I know that there is always a tire debate happening so maybe this will lighten the mood :)I bought a new TT... small fella at 17 ft (21 ft with the tongue). For reference it's a clipper/viking 17BH which is a bit over 2800 dry and over 3600 GVWR. It came with some 13" tires and wheels.Well on a sort of related note I have a little utility trailer that I've always had fat little 8" tires on and I've recently started using it more and over longer distances than to my moms to mow her lawn and with larger loads. I had already decided to start looking into larger/better tires for it when the TT purchase idea happened.I am now considering buying three new tires/wheels for the TT and taking the three that came with it and popping them on the utility trailer. A simple move of the wheel wells on the little trailer will suffice and the wheels are the same 5x4.5 pattern.My real question is, since I'm going down this path would there be a safety or other decent reason to move up in tire size on the TT assuming the wheel well and springs are able to handle it... even if only to 14's or 15's? I know I'll have a slightly larger step up (roughly 3/4" per inch of tire maybe) and that's no big deal. Thanks for any pointers.-kkOH

If you do decide to change, if possible go to 15 inch. A friend had a really difficult time trying to find reasonably priced 14 inch tires recently. You have a lot more choices with 15 inch, but watch out for clearance issues especially above the tire contacting with the floor of the TT..

the bear II wrote:If you do decide to change, if possible go to 15 inch. A friend had a really difficult time trying to find reasonably priced 14 inch tires recently. You have a lot more choices with 15 inch, but watch out for clearance issues especially above the tire contacting with the floor of the TT..Just got off of the phone with a Forest River service rep who says that 15" tires would be to large for the well and that at most I might be able to bump up to 14's.

I'm not clear on something, what problem are you trying to solve? It's a myth that 13" tires are bad or prone to failure. Myself having owned a similar sized single axle trailer with 13" tires for 10 years, I think you would be better off simply getting new 13" tires with a higher load range, but I think they are hard to find. I towed our little trailer out west on a 6k mile trip and another that was 3k miles. I ran the original set of 13" ST tires for 6 years and put at least 15k miles on them. I replaced them with the same size and load range. I never once had a problem. Keep in mind to that increasing the tire size and load range will not increase your CC. You axle is the limitation.

Campfire Time wrote:I'm not clear on something, what problem are you trying to solve? It's a myth that 13" tires are bad or prone to failure. Myself having owned a similar sized single axle trailer with 13" tires for 10 years, I think you would be better off simply getting new 13" tires with a higher load range, but I think they are hard to find. I towed our little trailer out west on a 6k mile trip and another that was 3k miles. I ran the original set of 13" ST tires for 6 years and put at least 15k miles on them. I replaced them with the same size and load range. I never once had a problem. Keep in mind to that increasing the tire size and load range will not increase your CC. You axle is the limitation.I'm not trying to solve a problem at all Chuck. That's why I'm posting. I am just trying to find out if there is an advantage to up-sizing. I'm perfectly fine sticking with 13's if there's not a compelling reason to go larger - that's why I was asking the community. The current tires are Westlake ST185/80R13's with 8 Ply/Load D. I've read that the quality of the tire that manufacturers pop on new units isn't necessarily the greatest and looked at my needs on the utility trailer and thought it was an opportunity to upgrade both.

Those are the same size as my old trailer and current one. Another note is that I'm on my 3rd season with the current trailer and no trouble with the tires.This may help you think it through. One thing I've been taking note of is that the tire failures we're seeing reported on various forums seems to largely be the large rigs with 15" tires. I've seen a couple of 14", and almost no one with 13" failures. In particular it's the Chinese made TowMax brand that folks are worked up about.

Any benefit to upsizing my tires/wheels? | Good Sam Community

kkOH
Explorer
May 26, 2015
So then aside from the casual observations that people seem to make, the one benefit of going up to even a 14" would be less revs/minute = less heat on the bearings/tires = less chance of a meltdown?

And again, It's not like I'd be doing this only for the sake of doing it. I have a real need on my utility trailer to get three new tires. That trailer carries much less load anyhow and is mainly used to grab supplies from the hardware store, tow my mower or 4 wheeler, or cart the kids around in the back 40 when we're having a ho-down.
JIMNLIN
Explorer III
May 26, 2015
The 1710 lb rating is for a single wheel.

The 1620 lb is for a dual wheel application such as a rear dual set up on a one ton DRW truck.

Your correct. The 1710 times two equals 3420 lb total.
kkOH
Explorer
May 26, 2015
They are 185/80R13s (Westlake)

For what it's worth here's the wording that is on the tires:

MAX LOAD SINGLE 1710 LBS at 65 PSI
MAX LOAD DUAL 1620 LBS at 65 PSI

What I don't understand is if the single/dual is talking about axles but that seems like the way it would be. So if they're rated at 1710 per tire since it's single axle that would rate it to 3420, would it not?

(An example replacement that came up on etrailer from a google search shows a Kenda tire that is also rated for D which lists 1725 LBS at 65 PSI: http://www.etrailer.com/Tires-and-Wheels/Kenda/AM1ST79.html)
goducks10
Explorer
May 26, 2015
Your TT at max weight is 3626lbs. Minus 12% for tongue weight =3190lbs.
13" tires come in two sizes 175-185-80/13"
The 175 @1360lbs x2=2720lbs
The 185 @1480lbs x2=2960lbs

Neither one of those tires are adequate for that TT.

I would be talking to the dealer and see whats going on.
kkOH
Explorer
May 26, 2015
I appreciate all of the comments thus far. As stated earlier, my options are to stick with 13s, or bump up to 14s. The wheel well will not accommodate a 15" tire without modification of the springs/axle which I wont due since it will void my warranty.

We had our first short trip this past weekend and all was good as far as the tow goes. Next month we're taking a longer haul (3-4 hour drive 85-90% highway driving). It's trip like that I'm more worried about. If bumping from 13 to 14 doesn't gain me much in terms of safety (bearing heat, etc.) then I won't upsize. I'm working on a single axle and relatively light trailer.

If the debate about tire brands is less valid than many seem to think then I'm fine sticking with the stock tires. If there are actual numbers behind the "feelings" that people seem to have then I'd still consider swapping these out for something with a more solid track record and using the stock tires/wheels on my utility trailer.
JIMNLIN
Explorer III
May 23, 2015
Every trailer (all types) I've ever bought that came with 13" tires the first thing I did was dump them for a larger 14" tires on tandem axles and 15" on single axles.
Benefits I found were less rolling resistance.
Taller tires roll over obstacles easier...makes for a smoother ride.
Less wheel speed makes for a cooler running axle bearings.
More tires sizes available.
And for me it was less tire issues. Those small 13" suckers at 65 mph were turning some very high revs per miles = more heat.
Campfire_Time
Explorer
May 22, 2015
hawkeye-08 wrote:

The mfgs put the smaller tires on to save money. They put the cheapest ones on that meet the requirements.

It is likely that a larger tire will contribute positively to the 3 items you mention above and more,

1. Safety - larger may not fit and rub/cause damage. Handling may be affected in adverse conditions, if the larger tires fit okay, then likely they would be safer. They would likely have more capacity and since the circumference is bigger on larger tires, would turn slower at the hub and reduce bearing issues and run cooler since they would likely have higher load capacities.
2. Handling - taller profile, catch more wind and be more prone to sway (corners, wind etc)again, taller does not mean softer sidewalls, they may have stiffer sidewalls and handle better
3. Economy - Will sit higher, catch more wind, use more fuel. Also the tires themselves cost more later for replacement. I doubt that you would notice a difference in economy with an inch or two higher trailer. It often costs less to purchase more popular tires and wheels rather than the small sizes that are not that popular. A taller tire will pull over things easier and may even avoid damage from low clearance of the smaller tires.

Yes, there are limits to what you can gain to larger tires and wheels, but I would change in a heartbeat to 15" if available and they fit. You may need to adjust hitch for level trailer when towing...

Go for it

I'm guessing you've never towed with 13" tires. I have for many years, see above post.

Everyone of those points is marginal at best. It's really just the prevailing thinking, i.e. opinions. No numbers to back it up. Larger tires are just a "feel good" to give you a nice warm and fuzzy. When the tires actually do need to be replaced, that's the time to consider a bigger tire. But to replace perfectly good tires and wheels for the very small gains you might get just isn't worth the hassle.
gmw_photos
Explorer
May 22, 2015
If you have room for a tire that is 25.4" in overall diameter, then a Kumho 857, in 185R-14 would be a choice.
hawkeye-08
Explorer III
May 21, 2015
extremis wrote:
I can't see a larger tire improving any of these. your trailer was designed with 13" in mind, so its probably the safest size for all 3 points.

1. Safety - larger may not fit and rub/cause damage. Handling may be affected in adverse conditions
2. Handling - taller profile, catch more wind and be more prone to sway (corners, wind etc)
3. Economy - Will sit higher, catch more wind, use more fuel. Also the tires themselves cost more later for replacement.

The good about bigger tires - more ground clearance for boondock camping or rougher terrain and wheel bearings turn slower so less heat created and should last longer.

I don't imagine the MPG drop would be huge with taller tires, but from a technical standpoint its a possibility.

Thats my take on it. my trailer states I can put 15inch on it (its an optional wheel) but I stuck with the 14's. Mostly because I am cheap and didn't want to bother replacing the wheels.

The mfgs put the smaller tires on to save money. They put the cheapest ones on that meet the requirements.

It is likely that a larger tire will contribute positively to the 3 items you mention above and more,

1. Safety - larger may not fit and rub/cause damage. Handling may be affected in adverse conditions, if the larger tires fit okay, then likely they would be safer. They would likely have more capacity and since the circumference is bigger on larger tires, would turn slower at the hub and reduce bearing issues and run cooler since they would likely have higher load capacities.
2. Handling - taller profile, catch more wind and be more prone to sway (corners, wind etc)again, taller does not mean softer sidewalls, they may have stiffer sidewalls and handle better
3. Economy - Will sit higher, catch more wind, use more fuel. Also the tires themselves cost more later for replacement. I doubt that you would notice a difference in economy with an inch or two higher trailer. It often costs less to purchase more popular tires and wheels rather than the small sizes that are not that popular. A taller tire will pull over things easier and may even avoid damage from low clearance of the smaller tires.

Yes, there are limits to what you can gain to larger tires and wheels, but I would change in a heartbeat to 15" if available and they fit. You may need to adjust hitch for level trailer when towing...

Go for it
extremis
Explorer
May 21, 2015
I can't see a larger tire improving any of these. your trailer was designed with 13" in mind, so its probably the safest size for all 3 points.

1. Safety - larger may not fit and rub/cause damage. Handling may be affected in adverse conditions
2. Handling - taller profile, catch more wind and be more prone to sway (corners, wind etc)
3. Economy - Will sit higher, catch more wind, use more fuel. Also the tires themselves cost more later for replacement.

The good about bigger tires - more ground clearance for boondock camping or rougher terrain and wheel bearings turn slower so less heat created and should last longer.

I don't imagine the MPG drop would be huge with taller tires, but from a technical standpoint its a possibility.

Thats my take on it. my trailer states I can put 15inch on it (its an optional wheel) but I stuck with the 14's. Mostly because I am cheap and didn't want to bother replacing the wheels.

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