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 3/27/2010 9:18 PM
 

My wife and I just purchased our first motorhome, a Coachman C class. I have been reading

this forum for some time, and can't tell you how much I have learned. However, I am confused

about information on driving in the mountains. On several threads it has been stated that you

should ascend and descend in lower gears. Does this pretain to automatic transmissions, or

are you only referring to standard transmissions? If automatic also, do I shift to lower gear

before starting down? Thanks


Randy and Evelyn. 2002 Adventurer 35U,Triton V10. 2009 Saturn Vue. Plus Buddy the superdog.
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 3/28/2010 12:15 AM
 
 Modified By slabman  on 3/27/2010 11:16:51 PM

Downshifting would apply to both types of transmissions when ascending AND descending. You should engage the lower gear BEFORE needing to, in order to keep the vehicle under control. If you do it too late whilst going downhill, you may not be as successful in controlling your speed without also having to use your brakes. Also, remember to always pump those brakes when additional braking is needed to allow for cooling.

When going uphill the tranny will downshift when needed, however, you can sometimes maintain higher speeds/rpm if you engage the lower gear earlier. However, I don't think this is nearly as important as downshifting early when going downhill.


Bob J. from TX 2014 Newmar Essex 4544 2007 Lexus LX 470 Toad
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 3/28/2010 12:48 AM
 

randybst - Most RVs have automatic transmissions, so I'm assuming yours does also. My RV is built on a Ford chassis (F53) and the transmission (E40D) is limited as to when it can downshift. On this particular chassis the tranny won't downshift to first gear unless the speed is less than 30 mph, regardless of what gear you've manually selected. This means if you start down a steep slope in second gear and the brakes can't slow you below 30 mph your tranny won't be able to shift into first gear until you get below 30. Thank goodness a fellow RVer warned us to shift to first gear before descending into Death Valley from Lone Pine, because without that advice I'm not sure how we'd have gotten to first gear to assist the brakes on that very steep and lengthy decent. Diesels are a different animal, so this advice only pertains to gassers. Good luck. - Dave

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 3/29/2010 8:39 PM
 
randybst- after downshifting to a lower gear if you need additional braking apply firm pressure to slow the speed down to about 5 mph slower then you want, make sure to release the brake completly then when you reach your normal safe speed reapply the brakes again same as the first time. if you tow a car be sure to get an auxlilary brake for the car.

mike
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 3/29/2010 9:21 PM
 

Randy, is the Coachmen a new coach? On a Ford chassis? If so, you have a "tow/haul" button on the end of your shift lever. When descending a hill/mountain, push that button before you start down. When brake pedal is pushed the transmission will automatically shift into a lower gear, from 5th through 4th, 3rd, and 2nd, and, if needed, into 1st. The transmission is electronic and will not shift into a gear that will harm it, even though the engine will really rev up when a new gear is reached. Use the brakes to slow the coach to a comfortable speed by "stabbing" and releasing the pedal as has been well explained previously.

Before attempting any steep mountain grades, try the process out on some hills. Once you become accustomed to the process (and the noise as the engine revs) you will gain confidence in the engine, transmission, and brakes on the Ford chassis.

The owner's manual describes the "tow/haul" feature. My coach even came with a DVD that demonstrated the process.


Dutch '07 Allegro Bay 34' '09 Honda Fit Sport Whatever hits the fan will not be distributed evenly
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 3/30/2010 5:07 PM
 
First, thanks to all who answered. Dutch, no, it is a '98 coachman on a Ford chassis. At

this time I am having the brakes redone. I told the man working on it I wanted everything

replaced, discs, pads, hardware, etc. I don't want to get out there and wonder what's under

there. I like the idea of starting off with short hills. Living in Florida, with relatives in Texas

you forget how to drive up and down. Perhaps a trip to north Georgia first. Again, thanks to

all who responded.


Randy and Evelyn. 2002 Adventurer 35U,Triton V10. 2009 Saturn Vue. Plus Buddy the superdog.
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 6/24/2014 8:12 AM
 

A good rule of thumb is to go down the hill slower than you climbed it in 1 or 2 gears lower than you used going up.

I was a trainer for long haul truck drivers and here is my mandatory advice to every trainee.....

IF YOU HAVE TO USE YOUR BRAKES TO SLOW THE RIG YOUR GOING TO FAST

reason= if you use up your brakes your either going to have to use the truck escape ramp (destroying your rig) or your going to be dead

YOU WILL ONLY GO DOWN A HILL TO FAST ONE TIME (BECAUSE YOU WILL NOT BE ALIVE TO TRY IT AGAIN)

Now on big rigs you have a Jake brake ... my reasoning is that if you go down without using your brakes if something fails like the JAKE (engine brake) or the engine dies then you still have all your brakes to stop you..... however if you heat them half way to failure point you won't know it and if there is a failure YOUR DEAD OR YOU WILL BE CLEANING YOUR DRAWERS AT THE LEAST

While your learning your new rig stop at the top and bottom of every grade and walk around your rig checking for brake smell and any signs of heating including feeling your tires and rims......feel your rims carefully because they might burn your hand..... motorhomes and travel trailers should for safety follow the speed limits placed on trucks when doing downgrades .... I personally suggest going slower than the recommended truck speeds... at least until you know your rig And never never never exceed those limits..... Always stop and check your brakes at truck brake check areas

To aid in slowing your rig turn on all engine loads you can such as the air conditioning even in winter..... On a big truck turning on the a/c as well as the engine fan (they usually have a manual electric fan clutch) will save your brakes and hold you back a noticeable amount. Just like turning off your a/c when climbing a Hill Will allow more climbing power turning it on going down will pull the engine rpm Down

Following the things I have advised will keep you alive and will save you money and time on brake jobs

Like I said above you only go down a hill to fast ONE TIME

KEEP YOUR SELF AND YOUR FAMILY SAFE AS WELL AS ALL THE OTHER DRIVERS YOU MIGHT RUN OVER IF IT GETS AWAY FROM YOU

if your rig has air brakes and your using your brakes going down you could suffer brake fade and your dead or you could use up your braking air and your dead..... hills are not to be taken lightly

While your learning your rig pay close attention to the signs telling you the grade percentage and the length of that grade.... If it don't tell you how long the grade is assume its the longest......

And my last bit of advice .... Once you learn your rig don't get brave because engines are known to fail on the down hill from the work they just did to climb that same hill..... with air brakes you only havea limited amount of air to stop you.... On rigs with conventional brakes if the engine dies you lose your power assist ... either way you will be fighting to stop .... If the engine fails (and even new engines die sometimes) put on your emergency flashers and stop the rig immediately As fast as you can safely stop getting as far right as possible .... even if the road doesn't have a wide shoulder

..... HILLS DO KILL

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 6/24/2014 9:12 AM
 

I might be going overboard on this but it's important

Even if your brakes are brand new and the best available if you heat them up you will still suffer brake fade and once they begin fading your in serious trouble.

Brake fade occurs from heat it can even happen In the coldest weather

When your brakes heat up the pads begin releasing gasses ..... This happens between the hot pad and the hot drum or disk.....when those gasses begin releasing it creates a seperation between the drum or disk very much like when water causes hydro planing between your tires and the road on a rainy day....... So the pads begin gassing which means you will have to apply more braking power to keep from speeding up... applying more braking power will cause the brakes to gas even more requiring more braking force.... it is a vicious circle with no way out except to stop with all the braking force you can apply...... And to hope that the gassing does not go up faster than you can stop.... brake face once it starts gets worse really really really really fast

IF YOU EVER EXPERIENCE BRAKE FADE YOUR ONLY OPTION IS TO PANIC STOP AS FAST AS YOU POSSIBLY CAN without crashing and once you have stopped stay behind the wheel with the brakes applied fully ..... watch your rear view mirrors to see if your wheels are smoking and watch for signs of fire ....... stay behind the wheel with yourfoot on the brakes until your brakes have cooled...... To many times people apply the parking brake and get out to only to find that the parking brake does not hold ..... putting the rig in Park is good to do with auto trans and if you have someone with you have them chock as many wheels as you possible is an excellent thing to do set the park brake and wait to be sure they are holding b4 you get out..... This way if your brakes catch fire you can leave the rig with a good chance it will not roll away

If your brakes Do catch fire use your fire extinguisher in short bursts to just kill the flames then wait they will most likely flame again Then short burst to kill the flames again....... You should not use all of the extinguisher in one blast because only time will dissipate the heat and the flames will come back a few times b4 they cool enough your fire extinguisher will not cool the brakes it will only put out the fire and the fire will probably come back

Putting water on the wheels will help cool the brakes but will not put out brake fire until the cooling is enough .... use the extinguisher to kill flames and water to cool while there are no flames......

If you have those tiny fire extinguishers replace them with large ones ..... The tiny ones won't be enough ..... And it's good to keep one near the driver one near the entry door one in your outside access to the fridge and one in the propane access area... If ever You have brake fade and your brakes are smoking get stopped chocked and get your fire extinguishers ready then get water ready too ..... brake fires once they start take time to cool.....

If you try to milk your brakes when they fade hoping they will cool or last to the bottom of the hill they will get ahead of you and they will do that fast

Sorry to get so long winded but it's a serious topic and I have seen trucks use escape ramps I have seen Brake fires and I have experienced personally brake fade gettjng ahead of me because I did not stop immediately when I first felt it.....

Hills can kill

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