Tires....Tires.....Tires - Page 3

Inland RV Center, In · 05-11-2005, 06:24 PM

Coloradobus.

Since you will have a 6000 pound axle, your trailer is going to considerably bounce around.

That being the case, anything you put on the bumper will also bounce around, but even more so since it is some distance from the axle.

Measure the distance from the center of the axle, to the center of your proposed bike rack, in feet, including the fractions.

Multiply that distance by the weight of the two bikes and the added steel. That is what is known as a "moment arm".

What weight do you now have?

Remember that is a dead weight. As you move the trailer, that weight multiplies very fast. A multiplier of 4 to 5 is very common, when hitting bumps.

But we already know that your trailer will be verty bumpy to start with, because of the over rated axle.

Those being proven factors, I would suggest you put the bikes in the trailer, in the tow vehicle, or leave them home.

To install a bike rack, in your specific case on the rear bumper, will shortly lead to more problems than you wish to hear about.

Rapid rear end separation, again in your case, is at the top of the list especially if you tow it with your 4X4 and have heavy rated torsion bars.

On the other hand, it's your trailer and money.

Andy

Bob Thompson · 05-11-2005, 06:38 PM

Goodyear Says LT tires are for Light Trucks, Busses, TRAILERS, and Multipurpose Passenger Vehicles. Check here:

http://www.goodyear.com/truck/pdf/da...dInflation.pdf

Coloradobus · 05-11-2005, 06:40 PM

I'm not saying I'm a fan of Carlisle Tires. It was just brought to my attention they had a load range "E". I plan on using Marathon Goodyears, ST225X75X15 LR "D"

What is the rated weight for a 6-bolt pattern, 12 inch brake equipped Henschen to be put on a '67 Globetrotter??
What would be the loaded inflation tire pressure be on a Load Rainge "D" tire compared to a LR "E" for a Globetrotter?? (IF I WAS TO USE ONE)

Inland RV Center, In · 05-11-2005, 06:52 PM

Coloradobus.

The axle load rating for older year 22 foot Airstream trailers is as follows.

Please note the upgrading as time went by, because of failures.

1961 22' 3600 pounds
1962 22' 3600 pounds
1963 22' 4000 pounds
1964 22' 4000 pounds
1965 22' 5000 pounds
66 to 69 22' 5000 pounds

Therefore upgrading the load carrying capacity 10 to perhaps 15 percent maximum, on the earlier models is OK, and recommended as per Henschen.

Andy

Bob Thompson · 05-11-2005, 07:02 PM

In my search, I had a hard time finding aluminum wheels with a six lug pattern with a weight rating in excess of 2600 pounds, but there are a few. However, it was fairly common to find steel trailer wheels with six lugs and a weight rating of 3300 pounds. If you are going to use Load Range E tires you will have to use wheels rated for 3000 pounds or more. Most of this is due to the 80 psi required in most Load Range E tires.

Rog0525 · 05-11-2005, 07:05 PM

Quote:

Originally Posted by Bob Thompson

Goodyear Says LT tires are for Light Trucks, Busses, TRAILERS, and Multipurpose Passenger Vehicles. Check here:

http://www.goodyear.com/truck/pdf/da...dInflation.pdf

Goodyear does not manufacture Airstream travel trailers. Airstream does not manufacture tires.
Airstream recommends ST tires for the coaches they build. I put more trust in Airstream than I do in Goodyear.
Not trying to be argumentive, just explaining my opinion.
Tires are temporary, Airstream trailers are permanent.

Coloradobus · 05-11-2005, 07:14 PM

Thanks Andy, It appears that we may have gone just a bit heavier for our year of A/S, but given the weight the tires will carry per PSI Chart, we will have a better ride than we have now with an old maxed out axle.

uwe · 05-11-2005, 07:58 PM

Quote:

Originally Posted by Coloradobus

Sorry, I guess I missed that.. We have ordered this axle(6K lbs) and its now in. I need to go and pay for it and bring it home for installation. If it tears the GT up, oh well. It can't be any worse than our current original. The excitement of a new axle install surely has been deflated.

Glad we have an SOB motorhome. Its not so delicate.

Sorry to have helped deflate your enthusiasm. I wish I could have given you advice sooner. I report from experience with oversprung Airstream axles. My intent is not to be negative, but to share my concern for your joy in Airstreaming.

Coloradobus · 05-11-2005, 08:06 PM

Thanks Uwe, This axle by any stretch of the imiagination has to better than our current dead axle. The trailer leaves the ground on highway bumps with a thud and it jerks the truck. We plan on adding a grey tank in the future as well as a/c and microwave. We have added all new oak wood to the interior. (overhead roof locker doors are the only original wood) and underlament to the floor, larger LP tanks, electric jack, etc.

Coloradobus · 05-11-2005, 08:30 PM

Uwe,

Just thought of one item in The Axle info I received. This axle we ordered is for trailers that weigh up to 6,000 lbs, and not less than 3,800 lbs. The lesser axle is for trailers weighing up to 3,800 lbs. This is why we ordered the stouter one. Isn't it better to have an axle that is not maxed out all the time?

SilverToy · 05-11-2005, 11:08 PM

Andy -

Thanks for the tutorial on weights, hitches, heavy duty vehicles, etc...

Never seen anything, or heard it either for that matter, in such a direct and forthright manner as re: towing and needs as far as vehicle vis-a-vis WD hitch and tow weight. Thanks for that. This is in no small measure what makes these posts and this board so valuable. Just can't get this info elsewhere!

Now to my question.... Have an '01 2500 HD Burb with a Equalizer 1200lbs WD hitch for a '92 34' Classic AS. Am I to heavy on the weight bars??? Pulls great! No tugs, no sway, nothing! Not on 2 lane roads, or highway - perfect. In fact, had a center tire blow out and never saw or felt a thing - noticed it at a rest stop and was SHOCKED to see only side walls. No damage other than a slightly polished shock mount.

Just wondering as I read the comments about the "over-ige" on sway bars, weight etc vs. trailer weight and such.

Thanks for your time and thoughts!

Ciao

Axel

uwe · 05-12-2005, 01:28 AM

Quote:

Originally Posted by Coloradobus

Uwe,

Just thought of one item in The Axle info I received. This axle we ordered is for trailers that weigh up to 6,000 lbs, and not less than 3,800 lbs. The lesser axle is for trailers weighing up to 3,800 lbs. This is why we ordered the stouter one. Isn't it better to have an axle that is not maxed out all the time?

I don't know which axle you bought or what their ratings are, but my feeling is that for Airstream trailers the actual fully loaded weight of the trailer should be close to the axle rating, say within 500lbs on the lighter trailers, or perhaps 800-1000lbs on dual axle, heavier units.
Torsion axles can be tuned to within a few hundred pounds of their rating by the length of the rubber rods inside the axles. I feel that a rating of somewhere between 3800 lbs and 6000lbs is a bit of a stretch to fine tune a smaller Airstream.
The idea is to have a decent amount of pre-load on the axle, so that it will ride semi-soft, with the given maximum weight. If the axle is too stiff, then it might handle much like a worn axle, just at a higher ride height.
Again, not meaning to burst your joy, just passing on my limited experience with these pesky axles.

Bob Thompson · 05-12-2005, 06:50 AM

So Andy, this moment arm you mentioned in association with the bike rack, would you say it is very much like a moment of inertia, or is it more like a radius of gyration. Seems to me it may likely be more of a pitching moment. Perhaps you could explain exactly how this works.

Bob Thompson · 05-25-2005, 09:32 AM

Update: The wheels came in at about the same time the tires arrived at Discount Tire. Yesterday, I took the wheels over to get the tires mounted. When I arrived, there was a fellow with a Jayco 5th Wheel ahead of me. He had just limped in on his spare tires, having suffered two Goodyear Marathon tire blow-outs at the same time on the same side of the trailer. He was putting on Carlisle LR-E 15" tires.

As for my BFG Commercial T/A's they are very stout looking tires. The tread depth is about 30% deeper than I anticipated and the overall quality seems to be exceptional. Checked the date codes and the tires were made in late January of 2005.

The wheels are lugcentric so I made sure they used the lug adapter to balance them and I made sure they put in the heavy duty valve stems. A little more balance weight was required than I am used to with Michelins, but not too bad.

With the tires and wheels in hand I went home, pulled the trailer from its storage cocoon and installed them. The new American Racing Outlaw II rims and 225/75/16 tires are about 1.25" larger in diameter than the previous tires, but there were no fit or closeness issues. Looks like my forethought in measuring and verifying before hand was worthwhile.

I'll report again after having towed them several hundred miles, which will happen in 10 days when we go to the Austin Airstream get together at McKinney Falls State Park. Round trip should be about 500 miles so it will be a good test of the tires.

Inspection of my old tires determined I was about to have another blowout. The radial belts were squirming in the casing causing big flat spots about the size of your hand where tread depth was about 1/8" less than adjacent areas. Scarry! I could have been coming at you sideways!