Reasons for 16" Wheels

[md11flyer]

Hi everyone. I recently acquired my first AS, a 1988 29' Excella and am in the process of making it fully functional, road worthy, and comfortable; Not necessarily a restoration but putting my kind of TLC into the unit. So, for the running gear I put on new trailer rated radial tires to get it home (seller thought the old ones were about 10 years old). Made it home safely and the trailer pulled well and did not notice any issues with the wheels and tires. My research on this forum for several issues has led me to the question of why should I upgrade my wheel size from the factory 15's to 16's. Would this improve my GVWR (now 6800#)? Is there any data that says I am reducing the rolling resistance on the AS and therefore will get better mpg on my TV (2012 F150 EB with 20" shoes)?
Is it going to improve the ride for the non-occupants of the trailer? Do 16" wheels look substantially better than the 15s? Why not put on some classy aluminum wheels and reduce the weight and mass over the stock steel wheels?

As a new guy to this forum, I have already learned a lot about these wonderful RVs and I look forward to learning more about what you think considering these wheel questions. Thanks in advance for all of your inputs!!

[pappy19]

A lot of your questions really depend on the final weight of your AS. On the other hand, ST tires have been a hit & miss for a lot of folks on this forum and many, including myself, have tossed the 15" ST tires for 16" LT's. Some just keep their 15" rims and change to LT's but you can't get an E rated tire for a 15" rim. Also, many of us have added the Centramatic auto balancer to the wheels to further insure an even wear pattern. I personally have had bad luck with ST tires and went to a 16" Michelin M/S-2 E rated tire. I also use a tire pressure sensor on trips, just in case.

[Bill M.]

Nothing will change the GVWR. It is written on the tag. Same GVWR as our 1988, 25' Excella. About 800 lbs of the wt will be carried on the TV. You probably have 3200 lb axles. I run the 15" Michelin XL tires. Max load for trailer use is 1985 lbs at max 50 psi. That gives a good safety margin for the tires. They work fine on the steel rims if that is what you have. Trailer pulls well and has good traction. Trailer seems to ride smoothly. No tire wear. I would not go to 16" wheels and heavy LT tires for that trailer. I would be worried about beating it up. I put about 40000 miles on the first set and changed them last year after 5 years because of aging. I have no idea of the effect of tires on millage. The radials are supposed to be low rolling resistance on cars so why not on trailers?

[Wingeezer]

I went to 16" wheels because I wanted to switch from ST to LT tires.

In my case I could not get an LT tire that matched my GVW rating - even if it had matched, it would have been very close to running at max capacity, so I would have felt happier with more of a margin of actual weight versus max. capacity just on principle.

If my trailer had been much lighter, (as the older AS trailers were), I believe I could have bought 15" LT tires that would have been ok for me.

But such was not the case. I was a bit surprised when one AS dealer tried to convince me to go to 15" LT tires even though they didn't match, let alone exceed my GVW rating. I chose not to go that route.

Just returned from our first 5300 mile trip on the new LT ties and 16" wheels. Very happy with them. I also use Centramatics and TPMS to try to do everything I can to minimize tire issues that could cause expensive trailer damage. No guarantee of that though, so fingers remain crossed!

Brian.

[Al and Missy]

I went to 16" after vacillating for a month or so. The reasons were more subjective than objective. LT tires are rated for trailer service, according to tire rack. P-metric LTX tires are rated for light truck service. I don't know whether, by extension, they are rated for trailer service. In today's litigious environment, I chose to be conservative.

While the 15" P/LTX tires have ample margin under normal conditions, on my trailer if the other tire on that side should fail, there would then be around 2800# on that 1985#-rated tire and it should probably be replaced along with the one that failed, assuming that the failure of the first tire was noticed before the second one failed. With the 16" tires, there would be 2800# on a tire rated for 2685#. I'm more comfortable with that setup.

I don't know about the claims of greater potential for damage to the trailer. The ST tires run at 65#. It doesn't seem that increasing to 80# would make that much difference. If it did, I could reduce pressure to 65# and still have a tire rated for 2335# according to Michelin's tables. That said, the P tires run at a maximum of 50 psi and should, therefore, transmit less shock from bumps to the axle and then to the trailer.

Bottom line, there are plenty of people on here running either of ST, P, and LT tires with no trouble but there appear to be many more having problems with the ST than either of the other two options. You have to be the judge of what you are more comfortable with.

Al

[woodfox45]

If you have 15" steel wheels they are rated for 55psi if you go to aluminum 16" wheels they are rated for 82 psi . The cost of a 15"versus 16" alum. wheel isn't much different ,And you can't buy a 15" LT tire ( at least i couldn't ) I have a 29' also and went the 16" LT tire and so far so good .

[woodfox45]

I forgot to add the aluminum wheel isn't much lighter than steel since they are much thicker material so weight won't be a factor in your decision . however they won't rust either

[Jammer]

Originally Posted by md11flyer

Hi everyone. I recently acquired my first AS, a 1988 29' Excella and am in the process of making it fully functional, road worthy, and comfortable; Not necessarily a restoration but putting my kind of TLC into the unit.

Cool. Have fun!

So, for the running gear I put on new trailer rated radial tires to get it home (seller thought the old ones were about 10 years old). Made it home safely and the trailer pulled well and did not notice any issues with the wheels and tires. My research on this forum for several issues has led me to the question of why should I upgrade my wheel size from the factory 15's to 16's.

The only reason to change wheel sizes would be because you don't like any of the 15" tires and want to run 16" ones.

Which tires make the most sense for you is a topic that pretty much everyone on the forum will have an opinion about.

Would this improve my GVWR (now 6800#)?

No.

Is there any data that says I am reducing the rolling resistance on the AS and therefore will get better mpg on my TV (2012 F150 EB with 20" shoes)?

No.

Is it going to improve the ride for the non-occupants of the trailer?

No.

Do 16" wheels look substantially better than the 15s? Why not put on some classy aluminum wheels and reduce the weight and mass over the stock steel wheels?

There are a wide range of choices in steel and aluminum wheels, with a wide range of weight and pressure ratings, in both sizes.

As a new guy to this forum, I have already learned a lot about these wonderful RVs and I look forward to learning more about what you think considering these wheel questions. Thanks in advance for all of your inputs!!

The 16" wheel upgrade is an expensive one. It may make sense for people who travel long distances at high speeds in hot weather with a heavy trailer. If cost is no object and your other renovations are fully funded, it's something to consider.

[Larry C]

Originally Posted by pappy19

A lot of your questions really depend on the final weight of your AS. On the other hand, ST tires have been a hit & miss for a lot of folks on this forum and many, including myself, have tossed the 15" ST tires for 16" LT's. Some just keep their 15" rims and change to LT's but you can't get an E rated tire for a 15" rim. Also, many of us have added the Centramatic auto balancer to the wheels to further insure an even wear pattern. I personally have had bad luck with ST tires and went to a 16" Michelin M/S-2 E rated tire. I also use a tire pressure sensor on trips, just in case.

Several companies make E rated 15" tires. I've got a set of Carlysles (sp)
on our 30' Excella. Just don't buy Chinese tires.
For whatever it's worth.
Larry

[perryg114]

If you put E rated tires on the trailer and run them at 80 psi it is like having solid wheels on the thing. Most road vibrations and small bumps are taken up by the tires. The suspension takes care of the big hits and it can't respond to the high frequency stuff. The 235/75 XL15 are good tires. I don't think you will overload them. It won't hurt to run 16" wheels and it gives you more room for things like disk brakes. I would not run the E rated tires at over 60psi.

Perry