towing thru the mountains

[stanj]

We will take our long awaited journey next week across the US. I would like to ask for some pointers towing our 4500 lb jeep behind our 36 ft. gas ( 2003 workhorse chassis ) Motor home . How hard are the Mountains out west with a towed vehicle ? Rockies I 70 and norther California and I 80

Thanks in advance sj

[HighwayJunky]

We are in California now and drove from the east coast. Mountains and BIG hills are long and sometimes seems to go on forever. We tow a small car and are powered by a small diesel in a 37ft MH. No struggle for us at all but did go up some of those long hills at 35MPH. It was the best we could do. Suggest you increasing speeds as you look ahead and get a good running start up. It will save you some of the Passing gear/noise issues.

[Mile_High]

BigRabbitMan wrote:

Mile High wrote:

mama.sylvia wrote:
Finally cooled down enough for me to spend some time out in the Winnebago. My transmission is a PRND21. Still haven't seen anything like a tow/haul switch so I probably don't have it (but then I'm not likely to be towing). (Also found other valuable information, like the AC model info so I can get a replacement cover, and that the fridge is the original and doesn't work. lol)

No tow/haul on that classic 🙂 You have the GM Turbohydramatic 400 series 3 speed automatic. 3 speeds is all you get, and you best make sure it is in 1 before ascending a steep grade, because once it gets rolling over 30mph you will never get it back into 1st.

I think he meant Descending.

ah oops sorry. you are right. I can't even blame the phone autocorrect for that one 🙂

[BigRabbitMan]

Mile High wrote:

mama.sylvia wrote:
Finally cooled down enough for me to spend some time out in the Winnebago. My transmission is a PRND21. Still haven't seen anything like a tow/haul switch so I probably don't have it (but then I'm not likely to be towing). (Also found other valuable information, like the AC model info so I can get a replacement cover, and that the fridge is the original and doesn't work. lol)

No tow/haul on that classic 🙂 You have the GM Turbohydramatic 400 series 3 speed automatic. 3 speeds is all you get, and you best make sure it is in 1 before ascending a steep grade, because once it gets rolling over 30mph you will never get it back into 1st.

I think he meant Descending.

[Lwiddis]

Mike High, you are correct on the transmission...GM Turbohydramatic 400 series 3 speed automatic. While a previous owner could have replaced it, I've never heard of a "PRND12" aftermarket unit. Seems that would be shift selections available. See https://winnebagoind.com/resources/brochure/1988/88-Chieftain-bro.pdf

[Lwiddis]

"a tow/haul switch so I probably don't have it (but then I'm not likely to be towing"

Tow/haul isn't just for towing. It's very useful on a heavy vehicle such as a MH up and down hills. In fact when I'm not towing and climbing or descending the Sierras or Rockies it's "on" just for the Tahoe.

Chevy manual says: "The Tow/Haul Mode adjusts the transmission shift pattern to reduce shift cycling. This provides increased performance, vehicle control, and enhanced transmission and engine cooling when driving down steep hills or mountain grades, towing, or hauling heavy loads."

[Mile_High]

mama.sylvia wrote:
Finally cooled down enough for me to spend some time out in the Winnebago. My transmission is a PRND21. Still haven't seen anything like a tow/haul switch so I probably don't have it (but then I'm not likely to be towing). (Also found other valuable information, like the AC model info so I can get a replacement cover, and that the fridge is the original and doesn't work. lol)

No tow/haul on that classic 🙂 You have the GM Turbohydramatic 400 series 3 speed automatic. 3 speeds is all you get, and you best make sure it is in 1 before ascending a steep grade, because once it gets rolling over 30mph you will never get it back into 1st.

[mama_sylvia]

Finally cooled down enough for me to spend some time out in the Winnebago. My transmission is a PRND21. Still haven't seen anything like a tow/haul switch so I probably don't have it (but then I'm not likely to be towing). (Also found other valuable information, like the AC model info so I can get a replacement cover, and that the fridge is the original and doesn't work. lol)

[mama_sylvia]

I am starting to wonder if I will even need any special driving techniques for the stretch I'm thinking about, between Cheyenne and Laramie on I-80. Westbound, going up is very gradual, but down is roughly 5 miles of 5% grade. I have been up and down it hundreds of times so I know it quite well. No sharp turns, much less switchbacks. Driving a car, even going down I always have to apply gas just to keep up to the speed limit. Will a 27' class A Winnebago really be that much different? I also drove it frequently in a Fleetwood Jamboree class C (25'?) and never had a problem going either up or down, although I don't remember if I had to apply the gas pedal going down.

I'm planning a shakedown overnight at a state park about 15 miles away. Higher up in the mountains than our home location, but it's not steady up or down; the state road twists and turns and goes up and down. Again, I am VERY familiar with it so no surprises, and also drove it in the class C.

I'm sure I'll wind up on steeper roads that I'm not familiar with so I'm still following the thread. I also went looking for the Mountain West directory and discovered it's available in app form for $35. Has anyone used it? If it works as well as the book, it would sure be more convenient to take along.

[doxiemom11]

Some may thing this is all basic knowledge, but for us flatlanders we don't have to learn about this type of driving so it's all new to us.

[Mile_High]

I would agree. My 8.9 cummins does a whole lot better at engine braking than my pickup and 5er, but it still can overspeed. I stab or snub brake when necessary especially if I find I didn't quite get the right gear combination for the incline. You do have to drive the pass, it won't do it for you. I know some by heart, others I learn on.

[jeepfreak]

I see a lot of folks here seem to think if you leave it low gear that it will not pick up speed on the down hill. With the weight of the mh and toad you will continue pick up speed. Just completed a trip thru Az co , ut and went up and down many a 6-9 % grade with a 4 door jeep in tow. On the steep up hills found 1st gear at 3400 rpms was fine ( 20 mph) and down hills let get to about 35 to 40 mph and then hit the brakes and slowed to about 15 or 20 mph . Did not let the motor rev to over 4000 rpm. Wife really got annoyed at the roaring of the cooling fan on the up hills but I told that it's Avery good sound!

[bjbear]

mama.sylvia wrote:
...... I've never heard of stab braking, so please do explain it. If it turns out to be something I do know under another name, my feelings won't be hurt. I'd rather read 10 explanations of stuff I already know than miss the one that I don't.

I believe that it is "Snub" braking that people are usually referring to. Stab braking is something a little different.

Snub braking is applying your brakes intermittently. You apply the brakes reasonably hard and slow your speed by 5 mph in about 3 seconds. Then you allow your speed to increase back to where it was, then apply your brakes again to slow by 5 mph repeating as you continue down the hill. It has been determined that this is better than riding your brakes all the time mainly because when you drag the brakes continuously, not all brakes are carrying an equal load. The ones that are working the hardest, can overheat and damage the pads.

It is important to remember than Snub braking is only part of a good downhill technique and should not be relied on to control your speed totally.

There are a couple of good video at: Click Here and here: Click Here

To summarize, there are 3 basic steps:

Prepare - this involves insuring your equipment is working correctly and your brakes are set correctly. It also involves being aware of what lies ahead. How steep is the hill? How long are the down hill runs? What curves, turns, switchbacks are involved?
Control your speed going into the downhill section - Before you reach the downhill section, have your MH at the correct speed and in the correct gear. Basically this means being 1 gear lower than what you would use to climb the hill and having the engine rpm near governed speed to maximize your exhaust or Jake brake efficiency.
Snub Braking to maintain your speed - Use Snub braking to control your speed. Never let your speed rise above what you set when you entered the downhill section.

Note: This technique is applicable to both conventional and air brakes. If done correctly, Snub braking will not deplete a properly designed and maintained air system as the pressure will build up between brake applications.

[BigRabbitMan]

Yes, that is what it is BUT in my opinion if you have to do it a second time you better get into a lower gear as stab braking multiple times will still over heat the brakes and then away you go down the mountain.

[Lwiddis]

Monaco Monarch 2008 and newer have tow haul. I'll bet couple of years older do also. See page 13 https://library.rvusa.com/brochure/08Monarch.pdf