Reply
 
Thread Tools Search this Thread Display Modes
 
Old 04-06-2008, 10:23 AM   #15
1 Rivet Member
 
2002 19' Bambi
Auburn , Maine
Join Date: Mar 2006
Posts: 13
Quote:
Originally Posted by Road Ruler
I think that was proven to be a Myth, wasn't it?
Was it? I hadn't heard that before. It always made sense to me when I thought about the Plymouth Fury wagon my father drove compared to most of the cars around today. But I could certainly have that wrong.
__________________

__________________
FilmGuy is offline   Reply With Quote
Old 04-06-2008, 11:38 AM   #16
4 Rivet Member
 
1975 27' Overlander
High River , Alberta
Join Date: Aug 2006
Posts: 393
If the Plymouth Fury wagon was built in the 1960s or 1970s, it was a unibody.

Unibodies are far stiffer than frames. It's like comparing the strength of an engineered roof truss to a floor joist. The roof truss will do a far better job of resisting deflection due to load.
__________________

__________________
AlbertF is offline   Reply With Quote
Old 04-06-2008, 03:18 PM   #17
Rivet Master
 
SteveH's Avatar
 
2005 39' Land Yacht 390 XL 396
Common Sense , Texas
Join Date: Sep 2007
Posts: 5,311
I don't think the problem with unibody cars pulling trailers is stiffness, it's attaching the hitch to them, as even the strongest sections of them are made from very light guage sheet metal. Frames on the other hand, are made from much heavier sheet metal. Just my thoughts on the matter.
__________________
SteveH is offline   Reply With Quote
Old 04-06-2008, 05:57 PM   #18
4 Rivet Member
 
1975 27' Overlander
High River , Alberta
Join Date: Aug 2006
Posts: 393
Quote:
Originally Posted by SteveH
I don't think the problem with unibody cars pulling trailers is stiffness, it's attaching the hitch to them, as even the strongest sections of them are made from very light guage sheet metal. Frames on the other hand, are made from much heavier sheet metal. Just my thoughts on the matter.
A good point. Hitch installation often requires some creativity. It's easiest when manufacturers design the attachment points in, such as Chrysler does with the 300/Magnum. (Have a look under these cars, and you will find pre-threaded holes.) This can be augmented with attachments to other points, such stamped or cast independent rear suspension components.

Another consideration - high strength steels are now used to build cars, and the thin sections may be a lot stronger than they look.
__________________
AlbertF is offline   Reply With Quote
Old 04-06-2008, 06:02 PM   #19
Rivet Master
 
Fyrzowt's Avatar
 
2000 25' Safari
West of Fort Worth , Texas
Join Date: Aug 2006
Posts: 6,697
Images: 8
On a side note...

Quote:
Unibodies are far stiffer than frames. It's like comparing the strength of an engineered roof truss to a floor joist. The roof truss will do a far better job of resisting deflection due to load.
Until fire hits them, then they fail quickly.
__________________
AIR #15800

"Wimpy" 1/2 ton 2002 GMC Sierra 4X4 Z-71 Gasser
2000 Safari SS 25'
Fyrzowt is offline   Reply With Quote
Old 04-06-2008, 06:23 PM   #20
Rivet Master
 
Road Ruler's Avatar
 
Currently Looking...
St. Catharines , South Western Ontario
Join Date: Aug 2002
Posts: 2,364
Images: 39
Steve has made a good point about the sheet metal VS frame rails.

I have seen a number of custom, pro built receivers on uni-bodies that get around the sheet metal issue and are in fact much stronger and flex resisitant than a conventional bolt on type of receiver.

With some luck form member Andrew T will chime in to explain as he has successfully figured out the formula.
__________________
Airstreams..... The best towing trailers on the planet!
Road Ruler is offline   Reply With Quote
Old 04-06-2008, 06:44 PM   #21
Rivet Master
 
Road Ruler's Avatar
 
Currently Looking...
St. Catharines , South Western Ontario
Join Date: Aug 2002
Posts: 2,364
Images: 39
Quote:
Originally Posted by Fyrzowt
Until fire hits them, then they fail quickly.
??????
__________________
Airstreams..... The best towing trailers on the planet!
Road Ruler is offline   Reply With Quote
Old 04-06-2008, 07:05 PM   #22
Rivet Master
 
Fyrzowt's Avatar
 
2000 25' Safari
West of Fort Worth , Texas
Join Date: Aug 2006
Posts: 6,697
Images: 8
Road Ruler,
The metal plates that hold trusses together heat up, charring the wood around the plates. These cause catastrauphic roof failures. Many of my peers have been injured, some killed over this design.

Now back to the thread, sorry for the detour.
Dave
__________________
AIR #15800

"Wimpy" 1/2 ton 2002 GMC Sierra 4X4 Z-71 Gasser
2000 Safari SS 25'
Fyrzowt is offline   Reply With Quote
Old 04-06-2008, 09:51 PM   #23
Vintage Kin
 
slowmover's Avatar
 
Fort Worth , Texas
Join Date: Nov 2006
Posts: 7,603
Images: 1
Quote:
Originally Posted by FilmGuy
It's also worth a mention that those family cars were heavier and were built on frames. Today's cars are unibody construction designed to be light-weight for gas mileage. So they don't have the mass or the stiffness to resist a trailer's sway forces.
No, sir, the cars from Chrysler Corporation were all uni-body from 1957 and were probably the first choice among full-timers. A unibody vehicle is MORE resistant to TV-induced towing problems. In fact, some Chrysler cars were banned from demolition derby since they were indestructible by comparison to body-on-frame cars.

As to weight my old big block 1971 Chrysler was at 4,760# with full fuel, passenger and some trunk-junk. My half ton truck with a small block (same otherwise) weighed an additional 5-600#. (As were the comparable Oldsmobiles of the early 1970's). And got less fuel mileage than the big motor. We won't talk about acceleration, handling or braking.

As to boilovers, only on cars not maintained properly (I believe people are a little better about it these days). No one in our family experienced one, but the replacement of water pumps at around 70,000 miles was common.

Electrical problems then, and now, are the reason 80% of vehicles are in the shop.

Cars have a lower center of gravity, can handle abrupt manuevers safely that would put a truck in the ditch and have better power to weight ratios. Let's not overlook their qualities. There is no good reason NOT to consider a 120" wheelbase V8 car of today to tow.
__________________
1990 35' Silver Streak Sterling; 9k GVWR.
2004 DODGE Cummins 305/555; 6-manual; 9k GVWR.
Hensley Arrow. 9-cpm solo, 15-cpm towing
Sold: Silver Streak Model 3411
slowmover is offline   Reply With Quote
Old 04-07-2008, 07:19 AM   #24
1 Rivet Member
 
2002 19' Bambi
Auburn , Maine
Join Date: Mar 2006
Posts: 13
OK, so I guess I had that wrong. But if all this is true - and I accept that is is - why are we all towing with pickups and suvs? I think a Dodge Magnum would make a great TV for an AS!
__________________
FilmGuy is offline   Reply With Quote
Old 04-07-2008, 07:49 AM   #25
Well Preserved

 
1993 21' Sovereign
Colfax , North Carolina
Join Date: Jun 2003
Posts: 20,193
Quote:
Originally Posted by FilmGuy
OK, so I guess I had that wrong. But if all this is true - and I accept that is is - why are we all towing with pickups and suvs? I think a Dodge Magnum would make a great TV for an AS!
I have been told by a reliable source that Chrysler is discontinuing the Magnum.
__________________
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.
Terry
overlander63 is offline   Reply With Quote
Old 04-07-2008, 12:22 PM   #26
Rivet Master
 
cameront120's Avatar
 
1972 25' Tradewind
North Vancouver , British Columbia
Join Date: Feb 2006
Posts: 3,422
Images: 23
Just for kicks, of the sedans/station wagons presently being manufactured, which of them would make good tow vehicles?
__________________
Cameron & the Labradors, Kai & Samm
North Vancouver, BC
Live! Life's a banquet and most poor suckers are starving to death! - Mame Dennis
cameront120 is offline   Reply With Quote
Old 04-07-2008, 02:26 PM   #27
Rivet Master
 
SteveH's Avatar
 
2005 39' Land Yacht 390 XL 396
Common Sense , Texas
Join Date: Sep 2007
Posts: 5,311
Quote:
Originally Posted by cameront120
Just for kicks, of the sedans/station wagons presently being manufactured, which of them would make good tow vehicles?
Just to start off, I would say all that are V8 engine equipped, and rear wheel drive. So then, how many are there? The only two that come to mind quickly are the Ford Crown Victoria and the Mercury Grand Marquis, which are basically the same car. Personally, I wouldn't consider any of the front wheel drive cars built today, but this is just my opinion.
__________________
SteveH is offline   Reply With Quote
Old 04-07-2008, 04:29 PM   #28
Vintage Kin
 
slowmover's Avatar
 
Fort Worth , Texas
Join Date: Nov 2006
Posts: 7,603
Images: 1
The Crown Vic has a shorter wheelbase than the 300/Charger. It is also IFS and live axle rear. A good bit of overhang. But, it has the advantage of being essentially unchanged since 1979. The incremental changes have made a superior fleet car. That is it's great advantage: long service life, reliable and well-known by service departments across North America.

I believe that it is underpowered for trailer pulling, but I'd use one if I had to up to about 5,000#.

The 300/Charger is based on on the E-Class Mercedes sedan of a generation or three back. Fully independent suspension, 120" wheelbase (the minimum, IMO) and plenty of power from the Hemi (or, the 3.5L V6 for lighter trailers). The AWD system is based on the very good Mercedes EMatic (name?).

I, too, think the Magnum would be a VG choice. It is likely in its last year of production.

The only "drawback" to these cars is their small fuel capacity. They don't have the 24 or 28 gallon capacity of yore. On the other hand, modern engine management offsets that with better fuel economy.

My grandfathers '68 Monaco (with 3.23 gears, B727 trans and 440 Magnum) had a 23 gallon fuel capacity. He recorded 10 mpg for all driving, pulling a 28' Streamline, therefore a reasonable range with reserve was about 200 miles.

A 300/Charger, with an 18-gal tank needs only to achieve 12 mpg to equal that range.

My Dad's '76 Cadillac got 7-8 mpg pulling his Silver Steak (bigger motor than the above but an inferior design for power and the usual 1970's emissions changes on top of that), so his 27.5 gal tank equalled about the same.

In other words, a car has about 200 miles of range versus a big diesel pickup having well over 400 with reserve (if you bought a Cummins, anyway).

Depending on the trailer, it's use and the owner, a car may well be the best double-duty vehicle, (with the inconvenience of more fuel stops). But, for trip planning purposes, being out of the vehicle every three hours or so is actually quite good for safety purposes (feeling rested).

As to unit-body, the only non-stressed items (non-load bearing) would be the hood, trunk lid and doors. Everything else is. Sorta like an Airstream. Or a Boeing airliner.
__________________

__________________
1990 35' Silver Streak Sterling; 9k GVWR.
2004 DODGE Cummins 305/555; 6-manual; 9k GVWR.
Hensley Arrow. 9-cpm solo, 15-cpm towing
Sold: Silver Streak Model 3411
slowmover is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Trailer length & state park campsites CanoeStream Airstream Trailer Forums 26 05-28-2007 11:37 AM
Trailer length standards jcanavera Airstream Trailer Forums 4 08-10-2006 06:16 PM
Airstream trailer length? Mariner On The Road... 2 10-20-2003 10:14 PM
pipe running length of trailer outside belly skin?? Bailey56 Exterior Storage Compartments & Access Doors 2 08-07-2003 09:30 AM
Trailer weight Dbraw 1969 - 1973 Safari 3 06-26-2002 01:01 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:57 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.