Dumb trailer tire question

[Elkins45]

Technically I think this question is more about the axle, hub and weight distribution but it’s caused by a tire, so…

My 16.5’ aluminum boat (around 1300 pounds including the trailer) came with 13” wheels, but since all 13” trailer tires seem to be garbage I bought a set of 14” wheels and mounted Goodyear trailer tires on them. My spare, however is still a 13” and I wonder how much of a problem it would be driving with it mounted for several hundred miles to get home. The boat would obviously be tilted toward the smaller wheel and my understanding of vectors makes me think that would make the tire, hub and axle on that side carry over 50% of the weight since the boat would be tilting “downhill” into the smaller tire.

Should I spend more money for a third 14” wheel and tire or am I overthinking this? Or should I just carry all three of the old 13” tires with me as a backup LOL?

 

[spasm3]

I'd want the spare to match.

 

[NiwradND]

I would not worry about the spare, unless you plan on getting flats. Most people that keep good tires on the trailer never use their spares. I would gamble on it, but you can pick up a spare tire and rim fairly cheap.

 

[Rand]

Should I spend more money for a third 14” wheel and tire or am I overthinking this? Or should I just carry all three of the old 13” tires with me as a backup LOL?

Theoretically you would only need to carry a pair.

I wouldnt worry about it for short distance, but for hundreds of miles.. no where to stop and get a trailer tire?

 

[Nick1994]

I would have zero concern

 

[Chris142]

Nothing to worry about

 

[dnewton3]

Because this is just a trailed axle and not a drive axle (with a diff), then the size disparity between a 14" and 13" tire would be minimal and you'd never know it when towing at a reasonable speed. Also, the axle would only be nominally 1/2" lower on the one side; it's only the radius of the wheel that affects the distance to ground, not the diameter.

I would not spend the extra money on upsizing the spare.

 

[Doc8404]

My F150 came with 18” spare while wearing 20s all around.

 

[George Bynum]

My F150 came with 18” spare while wearing 20s all around.

I believe that you will find them to have very close to the same revolutions/mile. 2WD are about 30.5" diameter, 4WD are about 31.5" OD.

 

[y_p_w]

I would not worry about the spare, unless you plan on getting flats. Most people that keep good tires on the trailer never use their spares. I would gamble on it, but you can pick up a spare tire and rim fairly cheap.

I've seen a tire blowout in front of me, where I was avoiding all sorts of junk. And at that point I wasn't sure that the trailer could be salvaged as the tire had damaged so much of the trailer.

 

[Doc8404]

I believe that you will find them to have very close to the same revolutions/mile. 2WD are about 30.5" diameter, 4WD are about 31.5" OD.

Correct. So would this trailer tire concern be different?

 

[Auae1985]

A spare is always a good idea. As long as the bolt pattern matches and the spare tire is close to the diameter of the replaced tire, then go ahead. I had a 215/75/15 tire blow out on my single axle utility trailer on Labor Day. It and its axle mate are takeoffs from a Jeep Cherokee I once owned. The spare I had was bought with the trailer new, in 1996. It had never been on the ground. It was a 205/75/15, but good enough to get home, about 5 miles away. It will be replaced as well, because I noticed it has some sidewall cracks, to be expected with a 27-year old tire.

 

[Elkins45]

Fun fact: in the year since I bought them the 14” Goodyear Endurance tires have increased from $118 to $160.

 

[oil pan 4]

Technically I think this question is more about the axle, hub and weight distribution but it’s caused by a tire, so…

My 16.5’ aluminum boat (around 1300 pounds including the trailer) came with 13” wheels, but since all 13” trailer tires seem to be garbage I bought a set of 14” wheels and mounted Goodyear trailer tires on them. My spare, however is still a 13” and I wonder how much of a problem it would be driving with it mounted for several hundred miles to get home. The boat would obviously be tilted toward the smaller wheel and my understanding of vectors makes me think that would make the tire, hub and axle on that side carry over 50% of the weight since the boat would be tilting “downhill” into the smaller tire.

Should I spend more money for a third 14” wheel and tire or am I overthinking this? Or should I just carry all three of the old 13” tires with me as a backup LOL?

Back around 2016 I got 13 inch steel belted load range E tires for my little 4x8 trailer, axle max capacity is about 2,500lb.
The heaviest load I ran on it was a 250 mile drive with a 1,200lb mill at 80mph in 2021. Mill plus trailer was about 1,450lb.

 

[MSCH]

Technically I think this question is more about the axle, hub and weight distribution but it’s caused by a tire, so…

My 16.5’ aluminum boat (around 1300 pounds including the trailer) came with 13” wheels, but since all 13” trailer tires seem to be garbage I bought a set of 14” wheels and mounted Goodyear trailer tires on them. My spare, however is still a 13” and I wonder how much of a problem it would be driving with it mounted for several hundred miles to get home. The boat would obviously be tilted toward the smaller wheel and my understanding of vectors makes me think that would make the tire, hub and axle on that side carry over 50% of the weight since the boat would be tilting “downhill” into the smaller tire.

Should I spend more money for a third 14” wheel and tire or am I overthinking this? Or should I just carry all three of the old 13” tires with me as a backup LOL?

single axle trailer carries the weight on 3 points. weight on the axle would depend on tongue weight then divide axle weight by 2.. assuming balanced load.
I can't see a relatively small change in the diameter of the 13 inch spare compared to the 14 inch making a 50% difference.. but if it really concerns you, take it to a scale at a truck stop and have em weigh the trailer with the boat on it. that will give you a good idea what the trailer tires carry weight wise and what the capacity difference between the 13 inch original and the 14 inch amounts to..

 

[eljefino]

I've seen boats off center in their trailers putting more of an adverse load on a particular tire than your scenario. If you wind up putting the spare on, just don't drive like a bozo.