agesilaus wrote: My understanding is that the 80% rule comes into play when you are hauling that load up a 8 or 9% grade in the Rockies. Plus the HP loss that comes with high altitude. I don't know how correct it is, but many of us have seen those people huffing and puffing away at 30 MPH on those western grades.
If you are just staying in the flatlands then you probably can pull up to your load limit and above.
BK
Nope, it not that.
My truck tows up to or slightly over its rating. Steepest Grade I have been on was 10%. The truck had no problem doing 35-40 up this 10% grade.
There were cars passing me, but so what, I am pulling a load, they are not.
My truck regularly tows up 9000-10000 foot passes, and has never seen the shop one day of its 8 year old life.
I am not sure how towing up a 10% grade at 35-40 mph is not safer than towing up a 10% grade at 70 mph with a trailer attached, for those that want to make that argument.
Guess I will keep waiting for imminent self destruction.
Here is what I read in Trailer Life I believe it was. They use the 80% rule to figure out big a trailer they can tow. They figure the other 20% is the cargo, passengers etc in the tow vehicle. So my truck can tow 12,300 lbs. That means I can tow a trailer that has a GVWR of 9840 and that will leave me with 2460 lbs of gear, gas and people in my truck.
Maybe this works for smaller TVs but I think I just demonstrated why it isn't a hard fast rule like some people think.
2008 F 250 FX4 4WD, V10, 4.10 Tow Command
35' 2007 Crossroads Cruiser CT32SB
Wonderful Wife and 3 small kids
Oh yeah, I love the "manufacturer won't honor the warranty" argument. So far, no one has told me of anyone THEY know that this happened to. Urban Legend at best....how is Ford, GM etc going to know what I was towing and how much it weighed. Give me a break people.
My truck tows up to or slightly over its rating. Steepest Grade I have been on was 10%. The truck had no problem doing 35-40 up this 10% grade.
There were cars passing me, but so what, I am pulling a load, they are not.
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Sure hope you weren't on an Interstate going 35 MPH!!!!!!!!!!!!!!
Bill B. (Michigan)
2007 Dodge Ram 2500 MegaCab CTD
2007 Jayco Eagle TT Model 322FKS
crappie_fisherman wrote: What 'limit' gets the 20% 'safety' factor reduction?
Joe.
Crappie_fisherman pretty much nailed the core question. When I posted this thread, I was assuming that each individual rating would be at the max. However, that is unlikly as each individual has differant expaectation when they hit the road. For example, in my case the only extra load in the TV is DW and 2 set of golf clubs....probably 250 lbs (including my excess over the 150 lb allowance) so we will never bust the TV GVWR. There are others who also like to allow 1500 lbs for water, firewood, and etc.
Personally, I believe in the engineered numbers. No manufacturer is going to fabricate the ratings. You need to set through design review meetings with legal to see just how consrvative specs really are.
Dick
2006 Jeep Liberty Turbo Diesel.....TV in Training
2005 Jeep GC 5.7L HEMI, 330 HP, 3.73 GR, 12,200 lb GCWR
2005 Jayco Jay Feather 25Z 5800 lb GVW, 4" lift
Equal-i-zer 10,000 lb hitch, Prodigy BC.
My truck tows up to or slightly over its rating. Steepest Grade I have been on was 10%. The truck had no problem doing 35-40 up this 10% grade.
There were cars passing me, but so what, I am pulling a load, they are not.
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Sure hope you weren't on an Interstate going 35 MPH!!!!!!!!!!!!!!
Most steep interstate grades have a slow lane. You are fully expected to go up at 35 mph. There are other lanes for the cars. and non towing vehicles. Actually 35 is pretty quick for some mountain grades. You'll be passing the trailertrucks.
You guys are missing the point of the "80% rule". No one is suggesting that you should operate at only 80% of your ratings. The ratings are the ratings and there is no need to build in an additional safety factor.
However, as Crappie Fisherman pointed out, the only way to know where you stand with the rating sis to weigh your rig. If a truck is rated to 10,000 lbs, that rating is based on an empty truck and one 150-lb driver. Every pound you add to that truck subtracts from that tow rating. For example, my truck is rated to tow 12,000 lbs, but the GCWR is 19,000. That means if I load the truck up to its 8600 GVWR, I can onkly tow 10,400 and still be withinh GCWR.
I think the "80% Rule" is a shortcut to weighing your rig and getting the specifics....If the tow rating is 10,000, then buy a rig with trailer with a GVWR of 8,000 and you;ll be fine. This adds a fluff factor for loading the truck, etc.
The "80% Rule" was designed to be a guideline for matching a trailer and truck based on the tow rating of the truck and the GVWR of the trailer. This left enought wiggle room to allow for loading the ruck as well.
People take this out of context and get their panties in a wad because they think their truck can't handle 100% of its ratings. Not the case.
My truck tows up to or slightly over its rating. Steepest Grade I have been on was 10%. The truck had no problem doing 35-40 up this 10% grade.
There were cars passing me, but so what, I am pulling a load, they are not.
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Sure hope you weren't on an Interstate going 35 MPH!!!!!!!!!!!!!!
The interstate is limited to 6% grades, you will not find a 10% grade on the interstate.
I am not sure how many 10% grades that you have ever been up, but believe me when I tell you that 35-40 MPH is plenty fast. Loaded Semi Trucks will be going slower than this, and Loaded UHAUL trucks will be crawling up at 5-10 MPH.
Guess all UHAUL type trucks should be taken off the road too. They are loaded way past 80% of their capacity, I can assure you. Inexperienced drivers are behind the wheel too.
Yet they don't crash or self destruct either? Hmmm?
You always hear people asking can vehicle X pull trailer Y?? IMHO many people know the answer. I think ratings are overated. Many things come into play when towing. Experience and time behind the wheel towing all kinds of trailers counts for a WHOLE lot. Trailer brakes, weight distribution, wheel base, etc. Conditions and the speed at which you are towing counts heavily as well. At the same time, People read these blogs and then look for that one person to say, yes, you'll be fine. That's a lot of responsibility that I don't want.
******BUT people are going to do what they are going to do. (And yes, I've been one of those people that towed over the limit of my vehicle.) I would tow the trailer again under the same conditions if I had to.
Tow what you want to tow if you feel comfortable. Just realize, you are the one responsible for those in your vehicle and around you. Good luck.
bluwtr49 wrote: I'm curious as to where this originated.
(snip)
Does anyone know the engineering behind this "rule"?
its a RV thing. never heard of it till I came on this web. We certainly don't see it in non RV web sites. If the commercial hauling industry (legal haulers), that use our LDTs, used the 80 percent recommendation that some RVers push they would all go broke or have a class 8 pulling a little 10k load. These folks run 100 percent of their limit all the time/have a excellent safety record/run their rigs for several hundred thousand miles. Which brings us to the misconception of some saying its safe by staying under a particular number or unsafe when going over. Bull dust. Being at or under the max or even the 80 percent limit does not mean we are safe. Granted some may feel safe towing with the 80 percent recommendation but many are comfortable towing the max or even over. Most RVers see overloaded truck/trailer combos on the road all the time and not just RVs. If being over was such a big safety issue why don't we see more accidents from overloading. I don't recommend anyone tow/haul over their tow vehicles weight limits BUT many do not know what their tow vehicles limits actually are. The 80 percent recommendation may make more sense for a small V8 or V6 or 4 cyl towing a tall heavy trailer in the mountains.
These trucks were engineered with commercial and non commercial hauling in mind. Certainly not just RVs as we've had pickup trucks long time before the RV industry was even thought about. Trucks are engineered/built for so many duty cycles. Those duty cycles are at 100 percent of max loads.
'03 2500 Dodge/Cummins HO 3.73 6 speed manual Jacobs
'97 Park Avanue 28' with two slides
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