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lewster · 04-07-2007, 08:32 PM

I'm about to take the plunge and replace my OEM alloy rims and 15" ST Goodyear trailer tires with 16" alloy rims and Michelin 225/75-16 LRE truck tires....the same ones I have been using on my Sprinter. Just because the CAN be inflated to 80psi doesn't mean that you HAVE to inflate them to that. I intend to put 65psi in them, just like I run the 15's in my CCD now.

I also run the front of my Sprinter at that pressure and have not had a problem in 70K miles. I don't want a tire failure from excess heat at ANY speed and just don't feel comfortable running the Goodyears at their MAXIMUM pressure all the time!!!!

Beginner · 04-07-2007, 09:20 PM

Soldiermedic
Go to this website.

http://airstream.net/members/documen...%20Catalog.pdf

This is a 1968 Catalogue for Airstreams.
On page 28 (by pdf count) is a list of standard specifications for the trailers.
The 9th irem down lists the size, wheel and load range for the different configurations (6 ply=Load Range C:
8 ply = Load Range D).

Email Airstream and ask them what tire they recommend for your trailer. If they come back with an answer of "Goodyear Marathon ST225/75R15" then look up that tire on the goodyear website and write down the outside diameter and width of the Marathon.
Email Michelin and ask them what the outside diameter of the Michelin XCA 700x15 8 ply truck tire was.
With the max width of the Marathon and the outside diameter of the Michelin XCA and staying with an 8 ply tire (Load Range D) you can crawl through the tire specification charts and pick out out what you want.
For a jump start, the Eagle Alloy 0589-7766 (16 inch aluminum wheel, pull up my pictures to see what they look like) and the B. F. Goodrich Commercial T/A should work just fine.
Beginner

dmroot · 04-07-2007, 09:31 PM

This is such a rich thread of tire info that I am posting pics and a question that I had placed over on my 1971 Safari thread...

Yesterday we replaced the four old 8-ply tires on our dual axle 1971 Safari (which we just bought and towed home on Monday). The front two tires had a very odd diagional-cupping wear pattern on them.

Here are the pics...Has anyone seen this on an airstream before? Any ideas on the cause?

scottanlily · 04-07-2007, 11:48 PM

soldiermedic ,you can use 700-15 LT tires bias ply if you desire .The goodyear
workhorse rib is one good choice ,in 8 ply load range D. you also can use the ST radial trailer tire in 15" ,but I strongly recommend to research your ST
tire of choice before purchasing (read problems) and beginner definately has given very good recommendations and info . your single axle needs an 8 ply rated D tire ,a C range is too light for your trailer ,however sugarfoot
has been running some cool wide white tires on her 60 trdwnd single axle
without any problems ,but shes careful on the weight to not excede the capacity of the tires .

Scott

Beginner · 04-08-2007, 05:36 AM

What size are these tires?
What type of tires are these, bias or radial?
What who made them?
Judging from the pictures those tires with the drastically uneven tread were in the early stages of disentegration.
Determine whether or not you have steel belt pieces sticking out because the next test will shread your hand if they are.
To tell if the belts have slipped on a belted tire(either radial or belted) lay your hand across the tread area of the tire, finger tips on one sholder, heel or wrist over the other sholder(palm against the tread).
Then rub your hand (flatly, palm against the tread) all the way around the tire tread area.
The tread area should be quite flat and or symetrical.
Small flat depressed areas 3-5 inches in diameterare usually caused by a combination or bad shocks and out of balance tire/wheel/brake drum(running gear).
Other shaped areas that seem to be raised and are longer than wide are usually belt seprations.
Beginner

ticki2 · 04-08-2007, 06:29 AM

Dmroot

Check your brakes , it looks like those tires were skidded. Is it just one place around the tire or several?

dmroot · 04-08-2007, 02:21 PM

The old tires are now at Les Schwab heading for the tire graveyard...but we replaced them with the same size: 700-15/8. The old ones were Toyo and the new ones are Nan Kang Highway N101 Blackwall (or at least that's what they put on our reciept).

Getting the running gear up to snuff is our next step...We are planning brakes and bearings next. We are also doing a lot of reading on axles (just in case that was the problem) and we need to understand this 'balancing of the axles' thing to be sure we get that done somehow...

Beginner · 04-08-2007, 06:58 PM

Don't understand what you mean by "Balancing the Axles".
It would be nice if we could find a machine shop that would dynamically balance brake drums to 1000 RPMs though.
Beginner

Inland RV Center, In · 04-09-2007, 09:53 AM

Quote:

Originally Posted by Beginner

Don't understand what you mean by "Balancing the Axles".
It would be nice if we could find a machine shop that would dynamically balance brake drums to 1000 RPMs though.
Beginner

Beginner.

Ouch, 1000 rpm for a 15" tire, by my quick calculations, would mean a speed of 89.25 MPH.

Way too fast, to be safe.

DMROOT.

Your photos show tires that were "grossly out of balance."

You donj't balance "axles," but you do balance the complete running gear as an assembly. That's the tire, wheel, hub and drum.

Andy

Beginner · 04-09-2007, 12:23 PM

Andy
Dealing with engines I have found it better to dynamically balance at a slightly faster speed than everyday use.
I didn't look up the revolutions of the tires at 62 MPH but figured them to be near 700 rpm give or take.
Anyway
1000 rpm would well cover any contingency.
Will I tow 89 MPH, no.
Didn't mean to give you a start.
Beginner

Inland RV Center, In · 04-09-2007, 12:38 PM

Quote:

Originally Posted by Beginner

Andy
Dealing with engines I have found it better to dynamically balance at a slightly faster speed than everyday use.
I didn't look up the revolutions of the tires at 62 MPH but figured them to be near 700 rpm give or take.
Anyway
1000 rpm would well cover any contingency.
Will I tow 89 MPH, no.
Didn't mean to give you a start.
Beginner

It's not the "start" that hurts people, it's the "sudden stop" because of an accident.

Towing at a high speed is risky.

But, when we are younger, we sometimes do silly things.

Like the time, in 1973, I towed a loaded 31 foot Airstream with a hot Buick, with a calibrated speedo, total weight 14,500 pounds, at 115 MPH.

Anything past 90 MPH, makes the Airstream handle like a super dream.

Captured it on film, but can't find the film.

Andy

soldiermedic · 04-09-2007, 01:31 PM

Andy,

I need new wheels and tires for my 68 safari. I was wanting to switch to 14" rims, but many have said it isnt a good idea. The trailer is getting a new "Lighter" floorplan than before.

What would you recommend for aluminum rims and tire, and where can I get them?

Inland RV Center, In · 04-09-2007, 01:57 PM

Quote:

Originally Posted by soldiermedic

Andy,

I need new wheels and tires for my 68 safari. I was wanting to switch to 14" rims, but many have said it isnt a good idea. The trailer is getting a new "Lighter" floorplan than before.

What would you recommend for aluminum rims and tire, and where can I get them?

DO NOT switch to 14" wheels. You will be sorry the day you did.

A lighter floor plan will not appreciably change the running gear requirements.

Use ST 225/75R15 load range "D" tires. We only recommend Goodyear Marathons.

We do not sell or get involved with aluminum wheels. Way too many types, designs, ratings, and personal opinions.

Purchase wheels that have at least a 2600 pound rating.

Additionally, have you checked out the axle, to make sure that you have plenty of wheel well clearance, especially vertically?

If not, then go to. Dura Torque Axle

Andy

soldiermedic · 04-09-2007, 02:13 PM

Ok, goodyear marathon tires...anyone else out there know where I can get some nice 15" wheels that have the weight rating Andy mentioned?

Silver Threads · 04-09-2007, 02:19 PM

We bought some tires the other day from Tucker Tire. These are 10ply 7-15LT tires. After reading what Andy had to say we figured we had better not use them. I emailed the guy, below is his answer:

never heard of such a thing on the 80 lb pressure. they will work fine with 45 to 50 lb and not hurt your rims. I have eight ply will ship for you if you want to exchange or will give u a refund if you send them back. I put the ten ply on all kinds of trailers every day with no problems thanks

John

Inland RV Center, In · 04-09-2007, 02:28 PM

Quote:

Originally Posted by Silver Threads

We bought some tires the other day from Tucker Tire. These are 10ply 7-15LT tires. After reading what Andy had to say we figured we had better not use them. I emailed the guy, below is his answer:

never heard of such a thing on the 80 lb pressure. they will work fine with 45 to 50 lb and not hurt your rims. I have eight ply will ship for you if you want to exchange or will give u a refund if you send them back. I put the ten ply on all kinds of trailers every day with no problems thanks

John

Obviously, your tire dealer has little knowledge of an Airstream.

Airstream and Argosy trailers "LOVE" a soft ride.

Load range "E" tires have side walls that are to stiff to permit that soft ride, regardless of pressure.

Is this the same person that always sells the "E" tires on e-bay?

Andy

soldiermedic · 04-09-2007, 02:35 PM

What is the difference in LT and ST tires? I used to work at a Walmart doing tires and always thought the LT was Light Truck.

What PSI should the tires be at for mounting?

Silver Threads · 04-09-2007, 02:41 PM

Our owners manual says 7 x15 6-ply 45psi, and 7x15 8-ply 60psi

John

Silver Threads · 04-09-2007, 03:14 PM

Load range "E" tires have side walls that are to stiff to permit that soft ride, regardless of pressure.

Andy,
The tires we have on our airstream now are 8ply, the tire says sidewall:4ply, tread 4ply. These are the ones that have been on it since we got it.

The ones we bought are 10 ply which you said the sidewalls are too stiff for an airstream, but these tires say sidewall 4ply, tread 6ply.

What would be the difference when both the sets of tires say 4ply in the sidewall??

Inland RV Center, In · 04-09-2007, 05:30 PM

Quote:

Originally Posted by Silver Threads

Load range "E" tires have side walls that are to stiff to permit that soft ride, regardless of pressure.

Andy,
The tires we have on our airstream now are 8ply, the tire says sidewall:4ply, tread 4ply. These are the ones that have been on it since we got it.

The ones we bought are 10 ply which you said the sidewalls are too stiff for an airstream, but these tires say sidewall 4ply, tread 6ply.

What would be the difference when both the sets of tires say 4ply in the sidewall??

Use the "E" tires and your Airstream will tell you the difference.

Depending on how many miles you tow the Airstream per year, it probably won't take long for your trailer to tell you to get it to a shop for vibration type repairs.

Many others in the past, have learned that lesson the hard way.

Andy