|
|
07-04-2009, 11:29 AM
|
#11
|
Guest
|
Question about how to drive in or through our higher mountains:
If one's TrailManor, say a 3326K, when fully loaded for the road weighs in at about 5000 lbs, and one's truck, say a Ford F-150, has a towing rating of 7000 lbs. one would think there would be no problem towing in any elevation. Right? But I have heard that a 2000 lb. towing advantage may not be enough. The F-150 would slow down considerably towing the 3326 TrailManor in the mountains.
My question: under the scenario presented how should one tow, 1) let the truck slow down and try to enjoy the time of day and others passing you by, or 2) step on the gas (pedal to the metal) and force the truck to down shift and get the truck moving a bit faster?
How do you drive in the mountains?
Thanks.
|
|
|
07-04-2009, 01:39 PM
|
#12
|
Guest
|
Hi Tango, I have not pulled the TM thru the mountains yet, but have towed other things like ATV's and such up and over some of the hardest passes.
I have found that it seems to be easier on the TV and my self if i get in the slow lane and try and keep the revs in that 3,000 - 4,000 range, otherwise, you may over heat your TV. If your are towing ANYTHING, everyone thinks they need to pass you no matter how fast you are going. So make it easy on everyone and everything....take it easy.
When you start going down the other side, just put it in neutral and let 'er roll. j/k.....of course you want to use engine braking (a lower gear) as much as possible going down. If you can't, do yourself a favor and find a pull out and let the brakes cool down. Sounds simple, but you wouldn't believe all the people that use their brakes all the way down....and you can smell them when they go by you. Very dangerous!
Take your time in the mountains....it's a lot safer.
|
|
|
07-04-2009, 06:10 PM
|
#13
|
Guest
|
Thanks much for the info you provided. Wonder is there is anyone else who would care to share their experience in driving in and over high mountains?
|
|
|
07-04-2009, 06:18 PM
|
#14
|
TrailManor Master
Join Date: Jan 2022
Location: San Diego, California
Posts: 2,942
|
Quote:
Originally Posted by Tango286
Question about how to drive in or through our higher mountains:
If one's TrailManor, say a 3326K, when fully loaded for the road weighs in at about 5000 lbs, and one's truck, say a Ford F-150, has a towing rating of 7000 lbs. one would think there would be no problem towing in any elevation. Right? But I have heard that a 2000 lb. towing advantage may not be enough. The F-150 would slow down considerably towing the 3326 TrailManor in the mountains.
My question: under the scenario presented how should one tow, 1) let the truck slow down and try to enjoy the time of day and others passing you by, or 2) step on the gas (pedal to the metal) and force the truck to down shift and get the truck moving a bit faster?
How do you drive in the mountains?
Thanks.
|
Redhawk is right. You should look for a minimum of 60% of your engine's maximum RPM rating. Below that, horsepower and torque drop off dramatically. Try not to maintain over 80% of your max RPM over long periods of time. If your engine is downshifting, then up-shifting, lock it in the lower of the 2 gears. However, IMO the emphasis should be reversed (as I'm sure was his intent). Towing safety is 90% braking and 10% pulling. I don't think that very many people have ever been hurt by pulling up a mountain too slowly. It's all about coming down the other side.
Gearing of the vehicle means a lot. If the gears are too high, it's hard to get enough RPM out of the engine to have adequate power to pull mountains. When going down a gear, it often slows the vehicle to a point that getting enough air through the radiator, to accommodate the cooling required for the work that the engine is doing, becomes a problem. With most V6 engines, a 3.73 - 4.10 final drive gear ratio may be required for mountain driving. 3.42 may cause lugging and 3.08 is simply inadequate unless you have a BIG honking V-8.
Frankly, I feel that My S-10 PU may be over-rated for towing capacity because of down-hill grades. The tow rating (6400#) is nearly twice the dry weight of the vehicle (3221#). The truck has good size tires and some pretty hefty brakes. I'm not concerned about brake fading (the most dangerous aspect of towing). However, I am concerned that the vehicle may not be able to make an emergency stop going down a grade with a trailer pushing it due to the lack of weight of the TV.
There are so many things to be considered (even beyond manufacturers ratings). However, knowing the short-comings of your TV and letting that effect your driving habits can go a long way. A lot can be over-come (but not everything) by the way that you drive. Manufacturer's maximum ratings should be our MINIMUM requirements and only a starting point at looking at the entire towing experience.
__________________
TrailManor Elkmont
640W solar- 230AH LiFeP04 Battery
|
|
|
07-05-2009, 07:25 AM
|
#15
|
Guest
|
As mentioned in the above posts, there are two aspects to towing (or even just driving) in the mountains, especially those in the western U.S.: climbing and descending. Many of the factors apply equally to the eastern mountains, such as steep grades up and down, but the higher altitudes of the western mountains rob your engine of power and rob the air of its cooling power, that is, the air is thinner so cannot extract as much heat from cooling devices.
Wayne did a marvelous job of covering the uphill portion, especially talking about gearing, etc. One other item I'd like to mention is something I've only encountered once. My TV used to be an Explorer Sport Trac with the big V-6. On one road headed from Denver up to the Golden Gate State Park there was a very steep grade (well over 6%) on this narrow two lane road, and due to traffic I had to stop on this grade. Unfortunately, I couldn't get started again from the spot where I stopped -- there just wasn't enough oomph in the Sport Trac to do the job -- so I wound up backing down the hill a bit (thankfully not much over a hundred feet) to a bit more level spot where I could get rolling again. That's part of why I now have an F-150.
Both Wayne and John also have some good things to say about the downhill leg, but I'd add a little: the trailer pushes you. "let 'er roll" isn't always a good idea, except on the shallower slopes, since your speed may soon get out of hand, either exceeding what is safe for the tires/vehicle or what is safe for the curves(or both). In these cases, you may want to get slow enough to downshift (maybe more than one gear, depending on steepness, vehicle, road conditions, traffic, etc) to let engine braking reduce your braking needs to a few moments every little while, rather than almost continuous. You don't want the brakes to fade and you don't want them to catch fire.
Note that engine braking in a given gear won't be nearly as effective with the TM attached as it is without it, since the TM pushes hard going downhill. Do not let your vehicle build up a head of steam on the descent -- you may not be able to overcome it on the steeper slopes, especially those which have curves (nearly all of them). Be aware, too, that on many occasions the downhill grades may continue for several miles.
Finally, when there are warnings about steep grades for truckers, consider that those warnings also apply to you, if not quite to the same extent. That TM, combined with gravity, puts quite a load on your TV.
|
|
|
07-05-2009, 09:08 AM
|
#16
|
Guest
|
What is the combined TV / TM weight? Does it exceed the specs ( remember the TV weight is dry weight also so add in the passengers, and all the stuff in the bed. I have a 3/4 ton PU and a smaller trailer and when I had to make a sudden stop a few weeks ago, it was OK but certainly not as easy as I would have liked. If you get a spot with no traffic, try a stop so you know what to expect when you don't have a choice.
|
|
|
07-05-2009, 10:08 AM
|
#17
|
Guest
|
I concur with the above posts. I try to keep RPMs in the 3000-4000 range going up hill.
Going downhill, I get over to the right, keep plenty of space between me and the vehicle ahead, watch my speed very carefully, downshift on any steep grades and use my brakes sparingly.
Many years ago I lost my brakes to fade on a F-150 while taking my boat down a very long downgrade. Fortunately we were near the bottom but that was a scary experience. Never again!!!
|
|
|
07-05-2009, 12:30 PM
|
#18
|
TrailManor Master
Join Date: Jan 2022
Location: San Diego, California
Posts: 2,942
|
The reason that I used the 60%/80% formula in my post is so that those with the high RPM DOHC engines don't use the 3000-4000RPM figure.
If one has an engine that red-lines at 7000RPM they will want to keep a minimum RPM around 4000-4500 and a max sustained RPM around 5000 when climbing hills. This may even require grabbing a lower gear on some vehicles.
The reason that I mention this is that the torque ratings on a 7000RPM DOHC engine are drastically reduced at 3000-4000RPM and the driver will probably not be able to maintain speed. That engine should be able to be run in a lower gear and allowed to turn at a substantially higher RPM without concern of damaging the engine. DOHC engines develop most of their HP and torque at the higher end of the RPM curve.
Here's an interesting article on Torque/Hp:
http://auto.howstuffworks.com/horsepower1.htm
Here's a curve chart on a 7000RPM engine that describes what I was mentioning, the thing that must be recognized here is that this chart is on a racing engine. The torque curve on your engine will be a lot less in the lower RPM range, starting at closer to zero with a smooth curve, just above the HP curve then crossing over in about the same place:
On the other hand, if one has a diesel, they develop torque quite early and it may be best to keep them at a between 2500 and 3500RPM.
It's a good idea to look up the torque/HP curve chart on your TV so that you have a better understanding how what RPM range YOUR vehicle runs most efficiently at. Every engine model is designed with a different HP/torque curve. If you drive mountains, this information could be valuable to you.
One other tip on towing engines. Be sure to use synthetic oil in your engine and transmission. Synthetic oil disperses heat far better than petrol oils. This reduces heat build up and wear & tear on your engine. It's almost like adding a larger radiator to your vehicle.
When you are pulling a grade and you see the temp gage start to climb, that means that the engine is not releasing heat at a fast enough rate. As the moving parts of your engine heat up, they expand which causes more friction and less available HP. Think of your temp gage as a HP reduction gage. This means, the hotter that your engine gets, the more fuel that you have to give it (increased throttle) which, in turn, increases the heat even more. If the engine gets hot enough, it will actually "Seize", which means it will abruptly stop and may never turn again.
When mountain driving, keep an eye on the temp gage and don't let it get anywhere near the Red zone. If the gage is close, pull over, open the hood and let the engine cool down. If you haven't lost water, it's OK to leave it at idle for a few minutes before turning it off. NEVER open the radiator cap on a hot engine EVER. If you do, make sure that you are close to hospital a burn center because you may need it. This is very serious stuff. There have been cases where people have lost their entire face and/or received 3rd degree burns over their upper body. The Steam released from that radiator can be as high as 600 degrees. When the radiator cap is removed the entire cooling system may "Explode" all over you. That's roughly 3 gallons of boiling water and a huge amount of vaporous gas (steam), all released with a second or 2. That's not something to be messed with. The radiator cap should be cool enough to remove without using a rag for burn protection. If it isn't, leave it alone.
If you are using synthetic oil in your engine and trans, a 30 minute rest may be adequate. If you are using petrol based oil, the cooling process will be far longer, up to 2 hours. Never poor water on a hot engine. Although a spray bottle that delivers a mist can be very helpful. As the mist touches the hot surface, steam will be produces and the evaporation encourages heat release. This must be done with care because the steam can cause severe burns. If you have a 12V fan, that may help a lot. Don't run your battery down. If you can, use the battery from the camper. The thing that retains heat the longest is petrol based oils.
__________________
TrailManor Elkmont
640W solar- 230AH LiFeP04 Battery
|
|
|
07-06-2009, 03:51 PM
|
#19
|
Guest
|
Region factor?
Quote:
Originally Posted by harveyrv
Although I agree with Bill in theory....the reality of selecting ""WHERE do you plan to tow your trailer?" , may be a bit naive IMO........ How does the old saying go??...."The best laid plan of mice and men" or something like that..... .
I feel that the TV should be up to all challenges that it could possibly be challenged by. That is why vehicles are given ratings in the 1st place. You don't see "regional exceptions" on ratings.
|
Wayne, I fully understand what you're trying to say, and actually agree somewhat, but there is very valid point to Bill's comment about "where you plan to tow". I agree that if you are going out specifically to buy a TV for a TM, that you should "buy as big as you can afford", but "region" does come in to play, especially if you are like most and have a budget.
For example, it's at least a two day drive in any direction from New Orleans before you hit anything close to a "hill" much less a mountain. My wife and I could camp for years and never go over 200ft above sea level.
Do we eventually want to go to places like Yellowstone, Yosemite, etc,??... sure, but I can guarantee it won't be for at least 5-7yrs. We could use up a TV in that time, and then buy a larger one later when we do plan on more challenging trips.
There are also many who use RV's to simply get away on the weekends and rarely go more than a few hundred miles from home. If home is a place like Louisiana, then "grunt" is rarely needed, thus "region" does come into play.
Now if I was retired and going out today to buy that ultimate TV for the next 10yrs, and money is no object, then I would say to plan for the unexpected and buy a beast. I know I would.
|
|
|
07-07-2009, 09:13 AM
|
#20
|
Site Team
Join Date: Feb 2003
Location: The mountains of Scottsdale, AZ, and the beaches of Maine
Posts: 10,212
|
Quote:
That is why vehicles are given ratings in the 1st place. You don't see "regional exceptions" on ratings.
|
That's exactly the problem I was trying to lay out, Wayne. In my opinion, there SHOULD be regional exceptions (or at least regional advisories) on tow vehicle tow ratings. It doesn't take much thought to realize to realize that a single one-size-fits-all number cannot possibly cover all situations. But that is what the manufacturers give you. Again in my opinion, the tow vehicle manufacturers quote the best possible number (that is, the sea-level flatland number) because it maximizes their chance of selling you a vehicle. It is up to the buyer to realize that the flatland number won't apply when you are not in the flatlands.
I can guarantee you that a 3500-pound rated vehicle will not be adequate going up 8% grades at 8,000 feet as you approach a campground in Yosemite National Park in the high Sierras - or a campground at 10,000 feet in Colorado. I have gone both places with my TM and Explorer (rated 6800 pounds), and it was a long slow slog. [Full disclosure - I am unwilling to run the engine near red line for prolonged periods of time.] In spite of the fact that I had more than 2-to-1 margin (according to Ford), there were moments when I wasn't sure I was going to make it. Again in my opinion, there should be a regional advisiory, but since there is not, it is up to the owner to be smart about it.
Bill
|
|
|
|
|
Currently Active Users Viewing This Thread: 2 (0 members and 2 guests)
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads |
|
|
|
|
|
|
|
|
|
|
|
|
|