towing tandem with an airstream

[wvabeer]

I have 79 31' and was going to replace some rusty frame at the back and was wondering if I could put a 2" reciever on the rear and how much weight it could pull thanks Kenny

[Silverhobby]

Andy will agree and give you the reasons: Repairing rust and frame; GREAT----Towing or adding a hitch to the rear; FORGET THAT IDEA

[Inland RV Center, In]

wvabeer.

DON'T DO IT......

The bumper won't take it, the rear of the frame won't take it either.

Most importantly, you will change the tongue weight of your trailer back and forth as you tow. Then, your rig becomes out of control, no exceptions.

You would only do that once.

Andy

[overlander63]

Doubles with a semi is great, although not without issues, but the reason you can tow tandem that way is you have an additional set of bogies for the rear trailer to ride on, thus eliminating changes in tongue weight. This does nothing for the aditional buffeting forces on the frame of your trailer. Even a small trailer, riding on a set of bogey wheels for the tongue, would create so much stress on your coache's frame that you would be forever replacing rivets, sheared bolts, and blown out windows.

[wvabeer]

thanks ya'll I kinda figured the frame wasn't that heavy and never even thought about tongue weight thanks alot any pointers on replaceing the rear 3 ft of frame (it has the rear queen bed)

[CanoeStream]

My state allows you to tow a boat behind a 5th wheel. Somebody from the Twin Cities rolled all 3 units just west of here last month -- probably had a minor lapse of attention and overcorrected.

But the basic info above is but a simple restating of many other threads (Thank you for your lengthy advice in the past, Andy!!!) -- you don't even want to load bicycles onto the back bumper -- the lever arm effect magnifies the stress on the frame the further aft the load is placed.

[wahoonc]

An Airstream is a dynamic structure...kind of like flying in a airplane, the wings are in constant movement, if you over stress any single part of the structure it can lead to failure. Airstreams are the same way, they are constantly flexing as they move down the road and anything you do to change the orginal stresses is more than likely going to lead to problems. Stiffening up something that was designed to move can lead to more problems somewhere else...

Aaron

[Silvertwinkie]

Originally Posted by wvabeer

I have 79 31' and was going to replace some rusty frame at the back and was wondering if I could put a 2" reciever on the rear and how much weight it could pull thanks Kenny

Not in this lifetime....as the others have said, bad idea....just don't do it or bad things can happen to the Airstream.

[Inland RV Center, In]

wvabeer

Why do you need to replace the rear 3 feet of frame?

Depending on the reason, it could suggest other problems as well.

I will be happy to help you, if I can.

Andy

[blnfuse]

Hey wvabeer weve got the same idea !
Since I have been doing a frame up renovation I have done just what you have suggested. I did replace many members and outriggers that were lost to rust and also added the frame work for a gray water tank. (it's a 63).
So I said to myself " self you know enough about this metalugical stuff just git er done". so I did. I just have one word of advice.
KEEP IT SMALL! less than 50# toungeweight.
I love it when I find others that think outside the alluminum

[Inland RV Center, In]

blnfuse.

The dead weight of the material you added, is only part of the story.

"Moment arm" is the other part.

50 pounds added to the rear end of a typical 26 foot trailer is about 500 pounds, sitting still. Hitting bumps when traveling causes that weight to multiply rapidly.

To find the "moment arm", you measure the distance from the rear axle tube to the bumper. In your case it's about 10 feet. Therefore you must multiply the weight times the distance.

In the case of wvabeer, he has a 31 foot trailer. The moment arm in his case is almost 13 feet (typically), which means the same 50 pound weight is actually 650 pounds.

This is why rear end separation occurs, which is also caused by unbalanced running gear.

The bottom line answer is "DON'T DO IT" unless you move the axle or axles rearward, at least 12 to 18 inches.

If you move the axles, then you "might" be ok.

Also, how a 63 shell and floor is attached to the frame, is very different from a 1979 trailer.

Remember, the construction is semi-monocoque, which means the shell is "load bearing", just like an aircraft.

Therefore in spite of popular belief, the frame DOES NOT hold up the shell.

In fact, the shell holds up the frame.

Therefore when you add weight, as you have suggested, you progressively make it more difficult for the shell to do it's job.

You will never find an aircraft with much weight in the tail. The same thing applies to any Airstream or Argosy trailer every built.

Andy

[wvabeer]

Originally Posted by Inland RV Center, In

wvabeer

Why do you need to replace the rear 3 feet of frame?

Depending on the reason, it could suggest other problems as well.

I will be happy to help you, if I can.

Andy

This trailer had sat for 12 years beside the allagainy river on one side and a rock wall on the other side with the rear window leaking very slghtly at the back the water was laying in the belly pan for years and rusting the bottom of the main frame 5" C channel so I bought new 3" and 5" C channel so I could replace all of the pieces back there and I think if I go back 3 ft. Ithink it should get it all, by the way the part of the frame that you can see attached to the bummper is almost gone on both sides

[Inland RV Center, In]

wvabeer

I would strongly suggest before you do anything to the frame, remove all of the underbelly and inspect the complete frame.

If it turns out to be a waste of time so be it. However, I think you quite well may find more of the frame rusted in other aeras as well as the rear.

Better to make sure, than guess.

While you have the frame opened up, you could also clean it up and spray it with undercoating.

Andy