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Question on Supplemental Braking System

I'm looking for some advice regarding the necessity of a supplemental braking system on a 93 U-280. This particular coach has the 300 HP Cummins and Allison 6 speed but it does not have a Jake or exhaust brake or retarder. Assuming normal RV use which, of course, includes mountain driving, is a 280 safe without something to assist the service brakes (disc, air)?

Also, anyone have any experience regarding the difficulty and cost of adding on an exhaust brake on this setup.

Thanks. I'm going to post this over at rv.net too.
jor
93 225
95 300
97 270
99 320

Re: Question on Supplemental Braking System

Reply #1 –
You might want to look at some previous discussions on this.

http://foreforums.com/index.php?topic=3382.msg12400#msg12400

http://foreforums.com/index.php?topic=8430.msg36971#msg36971

http://foreforums.com/index.php?topic=3451.msg12708#msg12708

The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Question on Supplemental Braking System

Reply #2 –
I think I would look into spending the money on a jake or exhaust brake.  They make the mountains easy. If you use the brakes of the toad you will burn them up trying to stop the coach on a hill. To stop in a panic situation is a different story.

I drive in the mountains all the time and have the retarder on my FT and nothing on my Bornfree. It is a chore to drive the BF in the mountains and you have to know about stabbing the brakes and slowing way way down and using your gears. It is much harder without supplement restraint on the coach.

The tow brake requirement is a state requirement and a weight one as well.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Question on Supplemental Braking System

Reply #3 –
Quote
You might want to look at some previous discussions on this.

Thanks, Barry but If I have the right links, these all refer to toad braking system. My real concern is the necessity of a supplemental system on the coach.
jor
93 225
95 300
97 270
99 320

Re: Question on Supplemental Braking System

Reply #4 –
John,
 The air disc brakes will probably handle the grades as long as you begin the descent at 50 mph or less and downshift to keep the speed down.  I have the

4 speed, so it will be a bit different for you; on our 4 speed I start descending in 3rd, watching the rpm's and the speed.  When it gets much above 55, I use the brakes to get it below 50 again, and so on.  On really steep grades I slow down to 30 and downshift to 2nd, but you really have to watch the rpm's, because on the 300 Cummins, the redline is at the max 2400.
 I have an exhaust brake, but it isn't very effective.  I am sure that Dave

Head will add some comments regarding the PRXB (made by PAC Brake) that is probably the most effective add-on exhaust brake.  I have looked into getting one.  The brake itself is around $750-800, but heavy duty valve springs have to be installed first, then the electrical wiring up to the dash and labor to install the brake.  I estimate it might be $2000 total.
 Even with our existing BD exhaust brake, we have still are on our third set of brakes (and 2 rotors) in 7 years.  If the PRXB would reduce the wear, it would pay for itself within a couple years.
 Glad to see that you ended up with a 280, or are you still in the process of deciding?
 Don Hay

'92 U-280, The Hayfever Express
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Question on Supplemental Braking System

Reply #5 –
Quote
Glad to see that you ended up with a 280, or are you still in the process of deciding?
 Don Hay
We are STILL looking and this is the latest one. We've traveled to Colorado, Houston and Nevada but so far have eliminated each one. This one sounds about right but I am concerned about the lack of an exhaust brake. This is great info you've given me. Thanks.
93 225
95 300
97 270
99 320

Re: Question on Supplemental Braking System

Reply #6 –
Quote
Thanks, Barry but If I have the right links, these all refer to toad braking system. My real concern is the necessity of a supplemental system on the coach.

I misread. When you said Supplemental Braking, I thought you were referring to the toad. ???
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Question on Supplemental Braking System

Reply #7 –
John,

The reason I mentioned Dave Head and the PRXB is that his first Foretravel was a '93 U-280 and didn't have an exhaust brake when he bought it.  He had the PRXB installed and thought that it was worth the money.  When he bought his '95 U-320 he ended up with a Jake Brake (a step up from an exhaust brake), but still not as effective as the transmission retarder that became standard in all Foretravels beginning in '96.

Don Hay, '92 U280
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: Question on Supplemental Braking System

Reply #8 –
Having had the same coach - year and model, except with the 4 speed, I would say HECK NO (stronger terms, most likely).

Buy a PRXB pac brake, have it installed (you will likely have to have the HD valve springs installed too, Cummins can check your engine number and tell you).

After that, you will love going downhill, not fear it...
 
Quote
jor wrote:  A new topic, 'Question on Supplemental Braking System', has been made on  a board you are watching.    I'm looking for some advice regarding the necessity of a supplemental  braking system on a 93 U-280. this particular coach as the 300 HP  Cummins and Allison 6 speed but it does not have a Jake or exhaust brake  or retarder. Assuming normal RV use which, of course, includes mountain  driving, is a 280 safe without something to assist the service brakes  (disc, air)? Thanks. I'm going to post this over at rv.net too.  jor       
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

Re: Question on Supplemental Braking System

Reply #9 –
With a properly installed PRXB, starting down a 6% grade at 55 mph (I-24 going toward Chattanooga from Nashville) I had to cycle the PRXB off or it would slow the coach too much. I believe that is about a 3-4 mile grade.
 Prior to that fried my brakes going down the same hill.
 
Quote
Don Hay wrote:      John,  The air disc brakes will probably handle the grades as long as you begin  the descent at 50 mph or less and downshift to keep the speed down. I  have the    4 speed, so it will be a bit different for you; on our 4 speed I start  descending in 3rd, watching the rpm's and the speed. When it gets much  above 55, I use the brakes to get it below 50 again, and so on. On  really steep grades I slow down to 30 and downshift to 2nd, but you  really have to watch the rpm's, because on the 300 Cummins, the redline  is at the max 2400.  I have an exhaust brake, but it isn't very effective. I am sure that Dave    Head will add some comments regarding the PRXB (made by PAC Brake) that  is probably the most effective add-on exhaust brake. I have looked into  getting one. The brake itself is around $750-800, but heavy duty valve  springs have to be installed first, then the electrical wiring up to the  dash and labor to install the brake. I estimate it might be $2000 total.  Even with our existing BD exhaust brake, we have still are on our third  set of brakes (and 2 rotors) in 7 years. If the PRXB would reduce the  wear, it would pay for itself within a couple years.  Glad to see that you ended up with a 280, or are you still in the  process of deciding?  Don Hay    '92 U-280, The Hayfever Express       
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

Re: Question on Supplemental Braking System

Reply #10 –
Your 6 speed will brake better than a 4 speed with an exhaust brake, also. The MT series 4 speed torque converters only locked in 4th, or

3rd/4th depending on the model.

6 speeds lock up in every gear. This means the exhaust brake will work well in every gear.

You can also send a signal to the 6 speed telling it you have engaged a supplemental brake system and it will 'preselect' 4th (or a lower gear if programmed - 4th is default). This means as the coach slows it will auto downshift to attain that gear, keeping your exh braking force 'up'.

4 speeds were totally mechanical.
 Cost of kit (direct mount to outlet of turbo, most efficient) - about

$11-1200.00, then add labor of about 5 hundred (I ran my own for to aft wiring to save money). Add another 500 for valve springs. I would also order up a new turbo outlet flange because a coach that old will be rust pitted and leak like crazy - another hundred there.
 Peace of mind - PRICELESS!!!
 
 
Quote
Dave Head wrote:      Having had the same coach - year and model, except with the 4 speed, I  would say HECK NO (stronger terms, most likely).    Buy a PRXB pac brake, have it installed (you will likely have to have  the HD valve springs installed too, Cummins can check your engine number  and tell you).    After that, you will love going downhill, not fear it...  Quote 
Quote
jor wrote: A new topic, 'Question on Supplemental Braking System', has  been made on a board you are watching. I'm looking for some advice  regarding the necessity of a supplemental braking system on a 93 U-280.  this particular coach as the 300 HP Cummins and Allison 6 speed but it  does not have a Jake or exhaust brake or retarder. Assuming normal RV  use which, of course, includes mountain driving, is a 280 safe without  something to assist the service brakes (disc, air)? Thanks. I'm going to  post this over at rv.net too. jor     
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

Re: Question on Supplemental Braking System

Reply #11 –
Thanks to all for the info. It sounds as though I need to find one with the exhaust brake or retarder or add one on. I'm going to call a Cummins place today and see what they would charge. Thanks for the estimate, Dave.
jor
93 225
95 300
97 270
99 320
 

Re: Question on Supplemental Braking System

Reply #12 –
Pac brake installed on 93 U225 4 speed allison...Cost for lock-up kit, service ,transynd synthetic was $2,837.27 in June of 06.  Cost for Exhaust Brake Kit, Vlave spring Kit $870.00. Don't have price for labor as other things done at the same time.. (total Cummins bill was $7K...) The previous owner spent more on upgrades that I paid him for the coach..BUT, I got a coach that everything was new.

I have put 20,000 plus miles on this coach in 2 1/2 years and one time pac brake (broken wire) was not working....FIXED that real fast...

This was done before I bought the coach so not sure what the lock-up kit was for. 

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