Comparing tow vehicle suitability to engine mods.....
Posted: Sun Nov 21, 2004 8:15 pm
Ken L et. al.
This issue is complicated enough...... mixing apples and oranges (Tow vehicle suitability and mac engine size increases) here is NOT going to provide many more individuals greater insight.
There are many design issues associated with towing.
Hitches have only a few Specified DOT controlled issues and specifications......
And for the vehicles........
some specifications from
Consumer Guide
2005 Endeavor
Torque (lb-ft) @ rpm 255 @ 3750
Curb Weight, lbs. 4079
\Horsepower @ rpm 215 @ 5000
225-hp 3.8-liter V6 and a 4-speed automatic transmission with manual shift gate. All offer front-wheel drive or all-wheel drive that lacks low-range gearing and is not intended for severe off-roading. (Their statement not mine)
235/65R17 tires
even within this page two separate horsepower max's are given for the Endeavor.
vs
for a an F150
Size, liters/cu. in ..... 4.6/281 ....... 5.4/330
Horsepower @ rpm 231 @ 4750 300 @ 5000
Torque (lb-ft) @ rpm 293 @ 3500 365 @ 3750
Model............. reg......LB....5.5B....6.5B.....extB...crew
Wheelbase, in. 125.8 144.5 132.5 144.4 163.0 138.5
Overall Length, in. 211.5 230.1 218.0 229.8 248.5 224.0
Overall Width, in. 78.9 78.9 78.9 78.9 78.9 78.9
Overall Height, in. 72.8 72.9 73.1 73.1 73.1 73.1
Curb Weight, lbs. 4788 4908 4993 5115 5451
vs toureg
Engines dohc V6 dohc V8 Turbodiesel sohc V10
Size, liters/cu. in 3.2/195 4.2/252 4.9/300
Horsepower @ rpm 220 @ 5400 310 @ 6200 310 @ 3750
Torque (lb-ft) @ rpm 225 @ 3200 302 @ 3000 553 @ 2000
Wheelbase, in. 112.4
Overall Length, in. 187.2
Overall Width, in. 75.9
Overall Height, in. 68.0
Curb Weight, lbs. 5086
Now with the variances of tire contact patch area, frame stiffness, vehicle torsional rigidity, Suspension flex, number of axles on the trailer, loading differences....Weight distribution, Distance from the hitch point to the rear axle etc....all affecting towing ability, and, despite claims to the otherwise
)A shorter wheelbase vehicle has less lateral stability than the same weight of vehicle with a longer wheelbase.
But most importantly, and strangely enough, few are noticing what Moe is trying to put across here.... A better performing tow vehicle will have a stiffer frame, longer wheelbase, greater load rating, more torque, stronger components..... preferrably vehicle tire contact area greater than the trailer tire contact area.. tow vehicle weight greater than trailer weight...etc.
1) Towing with a vehicle lighter than trailer on a coventional 2" round ball hitch is not the Best Practice, and a sway control hitch will improve the ride and handling, but does not remove all of the problem
2) An unloaded 40 ft trailer on a tractor trailer rig passing you at 70 mph vs your 60 mph, separated by 3 ft. or less is going to move and sway a Mac and trailer. Comments like " The trailer does not sway and the vehicle handles great" are at best a triumph of hope over reality). The laws of physics are not rescinded by kind words....
3) Tow Vehicle differential gearing and engine cooling are critical.
(IS someone implying here that a Toureg , endeavor or other similiar size and weight vehicle is going to perform the same as a full size rig) I deal with contractors that haul trailers loaded all the time......those rigs are not light.. and I cant say that they have been beating down VW factory dealership doors for the new fantastic wunderkind tow vehicle.
At best the toureg is not the tow vehicle the 2500/250 truck is.,
It does look to be slightly less than a 1500/150 truck for handling and performance.
and I think all would agree a 1500/150 truck is sufficient for a mac.
is it enough for a lightly loaded mac.....towed and trailer vehicle weight the same....... perhaps.....? After my test drive yesterday..... I think I still prefer a 2500/250 for handling and performance
now I am also sure that I do not have the most +4,000 lb trailer towing experience on this forum, (i am sure 70,000 miles is not enough to take that title) But there are no vehicles that tow that weight of trailer....., (My average non horse trailer weight is a little over 5400, ) with more stability than the long wheelbase full size rigid frame offerings from the american big 3 and now toyota and nissan. (including of course their culture coached suburbans, Expeditions, Excursions, Invasions.......Annnihiliations......etc..... ( In fact I keep my beast just because it is hard to justify getting rid of a perfectly good handling low cost easy to maintain (Alright.. i see all the old dead ford jokes coming... so save them) F250/460.
Most people tow rarely.....
as a function of the total miles on a given vehicle the full size rigs are better suited to towing. And yes I freely admit (here in front of god and everybody) I have used a little Mazda b2000 with a class 2 hitch to haul a mac for a couple of hundered miles when I was stuck in the wrong place without my regular tow vehicle....... (3000 lb truck with 88hp) But it is not as safe as towing with the F-250
And I will guarantee that you too will be responsible if your overloaded trailer, or overloaded tow vehicle exceeds either DOT, Vehicle manufacturer, hitch manufacturer, or tire manufacturer specifications. And you will most likely find your vaulted insurance useless if the insurance company finds you willfully violated those specfications and operated contrary to them. And as stated elsewhere.......that assignment of some of the blame to you, is far beyond most peoples catastrophic liability insurance is going to pay out.
And most likely since you own a mac, Ya aint in rich man's tax bracket where you can drop 2-4 million for an at fault claim.
And as far as boat recommended horsepower..... Because of the way The law in the united states has developed.......This is not the same for boats. BIA, CG, NMMA, and other organizations with conflicting certs actually have less control over what size engine or abilities are in any boat. Futhermore, the certificaiton process for marine equipment is still within the reach of the average backyard hobbyist. Write a few papers, document a few tests...... and your insurabilty would be as good as most manufacturers.....( I speak from experience here, several of my boats lost warranty coverage by the manufacturer going out of business). And I have found that for all but the largest or most exotic boat manufacturers. the structural modeling and analysis of their boats... is not very in depth..
and now to get to the crux of my lament
I have read or corresponded with many many people who have endeavored to upgrade the engine size on a mac, has recognized the need for transom upgrades and hull improvements, possible trailer modifications, fuel system and steering modifications and many other elements that need to be addressed in a horsepower/weight upgrade. I myself have concenterated on analyzing and providing interior hull structural modifications to stiffen the transom and hull, modifying the trailer, etc prior to installing an engine upgrade.
Now
If you want to compare here the apples to oranges....
Are the toureg and Endeavor, explorer, caravan owners out their considering what has to be done to their vehicles to provide for safer towing and handling. Are any of them contemplating installation of New frame Rails, suspension lowering and modifications, Differential or transmission gearing changes.larger springs, hi performance oil cooling systems, changes to tires and wheels..... So that their vehicles can tow 100,000 miles safely??. (Items that are already present in vehicles designed to tow large loads from the factory).
So I think engine upgrades are being addressed here on the forum correctly with respect to the actual design criteria, physical and structural limits of the materials and processes. And I do think it is possible to provide many modifications to improve the towing ability of many vehicles.....
I doubt most people are going to go do what would need to be done to convert a 50,000 dollar toureg they are still making payments on, into a long wheelbase, rwd, stiffer suspension towing vehicle. Especially since those that would typically have the aptitude, inclination and ability to do such a thing themself would probably have the techinal background and abilities to recognize the limits of each platform, and would most probably modify a more appropriate vehicle for towing.
SO I can understand the tone in writings of many of the forum's participants, both for and against any given vehicle and lest anyone feel that I am lambasting VW or mitsubishi or other midsize (Roger did put out ad copy with a Taurus towing, and after crawling under a Toureg yesterday, I feel that vehicle is better suited than the taurus) that is not the case.. ( I still own a VW and cherish that vehicle considerably).
But for considerably less money than a toureg, one could obtain a crewcab shortbed pickup, with a V8 engine, and obtain mileage in the 18-20 mpg range and still tow safely. and still have the 125" +wheel base and 5200 vehicle weight.
Because the toureg type of vehicle has considerable power at speed, (at least the mostly unavailable deisel V10, only 1500 are going to be allowed in this year, so unless you want to pay 58K, your going to get a V8 gas) the tendency is to think that it is an all perfect multiuse vehicle. But there are tradeoffs.......and the touregs profile, weight distribution, braking ability, resistance to lateral pressure, do not indicate better highway speed towing than a standard size pickup.
On the flat, fewer than 4,000 miles a year, wide roads, and little traffic passing you at 75-80 mph, keeping th mac weight below 4,000, you can probably get by with many smaller midsize vehicles...... (Which is probably 95% of most mac owners) just dont expect it to last as long towing as a full size towing rig tho.
Maybe a better title for this thread would have been ..something like..
"minimum safe tow vehicle for a 4500 llb mac and trailer for towing less than 4,000 miles a year and never up a 6 % grade more than 2 miles long.) and having the mechanicals last for 100,000 miles"
This issue is complicated enough...... mixing apples and oranges (Tow vehicle suitability and mac engine size increases) here is NOT going to provide many more individuals greater insight.
There are many design issues associated with towing.
Hitches have only a few Specified DOT controlled issues and specifications......
And for the vehicles........
some specifications from
Consumer Guide
2005 Endeavor
Torque (lb-ft) @ rpm 255 @ 3750
Curb Weight, lbs. 4079
\Horsepower @ rpm 215 @ 5000
225-hp 3.8-liter V6 and a 4-speed automatic transmission with manual shift gate. All offer front-wheel drive or all-wheel drive that lacks low-range gearing and is not intended for severe off-roading. (Their statement not mine)
235/65R17 tires
even within this page two separate horsepower max's are given for the Endeavor.
vs
for a an F150
Size, liters/cu. in ..... 4.6/281 ....... 5.4/330
Horsepower @ rpm 231 @ 4750 300 @ 5000
Torque (lb-ft) @ rpm 293 @ 3500 365 @ 3750
Model............. reg......LB....5.5B....6.5B.....extB...crew
Wheelbase, in. 125.8 144.5 132.5 144.4 163.0 138.5
Overall Length, in. 211.5 230.1 218.0 229.8 248.5 224.0
Overall Width, in. 78.9 78.9 78.9 78.9 78.9 78.9
Overall Height, in. 72.8 72.9 73.1 73.1 73.1 73.1
Curb Weight, lbs. 4788 4908 4993 5115 5451
vs toureg
Engines dohc V6 dohc V8 Turbodiesel sohc V10
Size, liters/cu. in 3.2/195 4.2/252 4.9/300
Horsepower @ rpm 220 @ 5400 310 @ 6200 310 @ 3750
Torque (lb-ft) @ rpm 225 @ 3200 302 @ 3000 553 @ 2000
Wheelbase, in. 112.4
Overall Length, in. 187.2
Overall Width, in. 75.9
Overall Height, in. 68.0
Curb Weight, lbs. 5086
Now with the variances of tire contact patch area, frame stiffness, vehicle torsional rigidity, Suspension flex, number of axles on the trailer, loading differences....Weight distribution, Distance from the hitch point to the rear axle etc....all affecting towing ability, and, despite claims to the otherwise
)A shorter wheelbase vehicle has less lateral stability than the same weight of vehicle with a longer wheelbase.
But most importantly, and strangely enough, few are noticing what Moe is trying to put across here.... A better performing tow vehicle will have a stiffer frame, longer wheelbase, greater load rating, more torque, stronger components..... preferrably vehicle tire contact area greater than the trailer tire contact area.. tow vehicle weight greater than trailer weight...etc.
1) Towing with a vehicle lighter than trailer on a coventional 2" round ball hitch is not the Best Practice, and a sway control hitch will improve the ride and handling, but does not remove all of the problem
2) An unloaded 40 ft trailer on a tractor trailer rig passing you at 70 mph vs your 60 mph, separated by 3 ft. or less is going to move and sway a Mac and trailer. Comments like " The trailer does not sway and the vehicle handles great" are at best a triumph of hope over reality). The laws of physics are not rescinded by kind words....
3) Tow Vehicle differential gearing and engine cooling are critical.
(IS someone implying here that a Toureg , endeavor or other similiar size and weight vehicle is going to perform the same as a full size rig) I deal with contractors that haul trailers loaded all the time......those rigs are not light.. and I cant say that they have been beating down VW factory dealership doors for the new fantastic wunderkind tow vehicle.
At best the toureg is not the tow vehicle the 2500/250 truck is.,
It does look to be slightly less than a 1500/150 truck for handling and performance.
and I think all would agree a 1500/150 truck is sufficient for a mac.
is it enough for a lightly loaded mac.....towed and trailer vehicle weight the same....... perhaps.....? After my test drive yesterday..... I think I still prefer a 2500/250 for handling and performance
now I am also sure that I do not have the most +4,000 lb trailer towing experience on this forum, (i am sure 70,000 miles is not enough to take that title) But there are no vehicles that tow that weight of trailer....., (My average non horse trailer weight is a little over 5400, ) with more stability than the long wheelbase full size rigid frame offerings from the american big 3 and now toyota and nissan. (including of course their culture coached suburbans, Expeditions, Excursions, Invasions.......Annnihiliations......etc..... ( In fact I keep my beast just because it is hard to justify getting rid of a perfectly good handling low cost easy to maintain (Alright.. i see all the old dead ford jokes coming... so save them) F250/460.
Most people tow rarely.....
as a function of the total miles on a given vehicle the full size rigs are better suited to towing. And yes I freely admit (here in front of god and everybody) I have used a little Mazda b2000 with a class 2 hitch to haul a mac for a couple of hundered miles when I was stuck in the wrong place without my regular tow vehicle....... (3000 lb truck with 88hp) But it is not as safe as towing with the F-250
And I will guarantee that you too will be responsible if your overloaded trailer, or overloaded tow vehicle exceeds either DOT, Vehicle manufacturer, hitch manufacturer, or tire manufacturer specifications. And you will most likely find your vaulted insurance useless if the insurance company finds you willfully violated those specfications and operated contrary to them. And as stated elsewhere.......that assignment of some of the blame to you, is far beyond most peoples catastrophic liability insurance is going to pay out.
And most likely since you own a mac, Ya aint in rich man's tax bracket where you can drop 2-4 million for an at fault claim.
And as far as boat recommended horsepower..... Because of the way The law in the united states has developed.......This is not the same for boats. BIA, CG, NMMA, and other organizations with conflicting certs actually have less control over what size engine or abilities are in any boat. Futhermore, the certificaiton process for marine equipment is still within the reach of the average backyard hobbyist. Write a few papers, document a few tests...... and your insurabilty would be as good as most manufacturers.....( I speak from experience here, several of my boats lost warranty coverage by the manufacturer going out of business). And I have found that for all but the largest or most exotic boat manufacturers. the structural modeling and analysis of their boats... is not very in depth..
and now to get to the crux of my lament
I have read or corresponded with many many people who have endeavored to upgrade the engine size on a mac, has recognized the need for transom upgrades and hull improvements, possible trailer modifications, fuel system and steering modifications and many other elements that need to be addressed in a horsepower/weight upgrade. I myself have concenterated on analyzing and providing interior hull structural modifications to stiffen the transom and hull, modifying the trailer, etc prior to installing an engine upgrade.
Now
If you want to compare here the apples to oranges....
Are the toureg and Endeavor, explorer, caravan owners out their considering what has to be done to their vehicles to provide for safer towing and handling. Are any of them contemplating installation of New frame Rails, suspension lowering and modifications, Differential or transmission gearing changes.larger springs, hi performance oil cooling systems, changes to tires and wheels..... So that their vehicles can tow 100,000 miles safely??. (Items that are already present in vehicles designed to tow large loads from the factory).
So I think engine upgrades are being addressed here on the forum correctly with respect to the actual design criteria, physical and structural limits of the materials and processes. And I do think it is possible to provide many modifications to improve the towing ability of many vehicles.....
I doubt most people are going to go do what would need to be done to convert a 50,000 dollar toureg they are still making payments on, into a long wheelbase, rwd, stiffer suspension towing vehicle. Especially since those that would typically have the aptitude, inclination and ability to do such a thing themself would probably have the techinal background and abilities to recognize the limits of each platform, and would most probably modify a more appropriate vehicle for towing.
SO I can understand the tone in writings of many of the forum's participants, both for and against any given vehicle and lest anyone feel that I am lambasting VW or mitsubishi or other midsize (Roger did put out ad copy with a Taurus towing, and after crawling under a Toureg yesterday, I feel that vehicle is better suited than the taurus) that is not the case.. ( I still own a VW and cherish that vehicle considerably).
But for considerably less money than a toureg, one could obtain a crewcab shortbed pickup, with a V8 engine, and obtain mileage in the 18-20 mpg range and still tow safely. and still have the 125" +wheel base and 5200 vehicle weight.
Because the toureg type of vehicle has considerable power at speed, (at least the mostly unavailable deisel V10, only 1500 are going to be allowed in this year, so unless you want to pay 58K, your going to get a V8 gas) the tendency is to think that it is an all perfect multiuse vehicle. But there are tradeoffs.......and the touregs profile, weight distribution, braking ability, resistance to lateral pressure, do not indicate better highway speed towing than a standard size pickup.
On the flat, fewer than 4,000 miles a year, wide roads, and little traffic passing you at 75-80 mph, keeping th mac weight below 4,000, you can probably get by with many smaller midsize vehicles...... (Which is probably 95% of most mac owners) just dont expect it to last as long towing as a full size towing rig tho.
Maybe a better title for this thread would have been ..something like..
"minimum safe tow vehicle for a 4500 llb mac and trailer for towing less than 4,000 miles a year and never up a 6 % grade more than 2 miles long.) and having the mechanicals last for 100,000 miles"