Max tire/wheel size for 2003 2720

[tentcamper]

Does anyone know if you can go to a 15 inch wheel/tire on the 2003 -2720 without the lift mod? If so what would be the max size tire that would fit?

If the 15 inch does not have the clearance. What is the max 14 inch tire that will fit?

 

[TM Pilot]

Does anyone know if you can go to a 15 inch wheel/tire on the 2003 -2720 without the lift mod? If so what would be the max size tire that would fit?

If the 15 inch does not have the clearance. What is the max 14 inch tire that will fit?

14" tire to 15" tire upgrade without lift kit on a 2003 - 2720?: Probably not. However, it may be best to answer your generic questions by first looking at a specific 2003 - 2720 and seeing what you have to work with. Sounds like you may have found one!

I know that the TM Dealer, The Car Show Inc., in Colorado Springs, CO charges about $215 to install the 2.5" lift kit. Many TM Owners have installed the lift kit themselves.

Use the "search" feature to find posts on these topics. There are many that already address these questions - at least to the degree to give you some generic answers. And by reading them you may discover additional issues you were not aware of that may impact your tire choices (i.e. if I upgrade to 15" tires, will my TM with a/c fit into my garage?).

 

[Bill]

It would be nice if there were a simple yes/no answer. But to continue TMPilot's response, tires from different manufactuers (and even different lines of tires from the same manuafacturer) have different dimensions. In other words, a 14-inch tire from one manufactuer won't have the same dimensions as a 14-inch tire from another. You need to know what the dimensions are for the tires you are considering. Once you know the dimensions, there are two rules of thumb to use.

1. The width of the new tires should not exceed the width of the old ones. The loaded width of a tire is part of its specification, and can be found online for the tire you are considering. This is a rule of thumb, and you might have 1/4 inch to play with, but not much more than that.

2. According to Dexter Axle, who makes the wheel and axle assembly for TMs, there should be 3 inches of clearance above the tire - between the tread and the wheel well liner - when the trailer is loaded. If you put on a larger tire, its loaded radius will likely increase, which decreases the clearance you have above the tire. But the difference between a 14-inch Marathon and a 15-inch Marathon, for example, is surprisingly small. Again, loaded radius is a spec that you can look up for the tires you are considering. This rule of thumb appears to have a lot of flexibility, since the max deflection of the suspension is only an inch or so (again, according to Dexter). So, many of us (including me) run with only 2 inches of clearance, and are quite happy.

So - it is time to get out your ruler, do some measuring, and then get on line. Hope this helps.

Bill

 

[tentcamper]

Correct we have TM lined up. Looks very nice via pictures and per the conversation with the owner. It sound like it will work very well for us. For the age of the camper it seems like it's above average condition. Price seems to be fare. As always, i'm sure if I waited there would be a better deal. But were committed to the seller based on a verbal agreement and the owner has it on hold until we get there. Only issue, I do need to change all 3 tires, only because the're to old for my liking. Been there with old tires popping on a trip and taking out the sewage drains.

So in thinking about tires. Figured I would do some research, as to what options I have that could increase the tire load rating. I was hoping someone already knew the answers. It sound like I need to do some measuring? Thanks for the dexter recommend 3" clearance info.

 

[TM Pilot]

tentcamper,

Are you planning on replacing the tires to get the TM home or after the fact?

First thing is to find out what rims you have on the TM. The TM owner's manual doesn't have any info on rims. You need to look on the rim itself for it's size and its limitations. There will be a stamp somewhere on the rim. If you plan on using the rims currently on the trailer you will have to limit your tire selection to the rim's size and limitations and the measurements of your wheelwell.


For example, on my 07 TM 2619 my factory rims are 14"x6" with a weight limitation of 1870lbs. I [safely; conservatively] assume that the rim also has a limitation of 50psi. I currently have Goodyear Marathons ST215/75R14 14" tires (load range C: 1870lbs @50psi).
With that in mind, here are my 3 options for my specific TM:

1. Use the factory 14" rims (1870lbs @50psi) with 14" tires in load range C (1870lbs @50psi).
2. Upgrade to non-factory 14" rims (2000+ @65psi) with 14" tires in load range D (2000+ @65psi).
3. Upgrade to 15" rims & tires and install lift kit (required on my TM).

If I choose:

1. I will use Maxxis M8008 ST225/75R14 (load range C). If I wanted a bias tire I would choose Kenda Loadstar K550 ST215/75D14 (load range C).
2. I will use Kenda Karrier KR03 ST205/75R14 (8ply; load range D). (Note: There are only a few products offered for a 14" load range D tire. Choices are very limited!)
3. Haven't made a decision about this option yet. However, if I needed to replace the factory rims, I would probably upgrade from option 1 to 3 and skip 2 unless the TM couldn't fit in the barn. Haven't figured out the specific measurements yet. But by ballparking it last week, if I go with the 2.5" lift kit and 15" tires, I will have probably have, at best, less than 1/2" to spare between the A/C unit and the 7' opening of my barn.

Hope this helps.

 

[Shrimpburrito]

With that in mind, here are my 3 options for my specific TM:

1. Use the factory 14" rims (1870lbs @50psi) with 14" tires in load range C (1870lbs @50psi).
2. Upgrade to non-factory 14" rims (2000+ @65psi) with 14" tires in load range D (2000+ @65psi).
3. Upgrade to 15" rims & tires and install lift kit (required on my TM).

TMPilot - FYI, there's no reason for your option #2. Some other folks have thought this as well, so I just want to point this out. The rims are not the problem, the tires are. The object here is to get a tire with a higher weight rating to reduce tire failures, and if you can do that in a 14" tire (as I have done before), then it will fit on your existing 14" rim. If such a beast existed, you could put a 14" 5,000-lb rated tire on those rims. You couldn't carry 5,000 lbs because the rims would be your limiting factor, but it would give a huge safety margin with your tires.

The only circumstance in which you should be replacing your rims is to put a 15" tire on there, such as your option #3. Having already tried a 14" tire with a high weight capacity (Kumho 857's) and experienced blowouts in both tires, that's what I would recommend. After those bad experiences, like others here, I upgraded to 15" rims/tires and haven't had a problem since.

Dave

 

[tentcamper]

That's my thoughts regarding the rims. I'm not increasing the weight being carried just not as close to maxing out the tires.

I will pull it back with the old tires. It will be slow going. I would stop and get tires, but it seems every time I go to get the tires I want. It seems the tire shop has to order them and I do want to measure to see if I can go with a 15. I will not be pulling it back with a WDH, so I won't have all extra weight being distributed to the trailer tires and from the dips in the road being applied to the trailer axle from the WDH.

Just my thoughts. I would only use radials. Had my fill of bias ply tires and feel radials are much safer. I have had very good success with the Marathon tires and we do a lot of miles on our trips and we're hard on them traveling on a lot of poor quality roads. The thing I like with radials, is you can drive for hours and stop and when you feel the tires there the same temperature as the TV tires. The bias ply tires would almost burn. Also, the feel of pulling bias ply there is a secondary response feel when entering and exiting curves, where with radials it like the trailer is on rails.

 

[tentcamper]

Dave were you able to go to 15" without the lift kit?

 

[TM Pilot]

TMPilot - FYI, there's no reason for your option #2. Some other folks have thought this as well, so I just want to point this out. The rims are not the problem, the tires are. The object here is to get a tire with a higher weight rating to reduce tire failures, and if you can do that in a 14" tire (as I have done before), then it will fit on your existing 14" rim. If such a beast existed, you could put a 14" 5,000-lb rated tire on those rims. You couldn't carry 5,000 lbs because the rims would be your limiting factor, but it would give a huge safety margin with your tires.

The only circumstance in which you should be replacing your rims is to put a 15" tire on there, such as your option #3. Having already tried a 14" tire with a high weight capacity (Kumho 857's) and experienced blowouts in both tires, that's what I would recommend. After those bad experiences, like others here, I upgraded to 15" rims/tires and haven't had a problem since.

Dave

Dave,

In addition to weight (1870lbs), I consider pressure (50psi) to be a limiting factor on my TM's factory 14" rims. I haven't seen any documentation from Trailmanor or markings on my factory rims that state otherwise. I am also not aware of any 14" rim made by any manufacturer that is limited to 1870lbs yet is also rated to 65psi. Therefore, I'm not comfortable being a test pilot and fitting a 14" load rating D tire filled to 65psi on a rim that is, most likely, limited to 50psi. In my opinion, that's not safe.

No rim manufacturer is going to authorize one to fill their rims over the maximum pressure for the rim. That a tire mounted on that rim can handle a higher pressure is irrelevant. Safety limits itself to the most restrictive component.

Here is one example from a rim manufacturer (see pg. 10): http://www.accuridecorp.com/files/2...d-Service-Manual-ACC7-0002-Rev-4-06-22-12.pdf

Here is one example from a tire manufacturer: http://www.tirerack.com/images/tires/goodyear/Marathon_Special_Trailer_Applications.pdf

Here is an example from Dexter Axle: http://www.dexteraxle.com/i/u/6149609/f/600-8K_Service_Manual/Wheels_and_Tires.pdf


Rim, tire, and axle manufactures all agree that one should not fill a rim (a.k.a. wheel) beyond its maximum pressure.


Lots of TM owners with 14" rims/tires have never blown their tires. Some with 15" rims/tires have blown theirs.
Did you have your 14" Kuhmo's mounted on your TM factory 14" rims or mounted on aftermarket 14" rims when they both blew out 3 years later? What was the maximum psi limitation for your rims? Just curious.

Bruce

 

[tentcamper]

I could be wrong, but from the pictures I have seen it looks like the rims are dexter "Dexstar rims'?

What I see online, they are rated for 65 psi and 2,040 load. But there should be a sticker or stamping on the rim for the max load and psi.

Here is a link to the rim that I referenced. http://www.etrailer.com/Tires-and-Wheels/Dexstar/AM20352.html

 

[tentcamper]

With the 14 inch ST radial tires it seems to be limited to either 205 or 215 with a max rating on the 215 of 1,870. Are there any other radial tires with a higher capacity that anyone knows of?


I will not go to bias ply tires. Had my run with them.

 

[Bill]

Although it won't answer all questions, there is some relevant info in this post.

http://www.trailmanorowners.com/forum/showthread.php?t=6245

Bill

 

[TM Pilot]

I could be wrong, but from the pictures I have seen it looks like the rims are dexter "Dexstar rims'?

What I see online, they are rated for 65 psi and 2,040 load. But there should be a sticker or stamping on the rim for the max load and psi.

Here is a link to the rim that I referenced. http://www.etrailer.com/Tires-and-Wheels/Dexstar/AM20352.html

My 14" TM factory rims are stamped 1870lbs max on the outside of the rim. I have yet to pull the tire off the rim and look for any stampings on the inside of the rim.

I wrote TM and asked for the manufacturer of the 14" rim and its psi limitation. So far no answer. Until I know otherwise, I'll limit the 14" rim to 50psi. It is made in China!

 

[Shrimpburrito]

Dave,

In addition to weight (1870lbs), I consider pressure (50psi) to be a limiting factor on my TM's factory 14" rims. I haven't seen any documentation from Trailmanor or markings on my factory rims that state otherwise. I am also not aware of any 14" rim made by any manufacturer that is limited to 1870lbs yet is also rated to 65psi. Therefore, I'm not comfortable being a test pilot and fitting a 14" load rating D tire filled to 65psi on a rim that is, most likely, limited to 50psi. In my opinion, that's not safe.

No rim manufacturer is going to authorize one to fill their rims over the maximum pressure for the rim. That a tire mounted on that rim can handle a higher pressure is irrelevant. Safety limits itself to the most restrictive component.

Here is one example from a rim manufacturer (see pg. 10): http://www.accuridecorp.com/files/2...d-Service-Manual-ACC7-0002-Rev-4-06-22-12.pdf

Here is one example from a tire manufacturer: http://www.tirerack.com/images/tires/goodyear/Marathon_Special_Trailer_Applications.pdf

Rim and tire manufactures both agree that one should not fill a rim (a.k.a. wheel) beyond its maximum pressure.


Lots of TM owners with 14" rims/tires have never blown their tires. Some with 15" rims/tires have blown theirs.
Did you have your 14" Kuhmo's mounted on your TM factory 14" rims or mounted on aftermarket 14" rims when they both blew out 3 years later? What was the maximum psi limitation for your rims? Just curious.

Bruce

Of course, lots of TM owners have never blown their 14" tires. It's just a matter of odds -- what level of risk are you comfortable with? I had 3 blowouts on 14" wheels (one Marathon, two Kumhos) within a 3-year period, and may others here with 14" wheels were having the same problem, so I decided that if I didn't want more blowouts, I was going to have to make a change. The risk was too much for me. Having a blowout is a near surefire way to ruin your weekend, and worse, can do major damage to the TM.

Yes, I had my Kumhos mounted on my TM factory 14" rims - I don't know what the pressure limit was, but since they were OEM, it was probably 65 psi like yours. The Kumhos had a max pressure of 65 psi, so that never exceeded the pressure limit of the rims. After upgrading to the 15" tires, I did run them briefly at 70-80 psi, but that shook the crap out of the trailer, so now I always run them at 65 psi. And in using the lower pressure, I still have a significantly higher weight carrying capacity than I did with the 14" wheels, which I feel reduces my risk of a blowout. And this change in turn has left me with zero blowouts after 4 years and many thousands of miles.

IMHO, the bottom line is if you can fit 15" tires on there, that's your best bet by far.

I had to put the lift kit on mine, but that was inexpensive ($40), and easy to install (a little more involved than changing a tire, less involved than changing bearings or brakes).

Dave

 

[TM Pilot]

Yes, I had my Kumhos mounted on my TM factory 14" rims - I don't know what the pressure limit was, but since they were OEM, it was probably 65 psi like yours. The Kumhos had a max pressure of 65 psi, so that never exceeded the pressure limit of the rims.
Dave

Since there is a correlation between a rim's weight and pressure limits, 1870lbs is correlated to 50psi, not 65psi. If someone can find a 14" rim that is rated by the manufacturer to 1870lbs @65psi - please post the link. To date, when I have searched for a 14" rim rated to 1870lbs it always stated a maximum pressure of 50psi. But the internet is a big place...

 

[Shrimpburrito]

All I can say is that many on this forum, including myself, have run 14" tires at pressures higher than 50 psi (as I said before, my Kumhos were at 65 psi) on OEM rims. Have never heard of any sort of rim failure on either this forum on the Casita forum, where the Marathon/Kumho debate has also been argued extensively. I acknowledge that does not mean it's within spec, but on the other hand, I also would argue that it certainly could be within spec, if there even is one. And most importantly, I would argue it's better than using 14" tires on those same rims.

Perhaps wmtire will chime in with his opinion, as this is his professional area of expertise.

Bottom line -- 15" wheels and tires make this a mute debate.

Dave

 

[TM Pilot]

Filling a rim to 65psi that is only rated to 50psi may not produce a dramatic, catestrophic blowout hole through the metal rim. However, over time it may deform the rim just enough to be an additional link in a tire failure chain. The deformation may not be noticable to the naked eye or felt while driving. Measuring a rim without the tire mounted using the proper tools may reveal hidden defects. Same principle applies after blowing a tire - Get your rims inspected for defects and make sure the tire "professional" uses measuring tools and not just his eyeballs to be certain the rim in still in spec!

Dave, do you still have your old 14" rims laying around? If so, might be interesting to put a carpenter's square on them and see what it says.

 

[Bill]

Dave et al -

I think it is terribly dangerous to inflate a tire without knowing what the rim will take. If the OEM tires take 50 psi, then I would not assume that the rim can take any more than that.

Most of us have occasionally seen news stories about some shade-tree mechanic who overinflates a tire to the point where it explodes. Quite often it kills him, since his face is near the tire when it explodes. I'm quite sure that if a rim explodes, it is just as likely to be fatal with all those metal hunks flying around.

As noted in an earlier (much earlier) post, the rim's pressure limits, along with load-bearing capacity and other info, is likely stamped into the interior of the rim. In other words, once the tire is mounted on the rim, you can't see the stamped info any more. You must check for the info while there is no tire on the rim.

Just my opinion. But count me out on this operation. It scares me way too much.

Bill

 

[Shrimpburrito]

Filling a rim to 65psi that is only rated to 50psi may not produce a dramatic, catestrophic blowout hole through the metal rim. However, over time it may deform the rim just enough to be an additional link in a tire failure chain. The deformation may not be noticable to the naked eye or felt while driving. Measuring a rim without the tire mounted using the proper tools may reveal hidden defects. Same principle applies after blowing a tire - Get your rims inspected for defects and make sure the tire "professional" uses measuring tools and not just his eyeballs to be certain the rim in still in spec!

Dave, do you still have your old 14" rims laying around? If so, might be interesting to put a carpenter's square on them and see what it says.

I agree with you to an extent, and frankly, I had not even considered that rims had a pressure limit until you mentioned it in this thread. But I personally am not concerned about the debate because I have 15" wheels.

I don't have my old 14" rims. My last 14" blowouts were in Colorado in the middle of a transcontinental trip, and since I didn't have room to take 3 rims with me, the tire shop kept/scrapped them. Of course, this was also on a Sunday afternoon, when few tire distributors are open. Did I mention how blowouts can really ruin your day?

Dave

 

[tentcamper]

How come it always seems that the tire shop does not have the tire you need and they have to get it from the warehouse.

But getting back more on track. It sound like i need to do some measuring.