14" 215/75 to 15" 225/75 wheel & tire upgrade

[Ray Eklund]

I own a 2006 23 foot Safari. They were available with ONLY 14 inch wheels, 215/75/14 and Load Range C tires.

These are a five lug wheel in 14", unlike the six lug wheel in 15" on all of the USA domestic Airstreams in current production. I have found the Load Range C tires can be center tread rock punctured when off the asphalt road. Not from overloading or looking for trouble while towing into the back country. The Airstream engineers might have computed the Load Range C tires are fine for the weight of the 23 foot trailer ON asphalt, but I have found the tires are my weak link in gravel/dirt experiences.

When my tow vehicle tires, load range C, are due to be replaced, I go directly to load range D with NO failure problems with tires while towing off road. My trailer's Marathon load range C's just did not hold up for me. I have Tow Master tires at the present, load range C's, and they have been without problems... so far.

My question to you, the more experienced in trailer "upgading".

The Airstream 14 inch stock wheel is 7" wide and a 5 x 4.5" (5 lug, 4.5 inches apart with their measuring method). The 15 inch, 5 lug is available at 4.5 and 8" wide. I can then use on my Airstream's 5 lug wheels (drums), a 15 inch wheel that a 225/75/15 load range D tire can be used. It all seems to be a good fit for my need for a load range D tire that is ONLY available in 15" and NOT 14".

Where am I going wrong in my reasoning? It sounds too easy to be a solution. The dual axle wheel area has plenty of room in all directions.

[bobkelly]

Ray----There is nothing wrong with this upgrade and a lot right with it. You've listed a bunch of right reasons already. Be sure the replacement wheel has the same offset, zero, as the originals and the right load carrying capacity. Automotive wheels typically have a lower load rating than the same sized trailer wheel.

I'm in the same boat and plan to make a similar change. Which/whose wheel do you plan to buy?

[USA Roamer]

Ray, I Replaced my tires (Goodyears) with Maxxas M8008, load range D. I have pulled my 2005 30ft Classic ltd about 1200 miles sence they were put on, and have worked very well.
I have gained about 2000lbs extra safety margin over the marathons which were barely over the 10000lbs GVWR of the trailer.
Check them out before you spend all that money on new wheels,

[2airishuman]

hi ray...

given your time spent off road or in rougher terrain...

any highway tuned trailer tire might underperform...

here are a couple of options i've seen used on trailers that spend time off the beaten path...

14s or 15s...

http://www.nankangtyres.com.au/prodDetail.php?pid=21

http://www.nankangtyres.com.au/prodDetail.php?pid=23

this company also makes a generic marathon like tire branded as 'milestar'...

some are made in taiwan and other in china...

cheers
2air'

Originally Posted by USA Roamer

...I have gained about 2000lbs extra safety margin over the marathons...

roamer...

i hope the maxxis work well 4 ya...

while u may have gained some load capacity with those tires...

the stock wheels are only rated to 2200 lbs each x4 = 8800 lbs for your unit.

http://www.airforums.com/forums/433671-post3.html

[USA Roamer]

2air', where do you get the info on the wheels? I have not found it. What I am going is The tires that came on the trailer were load range E and cold preasure at 65lbs on sidewall.The goodyear chart rates this tire, ST225x14R75, at load capcity of 2540 lbs . With x4=10,160 lbs total capcity. The trailer GVW=10,000 lbs. That is a VERY LOW margin for error, to close for me! I just checked the maxxis chart and the load range D tire that I have on now is rated 2830 lbs with cold air preasure of 80 psi. I am running 70 lbs and when I stop the tires are just slightly warm to the touch.
I have been fooled before, but I can't believe Airstream, and Alcoa, would put rims on that are rated under 2500 lbs each. That would be an open invitation to a law suit if one failed.
No, this did not change the GVW of the trailer, it only gives me a little more tire safety on, and off, the beaten path.

[2airishuman]

Originally Posted by USA Roamer

... where do you get the info on the wheels? I have not found it...

roamer...

you can read the full thread that is part of the link provided.

the specs for the rim are stamped on the back side of each wheel...

i suspect that the tongue weight is not counted against the tire/wheel load bearing limits...

and that is how/why the specs/limits and actual a/s weights are 'legal'

i've not read or heard about failures in these alcoa rims, but they are very very light.

my point is that capacity is a combination of several factors and greatly increasing one doesn't negate the other limiting issues...

the rims are also rated to 95 psi, but running the tires at higher pressures may have some effect on ride quality too..

cheers
2air'

[Andrew T]

Hi Ray

An LT tire will give you much better puncture resistance than any trailer tire. We regularly upgrade trailers like yours to 15 or 16" rims. In your case you a great tire to use would be a Michelin LTX 235/75R x 15" LT Load range "C". These tires are rated for 50 PSI but with your trailer 40 PSI would be all I would run in them. You can purchase several rims that will work with your bolt pattern. I would suggest a 15*7" rims. American Racing is a good source they have chrome steel or aluminum rims that will work well.

Andy

[overlander63]

If you go with 15" tires, find wheels that are 7", not 8", wide. The wheel may be too wide to fit in the wheelwells.
I am not familiar with the brake drums on your coach, do you know if they are a standard size? If so, you could get 6 lug drums, and Airstream standard wheels.
You ccan also get D rated ST tires in a 205/75R15 size.

[mrchinup1]

Originally Posted by Ray Eklund

I own a 2006 23 foot Safari. They were available with ONLY 14 inch wheels, 215/75/14 and Load Range C tires.

These are a five lug wheel in 14", unlike the six lug wheel in 15" on all of the USA domestic Airstreams in current production. I have found the Load Range C tires can be center tread rock punctured when off the asphalt road. Not from overloading or looking for trouble while towing into the back country. The Airstream engineers might have computed the Load Range C tires are fine for the weight of the 23 foot trailer ON asphalt, but I have found the tires are my weak link in gravel/dirt experiences.

When my tow vehicle tires, load range C, are due to be replaced, I go directly to load range D with NO failure problems with tires while towing off road. My trailer's Marathon load range C's just did not hold up for me. I have Tow Master tires at the present, load range C's, and they have been without problems... so far.

My question to you, the more experienced in trailer "upgading".

The Airstream 14 inch stock wheel is 7" wide and a 5 x 4.5" (5 lug, 4.5 inches apart with their measuring method). The 15 inch, 5 lug is available at 4.5 and 8" wide. I can then use on my Airstream's 5 lug wheels (drums), a 15 inch wheel that a 225/75/15 load range D tire can be used. It all seems to be a good fit for my need for a load range D tire that is ONLY available in 15" and NOT 14".

Where am I going wrong in my reasoning? It sounds too easy to be a solution. The dual axle wheel area has plenty of room in all directions.

I am in the same position with my 23 fter, i wanted to upgrade my 14 inch wheels to 16 before i went on my CC trip. I can't believe AS cheaps their way out of putting 15's on this model, with a 48k list price. The 5 bolt pattern is the problem here. IMO Aristreams are over rated as being a premiem RV, for the money they get for these units.

[Andrew T]

Here is a picture of a 25' Safari that originally came with 14" wheels. These are 16*7" rims with 235/60 x 16" tires. These are not as good for off road use but on the highway they give great braking, handling and a smoother ride because they only need 35 PSI to carry a 25' Safari. This combination also works great on 34's but not on heavier tandam axle units.

Andy

[mrchinup1]

Complete hub and drum assembly with bearing, 72 dollars each for 6 bolt pattern.

[Ray Eklund]

Originally Posted by mrchinup1

Complete hub and drum assembly with bearing, 72 dollars each for 6 bolt pattern.

If I could not find a 15 inch wheel to fit a five bolt lug pattern, I would have to replace them for your suggestion. But, I can get 15 inch wheels that will work and it is just getting feed back on a 7" width or 8" width wheel. The ST225/75/15 Marthon Load Range D tires fit 8" wheel widths.

Maybe a LT Michelin tire might work better for my off road traveling better than a trailer ST tire...

It looks like my opportunity to learn from someone else who has gone from 14" to 15" wheels is getting less likely from responses received. There is a chance that the number of people converting wheel diameters is small, so I might have to experiment with wheel strengths and tire strengths on my own. I appreciate all of the suggestions and have worked them into my eventual decision. I also plan on keeping the current 14 inch wheels and tires in the event this does not work out for me...

[AlbertF]

Originally Posted by Andrew T

Here is a picture of a 25' Safari that originally came with 14" wheels. These are 16*7" rims with 235/60 x 16" tires. These are not as good for off road use but on the highway they give great braking, handling and a smoother ride because they only need 35 PSI to carry a 25' Safari. This combination also works great on 34's but not on heavier tandam axle units.

Andy

Andy,

Is that the full body paint Safari you had with the Michelin MXV4s? A very interesting tire choice. Would you comment on the use of passenger tires on a trailer?

[Andrew T]

Hi Albert

I have never been a big fan of “Travel Trailer Tires” as it seemed that was just code for too poor to use on a car. We find they loose their balance easily, get twisted belts and flat spot when you lock the brakes up. On most trailers these items are not an issue as they don’t balance the tires anyway and most trailers don’t have enough brakes to lock the wheels.

We sell a lot of 34’s as the tri axle has several advantages and we have one connected for test drives all the time. One tri axle disadvantage is the back axle unloads during moderate braking so the rear tires squeal fairly easily. Our best answer for that was to install 7.00 x 15” LT radials, they still squeal but they did not flat spot and of coarse durability was much better. Our thought was that a stickier performance tire might not lock up so easily and a 16” would look cool.

We have been using the 16” rim 235/60 x 16” tire combination since 1994 on 34’s mainly. We found there were added benefits as well the shorter stopping distance especially in the wet. They ride considerably smoother since we get precise handling at only 35 PSI and we have had great durability from them without the twisted belts etc. For replacement the performance tires do not cost a lot more than trailer tires but give far more quality but you do have to change the rims.

The first 25’ Safari’s came with 14” rims and they just look a little homely by today’s standards so if we have to change tires we often upgrade the rims to 16” with the 60 series tires. They look and ride much better. You cannot do this change on larger tandems or single axles as the load per tire is too high.

Lately we have been installing some Michelin 235/75R x 15” Passenger tires on 34’s with Hensley’s. This tire has quite a bit of sidewall roll so I would not put it on a trailer without a Hensley but it fits the 15” rim and gives a very soft ride. The idea here is to be easier on the Airstream shell and have a better quality tire.

Andy

[Andrew T]

Here is a picture of the whole Safari with the Full Body Paint. Sorry I don't have a better shot this one was one I had from the drag strip.

Andy

[Road Ruler]

Originally Posted by Andrew T

Lately we have been installing some Michelin 235/75R x 15” Passenger tires on 34’s with Hensley’s. This tire has quite a bit of sidewall roll so I would not put it on a trailer without a Hensley but it fits the 15” rim and gives a very soft ride. The idea here is to be easier on the Airstream shell and have a better quality tire.

Andy

Good day Andy... From the PO our 23' came with 235x75Rx15 Michelin performance, P rated tires (Sears branded with raised while letters).

The Sears tire manager looked up the numbers for us and reported that they were over 12 years old. He suggested replacing them with 235x75Rx15"XL" tires. They were still P rated and would provide a quality ride but the XL ( extra load) designation would provide a tough casing and 8,500lbs of load capacity. I thought I would try them because our loaded trailer is only 4,500lbs so we have lots of head room and the 35lbs pressure gives us a nice footprint and forgiving ride. They have been working fine for 5 years now and the Airstream handles just great even with strong crosswinds in this area.

Soon I will be looking for new tires and wondering if you would suggest I get the same if available or would you suggest something else. Note I too am not a fan of problematic ST tires.

[Andrew T]

I think in your case the P rated Michelins are fine so I would continue with them. The 23' is a stable trailer and your Infinity is a very stable tow vehicle so you should never have a control issue. You could drop to a 225/75R x 15" for a slightly less rolling resistance and slightly less overall height.

Andy

[slowmover]

On my non-Airstream trailer I changed the tandem axle tires to LT 7.00-15 YOKOHAMA RY-215 and have been pleased compared to the Carlisle tires present at purchase. Ck load rating for all applications.

[vswingfield]

Hi Andy,

Those are good-looking wheels. What kind are they and where did you get them. Six of those would look good on my Excella. Very swoopy paint job.

[Road Ruler]

Originally Posted by Andrew T

I think in your case the P rated Michelins are fine so I would continue with them.
Andy

Thnxs for the good advice Andy. I will probably go with the Michelin X1's as they worked so well on our Nissan Van for many years. The 225's will be the ideal size as well.