritz!

It is good to know that I may have an extra rocker already in place. I'll see what James Triana has to say when he gives me a call back on that. I know that the coaches configuration may change quite a bit depending on model and options. It is nice to have an illuminated switch to remind you that it is active so you don't leave it on when trying to coast. It has worked well for years but when it stopped functioning it made me look into the past owners receipts. I had made sure everything was free on the engine side and lubricated it at the start and end of each trip so I knew that it was not a seized gate. I was surprised to find multiple loose connections and they are not that easy to get to without removing the radio and cigarette lighter housing. I was hoping that it was a simple mistake that can be corrected easily which yet may well be. I had been eyeing that rocker for some time wondering what it was for and if it could be used for something in the future like the Pac Brake. I did not think that Foretravel would hard wire the Pac Brake to be on all the time as was suggested by the shop that had previously did the work.

Thanks for your enlightenment and reply.

Regards,
John
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #3
Maybe Mike Leary has a wiring diagram for a pac brake. My exhaust brake has a master switch to turn to automatic mode, let off completely on the accelerator pedal and the exhaust brake engages. Can still coast down hills be just resting my foot on the pedal.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: 94 U280 Pac Brake Switch

Reply #4
John,

Do you have some paperwork that indicates your exhaust brake was installed at the factory?  I don't see any mention of it in the beamalarm spec sheet for your coach.  I am wondering if it was added after the coach left the factory, by one of the prior owners.  In that case, it is anybody's guess how it was wired.

1994 Foretravel U280 Specifications

I apparently don't have the "extra" unused switch on my coach.  My exhaust brake is operated by a add-on switch on the wall next to driver seat.  See photos below.  On my brake, which was added by a prior owner, when I turn it on (arm it), then it operates automatically.  If I release pressure on the throttle pedal, brake closes.  When I apply foot pressure to throttle pedal, it opens.

I suppose it is possible the extra switch on your dash was used to operate your exhaust brake.  Good luck tracing the wires!

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
"It goes without saying..."

Re: 94 U280 Pac Brake Switch

Reply #5
Mine is quite similar to Chuck's, let totaly off the gas and engages and can also be switched to show brake lights while engaged. Will attempt to post a photo tomorrow. Red indicater lights for both functions. Best bet would probably be Mike Leary for wiring diagram as his coach is very documented.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: 94 U280 Pac Brake Switch

Reply #6
Now this gives me more to ask James Triana when we talk. To bad they did not do what most car makers do including build sheets all through out the interior of the car. I looked at all the documentation and it does not show anywhere either being built at the factory with nor added late on, so Chuck you are quite right it could be anyone guess. Mine operated fine when left on and just operated when taking your foot off the accelerator and disengaged when throttle was applied. My dash is identical to yours except for the one extra illuminated rocker between the Ether and the Park Brake and the one you just added for your Battery boost setup.

Old Phart Phred has given me another avenue to go as far as getting wiring info on the Pac Brake from Mike Leary. Even if it is factory installed I would like to have at least a basic wiring diagram on how it is supposed to be wired. One note I found is that when the previous owner took delivery of it, it was gone over by FOT and they showed him how to operate the Pac Brake but even then there was an issue that he was to deal with at a later date but I had no paperwork for that if it was performed other than the switch added before I purchased it.

I want to thank you both for your response and help on this one. When it is rectified it will certainly ease my mind knowing it is done to a better degree that will not fall apart later going down the road with a positive wire floating around under the dash looking to cause problems. As I get older I need all the help I can get as in seeing a bright light on the dash telling me the Pac Brake is on or when I forgot to turn it off. I guess too I will have to look on line to see the proper function and operation of the Pac Brake. I had thought about getting a 2 stage unit until I looked at the price. The reality is that the one I have does enough to help on slowing things down in the mountains now. I have been looking for a large anchor, even if it is wood and painted like a ship anchor, to mount on the back with a chain attached and a sign that reads, please stay back at least 50 feet, emergency brake activated. It should get a laugh or 2 and less people tailgating.

Thanks to all for the help,
John
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #7
I have the pac-brake on mine. It is wired into a spare rocker switch in the dash to the left of the 2 dock light switches. Foretravel never installed a pac-brake on any motorhome that I know of. As far as I'm concerned, and this is my second Foretravel with a pac-brake, it is worthless.
1994 U280, Build 4490
Deming, NM.

Re: 94 U280 Pac Brake Switch

Reply #8
I'll check my files today for a any wiring schematics.  Here's mine, with the custom console (done by Brett, natch!). The PacBrake on/off is at the bottom of the shifter. BTW, I LOVE OURS!  ^.^d  ^.^d  ^.^d  I show our's was installed in 04,"PRXB New Generation", serial # 082658. It was made for the 3116/3126 CAT engines.
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: 94 U280 Pac Brake Switch

Reply #9
I found the files! There a quite a few pages, so I can make copies for anyone. The print is so small, that would be a challenge to read on a computer screen. Any one can send me a PM with their address, and I'll have our local printers do it and mail it out.  ^.^d
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: 94 U280 Pac Brake Switch

Reply #10
I notice the files for the '94 280 mentioned  having a Cummins engine, but the same 3060 Allison MD World 6-speed as ours. I'd think a call to PacBrake would be in order, just to make sure my files will be of help.  ^.^d
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: 94 U280 Pac Brake Switch

Reply #11
First off, this morning I received a much awaited phone call from James Triana. He mentioned that my coach came without the Pac Brake and that it must have been done by a previous owner, which would have been the original owner. As far as the spare rocker on the dash that would have been an after purchase add on for, a big question mark, but I getting the assumption it may have originally been the Pac Brake On/Off master switch. Now I just have to trace the wiring as it does not look to be by Foretravel at this point in time.

In the response from Twigg. I concur with you in that it does not have much strength but any assist which I have noticed on a 6% grade is helpful and lengthens the life of the service brakes by a little as well as using a lower gear and running below the speed limit. I don't like it when it exceeds 80 mph which I did only once. It is abuse of equipment and I gave my head a shake afterward plus a kick in the butt. I've seen the aftermath of too many accidents from people doing stupid things in my day and don't want to add to them. I don't need to get anywhere fast or in a short period of time. I got myself out of the military habit of "hurry up and wait".

Thank you Mike for joining and responding to my request. Yes, I will get a hold of Pac Brake on the phone and try to stop by their office this week to try to get further info. I'll hold off on the wiring request, Mike, until I talk to Pac Brake to see what I can get out of them first. Thank you immensely for effort in finding your documentation. By the way I do have a big magnifying glass for the computer screen too, just kidding. It seems that a lot of manufactures are going to micro-fine print that is bordering on microfiche in their printing.

I will dig in to the tracing of the wires next week and post what I come up with. Thanks to all for the help and suggestions, now it is up to me to get 'er done. At least now I feel like I'm not chasing a wire needlessly and that I have a game plan and resources at hand. :)

Later and many thanks for your responses,
John
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #12
I don't want to get into a debate on the value of a exhaust brake, BUT, Twig's opinion (that the Pacbrake is worthless) does not match my opinion (of our exhaust brake).  I know they are two different brands, but they seem to operate in a similar manner.  We have been over the Rockies several times, and I have found our exhaust brake to be a great help in descending long, steep grades.  Of course, a exhaust brake will never match the performance of a hydraulic transmission retarder, but if I had to choose between having our exhaust brake or nothing at all, I would certainly rather have our brake.

We have descended many long downhill roads with SOB coaches in front of us.  They are riding their brakes all the way down the hill, while we coast down serenely in 4th gear at about 2000 RPM and our exhaust brake activated.  In many cases I never have to touch the service brakes.  A properly maintained exhaust brake, that is functioning correctly and operated properly, will take a big load off your disk brakes when driving in the mountains.

That is only my opinion - take it for what it is worth.
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
"It goes without saying..."

Re: 94 U280 Pac Brake Switch

Reply #13
You can get wiring diagrams for installing a PacBrake from them. 

Generally, it is wired through the Allison ECM so it achieves a downshift as well as exhaust brake application.
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: 94 U280 Pac Brake Switch

Reply #14
  In many cases I never have to touch the service brakes.  A properly maintained exhaust brake, that is functioning correctly and operated properly, will take a big load off your disk brakes when driving in the mountains.
Having had a PacBrake installed (and maintained) since 04, is the BIG reason our drum brakes have lasted so well. I would add, both previous owners KNEW how to drive slopes! 
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: 94 U280 Pac Brake Switch

Reply #15
Thanks Brett for your input as I have never seen any documentation or wiring for the Pac Brake but it is very important to know. I had no idea that it went through the ECM so that is good to know so I can narrow my wire tracing as well. That is why I'm trying to get mine in service again as I cross the Siskiyou Mountains enough to enjoy the added help of our Pac Brake. It is an advantage and used right a very big safety feature. I too would rather have the Pac than nothing as it gives you peace of mind and it does not raise the transmission temp while in use. But as I mentioned that I'm not in a rush to get anywhere in retirement as the final resting place is coming up too fast anyway and I don't want to meet it half way there.

I also totally agree with Chuck & Mike that you have to maintain (lube the proper points) so that they don't seize in the exhaust. That was one of the things I first got when I bought my coach was a bottle of lubricant for that specific purpose. It is much nicer to descend at a slower leisurely pace than find yourself between a rock and a hard place in a sharp corner with items cascading through the coach or worse. That is why I want the added feature of knowing via the illuminated rocker that I have it activated and that I did not forget it in my old age or just watching the scenery.

I was feeling almost ashamed of bring this matter up on the forum. Now I know more and maybe others might change their opinions of this sometimes poo pooed item if used properly. I feel I'm always learning and never regret even the smallest or seemingly most insignificant item can be given it's true value with a little knowledge. I really appreciate all the input from everyone.

Thanks, ^.^d
John

 
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #16
These are the best I could get since they are not originals, but FAX. Hope they can help.
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: 94 U280 Pac Brake Switch

Reply #17
This is more than what I expected, thanks Mike! Now, this gave me another possible avenue to look into as I had my ECM redone about the same time but I had not done any mountain travel for quite a while afterwards and since not really going fast and I did not bother using the Pac Brake. I'm wondering when it was rebuilt, if the settings had been changed and would need to be activated again, just a thought? I had it redone by Transmission Instruments so I may just give them a call to see if the setting may have been changed. I will be able to start looking for what is what and also to go out for a test drive first just to see if tightening the connections had done the trick. If not I will place a call and start checking all the connections and wired that I can.

Get that end solved, then tackle the other moving the wires to an illuminated rocker switch.

Thanks, Mike, for the 2 pics as it gives me something to ponder on so I can have a better point of reference as to what is happening and where to look.

Regards,
John

John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #18
I checked the location of Pac Brake Corporate Headquarters is only 20 minutes from my home so that is very convenient and if I have problems then I can always take it to them if they are can do further diagnosis. That is lucky for sure to be so close. One of my neighbors is or was a sales person for them but he moved out of my area unfortunately. So that is a Monday morning trip on the way to the coach and shopping.

John
John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #19
I checked the location of Pac Brake Corporate Headquarters is only 20 minutes from my home so that is very convenient and if I have problems then I can always take it to them if they are can do further diagnosis. That is lucky for sure to be so close. One of my neighbors is or was a sales person for them but he moved out of my area unfortunately. So that is a Monday morning trip on the way to the coach and shopping.

John
How often does THAT happen to any of us?  b^.^d
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: 94 U280 Pac Brake Switch

Reply #20
My exhaust brake (haven't looked at the brand) is commanded by the switch marked retartder but only lights up and activates when switch is on and brakes are applied.
Toby a 94 u280
Cummins 8.3
6 speed Allison
Exhaust brake


Adopted by Derek and Annabelle

Re: 94 U280 Pac Brake Switch

Reply #21
I have to add on to this. My PacBrake is a foot pedal to the left of the steering column., no additional switches on the dash. I have found it great for 6% & 7% grades when shifted down to 4th (feels the best for speed and control). It will slow me down at exits (not quite to a stop, but in combination with the brakes, gets me stopped a lot faster with less effort). Replaced my frozen one about 1 1/2 years ago and feel much better taking long steep grades.
AKA Chuck
1993 U280 40' WTB, Build 4345, CUM 8.3 "Falcor", 2002 Jeep GC TOAD, 920W solar on roof
Full-Time traveler between Quartzsite AZ, Longview WA, Helena MT, Ellendale ND, and Lake City SD
The selected media item is not currently available.

Re: 94 U280 Pac Brake Switch

Reply #22
I visited Pac Brakes Head Office in Surrey, BC yesterday looking for info on my Pac Brake for 8.3 Cummins/MD3060 Allison. As it turned out the gave the info freely to me printing it out there on the spot which was quite nice of them. When I got home I read the material showed me that I knew far less about the operation than I thought and the different configurations of installation in the coach and how they are set up according to the owner and installer, so it can differ quite a bit. So this morning I got hold of Chris Lacey at Pac Brake again but on the phone and asked if he could possibly send me .pdf files to me so I could get them to interested parties on the Forum. He was more than happy to do that and now I have them in my possession. Now, I don't know the best way of posting the .pdf files here so they can be shared with interested parties and they also have many links on operation so the Pac Brake can be used more effectively which I learned a lot. I know others are probably in the same boat in that way which a little nudge in reading this info would certainly help. Also, Chris included a trouble shooting guide, also helpful and one that he did not include was the "How An Exhaust Brake Works / Exhaust Brake Driving Tips" which is easily downloadable from the Pac Brake site.

On my coach the Pac Brake was put on by the original owner just after he purchased it from what I can tell, but the configuration is still unknown. The second owner, I think, did not use it enough and had problems with it at which point someone added a switch that was supposed to operate the Pac Brake but lately it stopped working and that is the reason I'm doing this search of answers to bring it to life again. I had maintained it over the years that I had it and seemed to function alright but not to any great degree of stopping power for such a expensive item. Well, that I can blame on me for not knowing how to use it properly and the way it is configured in my coach at present is not the best way but the easiest or possibly the cheapest way and yet not the most efficient. Now I have to find out what was on the original configuration if I can and go from there but with this new info from Pac Brake at least now I have a good starting point and the reasons for doing each configuration.

I hope that this info may be able to help others and find it's way into the permanent files where everyone may make use of them in the future. Now, I just have to find out how to get it loaded here.

John

John Smith
1994 U280 36' John, Pauline, & Marley Cat
2010 Ford Fusion

Re: 94 U280 Pac Brake Switch

Reply #23
That's great to be able to bond with the factory, John!  Our's was installed in '04 and called the "PRXB' New Generation". Serial # 082658. It was last lubed in 2015, so I should check when it needs service. I sure like it,  but as we've talked about, it takes some experience before one goes chargin' down a 7% grade at 65 and expects the PB to act like a 'Jake'.
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: 94 U280 Pac Brake Switch

Reply #24
I hope that this info may be able to help others and find it's way into the permanent files where everyone may make use of them in the future. Now, I just have to find out how to get it loaded here.
John,

You can upload .pdf files within a post just like you do a photo.  Use the "Add Files..." button at the bottom of the page, find the .pdf files on your computer, and click them to upload.

OR, you can add them to the Forum Library.  Use the link below to the Library.  Pick the folder that seems most appropriate to you, or start a new folder.  Move to that folder, and then use the "Add Item" button at top of page to upload the .pdf files.

http://www.foreforums.com/index.php?action=media;sa=album;in=165
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
"It goes without saying..."