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My Exhaust  brake works when applied ... but even if I downshift manually the transmission will upshift when it hits a certain rpm ... then I apply my brakes to reduce the speed and keep the Exhaust brake on !
The brakes ..drums shoes , the entire system was replaced last year.
This has caused a few hair raising times and some hot brakes ..... Is there a problem with the system or am I doing something wrong ?
This is on a 2002 38 foot windsor with 62000 miles ,,, transmission has been serviced at the same times as brakes were done !
Thanks in advance !!
 

 

 

 

 

 

 

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Your system seems to acting differently then mine.

I leave my exhaust brake off until I need it.  When I turn it the transmission drops to 2nd gear, as long as I don't hit the accelerator it stays in 2nd gear.  If I turn on my cruise it disables the exhaust brake but if I start braking the exhaust brake kicks in. 

Not sure what the remedy may be, hopefully someone will chime in.

 

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What you describe is normal. The Exhaust brake can only do so much to hold (or slow) the coach speed downhill (depending on weight of coach and road grade). Once the engine reaches a certain speed the transmission will up shift to protect the engine from over speeding. You have to then brake hard and steady to get the speed back down.

The gear that the transmission goes to when the exhaust brake is turned on is "programmed to". On my coach it is set for 4th gear. It will not just "drop" into 4th (the vehicle/engine speed needs to be in the proper range for that gear).  So say you're moving at 50 mph down a steep grade (in 6th gear), you use the brakes and exhaust brake to slow down, and the transmission will downshift to 5th as you slow then into 4th.  It will stay in 4th with engine rpm at, say 2100 - 2400, but if the down hill speed starts to increase again (hill is just too steep) you have to step on the brakes again or transmission will up shift,

Edited by CountryB
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3 hours ago, ukondew said:

My Exhaust  brake works when applied ... but even if I downshift manually the transmission will upshift when it hits a certain rpm ... then I apply my brakes to reduce the speed and keep the Exhaust brake on !
The brakes ..drums shoes , the entire system was replaced last year.
This has caused a few hair raising times and some hot brakes ..... Is there a problem with the system or am I doing something wrong ?
This is on a 2002 38 foot windsor with 62000 miles ,,, transmission has been serviced at the same times as brakes were done !
Thanks in advance !!

As others say it sounds like it is acting normal.  Have you lubed the exhaust brake?  Pac Brake Lube   Exhaust Brake info
 

 

 

 

 

 

 

 

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When my engine brake engages it downshifts to 4th if I'm going slow enough.  I've learned to hit the top of hills at the speed I want to descend.  That speed is generally between 45 and 50 because my coach will be approaching 2100 RPM in 4th at 50.  Generally my coach Jake brake will hold the coach under 50 on 90% of the descents I've encountered out West and on the way to and from Alaska.  If I have to brake on a descent I will brake relatively hard for a short period of time letting off the brake so they can cool.  When descending I generally have to accelerate periodically to maintain 45-50.  Most important points, speed at top of hill low and brake hard for short periods, do not ride the brake!!  Hope I'm not telling you stuff you already know.  Good luck!!

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11 minutes ago, Jemert said:

When my engine brake engages it downshifts to 4th if I'm going slow enough.  I've learned to hit the top of hills at the speed I want to descend.  That speed is generally between 45 and 50 because my coach will be approaching 2100 RPM in 4th at 50.  Generally my coach Jake brake will hold the coach under 50 on 90% of the descents I've encountered out West and on the way to and from Alaska.  If I have to brake on a descent I will brake relatively hard for a short period of time letting off the brake so they can cool.  When descending I generally have to accelerate periodically to maintain 45-50.  Most important points, speed at top of hill low and brake hard for short periods, do not ride the brake!!  Hope I'm not telling you stuff you already know.  Good luck!!

Yeah, your engine brake is more powerful than the OP's exhaust brake. 

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21 hours ago, jacwjames said:

Your system seems to acting differently then mine.

I leave my exhaust brake off until I need it.  When I turn it the transmission drops to 2nd gear, as long as I don't hit the accelerator it stays in 2nd gear.  If I turn on my cruise it disables the exhaust brake but if I start braking the exhaust brake kicks in. 

Not sure what the remedy may be, hopefully someone will chime in.

 

 

 

18 hours ago, Jemert said:

When my engine brake engages it downshifts to 4th if I'm going slow enough.  I've learned to hit the top of hills at the speed I want to descend.  That speed is generally between 45 and 50 because my coach will be approaching 2100 RPM in 4th at 50.  Generally my coach Jake brake will hold the coach under 50 on 90% of the descents I've encountered out West and on the way to and from Alaska.  If I have to brake on a descent I will brake relatively hard for a short period of time letting off the brake so they can cool.  When descending I generally have to accelerate periodically to maintain 45-50.  Most important points, speed at top of hill low and brake hard for short periods, do not ride the brake!!  Hope I'm not telling you stuff you already know.  Good luck!!

This is what mine does ...and I do what you are doing with braking ... So I must be doing what I need to be doing !!?? 
Do you ever get the brakes hot to the point of smelling them ?

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I have the Pac Brake system and I leave my exhaust brake off until I need it.  When I turn it on and let off the accelerator the transmission will drop to 2nd gear if my speed is low enough, and as long as I don't hit the accelerator it stays in 2nd gear.  My cruise is disabled if the  the exhaust brake is on.

Seems that Monaco had many ways of setting these up and there seems to be a lot of differences!

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4 hours ago, ukondew said:

This is what mine does ...and I do what you are doing with braking ... So I must be doing what I need to be doing !!?? 

Do you ever get the brakes hot to the point of smelling them ?

When I first bought the coach I smelled the brakes all the time.  I suspect that I was just not braking correctly.  Not sure what I do different now except I try to use the Jake brake most of the time.  If in stop and go traffic I turn it off, otherwise it is always on.  I take my foot off the accelerator way before I need to stop and let the Jake do the work.   I rarely smell them anymore.  I have property in the Mountains of TN and routinely drive up and down with numerous switchbacks.  Short answer, it was all me!  

 

Edited by Jemert
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I'm still trying to get my wife to use the jac brake correctly, she has a tendency to not turn it on until she's half way down a grade and having to use the brakes excessively to keep the coach from picking up speed.  I finely told her that she'd pay for the brake job when they got wore out and that got her attention. 

I don't leave my Jac Brake on all the time but not a hard to reach over and flip the switch.  It seemed that if I didn't have the right amount of pressure on the throttle it kept kicking on/off.  I do use the cruise control quite a bit. 

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2 hours ago, jacwjames said:

I'm still trying to get my wife to use the jac brake correctly, she has a tendency to not turn it on until she's half way down a grade and having to use the brakes excessively to keep the coach from picking up speed.  I finely told her that she'd pay for the brake job when they got wore out and that got her attention. 

I don't leave my Jac Brake on all the time but not a hard to reach over and flip the switch.  It seemed that if I didn't have the right amount of pressure on the throttle it kept kicking on/off.  I do use the cruise control quite a bit. 

Jim, my Jake turns off every time I touch the throttle.  I think it was designed to kick off when you accelerate.  Maybe I'm wrong but it seems to work well that way.  My coach is a little different in that I have to have the Jake on for the cruise control to work.  I suspect someone along the way has mis-wired it but I'm used to it now.  So I have to have to have the Jake on to use the cruise.

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I think your exhaust brake is normal although some coaches are programed different .

Country B described how mine works .

In my opinion speed is your problem I think you are driving down to fast .

Forget about the cars and think about how the semis approach the down hill on a mountain .  They stop check the brakes then start down slow , real slow .

I believe if you will stop or nearly stop at the crest and turn on the exhaust brake it will go into 2nd and stay there until the speed ( rpms ) btcome excessive .

Personally on a mountain pass that I'm not familiar with I start slow and stay there  .  These rigs are heavy and it's very hard to slow down when your speed gets high .

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On 12/14/2019 at 3:49 PM, daviraymo said:

 

Forget about the cars and think about how the semis approach the down hill on a mountain .  They stop check the brakes then start down slow , real slow .

 

Well, some do.

I've also traveled about 40 mi thru a mountain pass, passing a semi on the uphills, and him screaming past me on all the downgrades. And I'm probably averaging about 50 mph on these downgrades,  and he was passing me like I'm standing still!

 

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My Jake kicks it into 4th gear and stays there, if I want to keep the RPM below 2000, I have to keep stabbing the brakes over 50 mph.  Ben is right about most semis just passing me on the way down.  Must be ok with manual shift, obviously. Going south from Flagstaff is a long descent and I have seen trucks with red hot brakes and one with a wheel on fire taking an exit few miles after he passed me. Stabbing the brakes for a short time to slow down is what they teach for CDL air brake test that is mandatory in TX.

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If you slow down first and select a lower gear, you won't have to hit your brakes at all.  I can come down Teton Pass, 10% grade in 2nd or even first and touch my brakes, and that's with my 46,000# rig towing a 5500# truck.  My Jake is programmed to go to third, but on many steep descents it is necessary to manually shift down.

My Jake kicks it into 4th gear and stays there, if I want to keep the RPM below 2000, I have to keep stabbing the brakes over 50 mph.  Ben is right about most semis just passing me on the way down.  Must be ok with manual shift, obviously. Going south from Flagstaff is a long descent and I have seen trucks with red hot brakes and one with a wheel on fire taking an exit few miles after he passed me. Stabbing the brakes for a short time to slow down is what they teach for CDL air brake test that is mandatory in TX.

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When you engage the exhaust brake it doesn't downshift to second, it show's second on the dash, but doesn't go there. I leave my brake on all the time, if you want to run your cruise with the brake on, you can clip the #3 wire on the switch & route it through a floor switch. What I discovered was you can leave the switch in the on position with the floor switch off & your brake is on & the cruise works, if you want it back stock, just click the foot switch on & it works like normal.  As mentioned above, when I got down Monarch pass I start in 3rd gear at almost stopped & only have to stab the brakes once or twice all the way down. 05 Camelot 38 PDQ

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Foot off the throttle, press on Exhaust Brake and Allison will show a command to shift to 2nd gear, but will only shift down when speed allows.

The Allison can be programmed as to what gear it will try to select with the application of the Exhaust Brake.

My coach has an Exhaust Brake and not a Jake Brake, big difference, which it did have a Jake.

Safe travels to all.

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On 12/13/2019 at 8:05 AM, ukondew said:

My Exhaust  brake works when applied ... but even if I downshift manually the transmission will upshift when it hits a certain rpm ... then I apply my brakes to reduce the speed and keep the Exhaust brake on !
The brakes ..drums shoes , the entire system was replaced last year.
This has caused a few hair raising times and some hot brakes ..... Is there a problem with the system or am I doing something wrong ?
This is on a 2002 38 foot windsor with 62000 miles ,,, transmission has been serviced at the same times as brakes were done !
Thanks in advance !!

There has always been a LOT of confusion when people start describing the auxiliary braking system on their coach. There are two basic ones, an Exhaust Brake and an Engine Brake. Each one operates VERY differently.

Here is one link that explains the operation of each one.  https://tinyurl.com/wheg99l

From reading what you posted it sounds to me like your speed at the time you engage your Exhaust Brake is way TOO high. Exhaust Brakes are pretty useless with speeds at 55 mph and higher. If you are in 5th gear doing 55 and cresting a grade you are in for a "scary ride".

When I was Full-Time RVing, I had an over-weight coach (+300 lbs) and towing a 11,400 lb cargo trailer and traveling to Alaska every two years. I had to learn how to effectively use my Exhaust Brake quickly. First off because my ECM had been Flashed with the "Latching" program I was able to have my Exhaust Brake switch located on the drivers dash turned ON all the time even while using the Cruise Control. So that alleviated having to think about or look to see whether the switch was on or not. Next, I learned very quickly at what speed points my Allison MH3000 would up-shift to the next higher gear. That's when I discovered that the Exhaust Brake was totally useless in 5th gear when traveling 55 mph or higher.

So when I crested a hill I made sure I was in 4th gear or less doing about 45 mph or less. SO once I took my foot off of the fuel treadle, the Exhaust Brake would kick in but depending on the steepness of the grade the Exhaust Brake would either hold speed (not too often) or my speed would slowly climb. I also knew that once my speed reached 53 mph I needed to JAB the brakes hard to bring my speed back down 5-10 mph or more. If I had let the coach get to 54 mph or higher it would up-shift to 5th gear and we were off on the ride of a lifetime changing our underwear once reaching the bottom of the grade. If the grade was pretty steep, I would even crest the hill doing 35 mph or less as I knew that I would be jabbing the brakes even more.

The PacBrake Exhaust Brake that I currently have is the upgraded PRXB one which I had installed having the original one removed after returning from our first trip to Alaska. It works much better and I was happy with the changeover and increased exhaust compression.

So bottom-line, the Exhaust Brake works best in the lower speeds like 30-45 mph versus the higher ones 50+ mph.

Hope this helps!

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