How steep a grade can I climb?

[paul102a3]

Thanks for all your input and advice.

I think I will go with plan B and keep the bus in Florida.

Paul

[Blacksheep]

Keep it on Florida and contract the rehab out! I'm always looking for more work!
Ace

[Len Silva]

Frankly, I don't think you will have any problem at all as far as power and torque with an 8-92.  I think I could have done it in my 4104.  Keep an eye on the tranny temperature just in case.

I do think that since you have to back one way or the other, I would back it up and drive it down. You'll have much better brakes and control going forward. Also, a lot easier if you change your mind halfway up.

I would have someone walking alongside with a radio to watch the approach and departure angles and to make sure you stay on the road.

Some of the guys on this board, faced with the problem of no room to turn around, would just build a turntable.

[Lin]

I had a short driveway with a similar grade that I brought my last bus, a Superior, up.  I do not know the gear ratio in first, but it topped out at about 5 mph at 3000 rpm.  I do not remember climbing being the problem.  I always imagined that that bus could go up a wall.  The problem I did have was dragging the back.  I got past that by putting railroad ties under the rear wheels when it was scrap time.   There was also no way to turn the bus around and it had to be backed down the same way.  This made to idea of using the bus rather distasteful, so it pretty much sat for a couple of years.

One thing about following the suggestion to back up the hill is that you will know right away if the rear is going to hit bottom.  You will also be able to be confident that if you got it up, you will be able to get it down.  Make sure your brakes and parking brakes are in great condition.  My parking brakes may have been a little out of adjustment, and the bus did begin to slip backward when, for a reason I can't remember, I applied the parking brakes and began to get out of the bus.

[tovinman]

The problem, from what you're telling me, might not be the hill so much as that transition from the hill partway up. The reason that a 40 foot trailer can make this transition and a 53 foot trailer cannot would be that the rear wheels of the tractor, when it reaches the level part, then swing up and into the bottom of the trailer. A 40-foot trailer would have a shorter wheelbase and thus the rear wheels of the trailer would reach the transition point before the approach angle became such that the tractor wheels would jam up under the trailer.

I used to have a very good picture explaining this point....one trucker decided that a shortcut through a field was a good idea. He could see the highway he wanted just ahead. What he couldn't see was the 60' embankment that led to the Canadian National Railway mainline. He got up the embankment, but the second he hit the tracks, the tractor leveled out and slammed the rear wheels up into the trailer floor, which was still at the 30-degree angle of the embankment. That was pretty much the end of both tractor and trailer.

A 40 foot bus would face a similar concern particularly since the ground clearance under your baggage bays would be pretty tight as it is
and you risk getting hung up right at the point the hill transitions to a flat. Once that drive axle leaves solid ground, you're not going to be going anywhere and even a tow truck may not be able to help you without inflicting way more damage than it ought to. An especially tricky situation would be if a uphill climb turned into a slightly downward angle the potential for hanging up the coach would be extremely high. Hooking a tow truck, parked downhill, to the engine cradle (the strongest part) would pull the rear end down, placing
extreme stress on the structure as it's simply not designed to handle such force.

I once really annoyed the manufacturers of the first low floor transit bus by demonstrating how easy it was to hang up their poor genius creation on a simple sidewalk cut. Front and rear wheels both, hanging in the air. Then again, I once invited the MCI Sales staff to coffee and donuts. When they got there, their coffee was waiting, along with their newest demonstrator equipped with rear wheel only traction control.

It was some time later that they discovered that the donuts they were being offered didn't come from a bakery. Four wheel ATC became standard VERY soon after.

Now, to be fair, the types of maneuvering that negated their TC system likely wouldn't have been done by anyone, ever, but in this business you never say never. Systems sometimes do unexpected things.

Some years ago an Aeroflot Boeing 767 crashed over northern Germany. The pilot had been fighting with a plane that seemed to want to fly any way but straight and level. After nearly an hour of fighting with the aircraft, it crashed.

Later on it was discovered that he had let his two children take turns sitting on his lap and very slowly turning the wheel to the left, then to the right, while in autopilot. What the pilots, and Boeing, didn't know was that this act caused parts of the autopilot to disengage without offering any warning to the pilots. The pilot ended up fighting with the autopilot, which he thought was in fact fully off, while the autopilot kept correcting against the pilots' input, and eventually it caused a condition in which the aircraft could not fly.

On the other hand, a man sued Winnebago and won, after the brand new Winnebago he was driving ran off the road and crashed after he had gotten up out of the drivers' seat to fix himself a cup of coffee. He won the case because, as he stated, the owners manual didn't specifically state that you could not do this.

In other words, if you have reason to question whether something is safe, err on the side of caution, always.

There is in fact a way to determine whether your coach has enough ground clearance to make it over any transition. Simply measure the wheelbase (the distance from the center of the front wheel to the center of the drive axle.  Mark this down. Divide that figure in half.

Then get a surveyor to plot the elevation of the hill at this "half" distance below the crest of the hill, and then the elevation at this "half" distance forward of the crown. Then measure the height between the ground and the bottom of the baggage bays (on level ground) at the halfway point between axles. If this measurement is less than half the difference between both survey measurements, you're very likely going to hang up.


 


































 

[buswarrior]

toviman....

this all sounds so familiar...

we got some history or is this just a coincidence?

happy coaching!
buswarrior

[John316]

Tovinman,

That sure sounds interesting. Where did you use to work, or get all of this knowledge. I am just curious, because that was a fascinating post.

God bless,

John

[gyrocrasher]

Tovinman said: "On the other hand, a man sued Winnebago and won, after the brand new Winnebago he was driving ran off the road and crashed after he had gotten up out of the drivers' seat to fix himself a cup of coffee. He won the case because, as he stated, the owners manual didn't specifically state that you could not do this."

That one's been circulating for YEARS.   http://www.snopes.com/autos/techno/cruise.asp

PS scroll to near the bottom.   Mitch

[buswarrior]

Yup, from his other posts today, awfully "knowledgeable" for a new arrival...

I've seen a guy just like this with pretty much the same name in action elsewhere on the internet.

Appears to know lots, important details that real experience would have taught are suspiciously missing.

Strings folks along who know less and can fire up a real good flame war.

Standby, it'll get interesting!

happy coaching!
buswarrior

[John316]

Give him a chance, guys. It may be that he just has a wealth of knowledge (I know, I know, Jimgegetie??? is still very fresh in my mind). Lets just see if he pans out, or not. Time will tell. With Jim it was sooner, as opposed to latter...

JMT

God bless,

John

[buswarrior]

John,

I would ordinarily be with you on this, but after further checking, this guy is a known entity, and not a busnut as we know one.

He is known at other bus related sites as a spinner of yarns, using generalities, half truths and falsifications that are enticing to the novice, but quite wrong and/or offending to subject matter experts.

Observe the challenges to his posts on other threads.

He is of no help to us.

happy coaching!
buswarrior

[Hartley]

Oh..Boy..




Check the factory specs on approach and departure angles for your Bus...
That will answer your questions usually.

[John316]

John,

I would ordinarily be with you on this, but after further checking, this guy is a known entity, and not a busnut as we know one.
Observe the challenges to his posts on other threads.

He is of no help to us.

happy coaching!
buswarrior

Thanks BW. Point well taken. And just because you didn't agree with me, I won't leave the board . I appreciate it, and I think that I am agreeing with you now...

God bless,

John