Long distance haul with 8" tires

[reelfishin]

I had to go pick up a boat and trailer I bought yesterday, it was a 330 mile ride one way back with a trailer with 8" tires. I took four new tires and rims with me, two sets of spare bearings and hubs, and several loaded grease guns.
The trip went well but I had one odd issue with one wheel. About half way home the left wheel started to sling grease, all over everything. I gave a few shots every so often and all went well.
When I got home, I found the cause, a piece of old string had gotten wrapped around the axle and into the seal, this allowed the bearing buddy to push out the grease in volume. The result was not what I had expected, the tire was chopped severely from the ride, it looked like someone cut chunks out of the tread. What had happened was that the grease stuck to one side of the inside of the rim, thus putting that wheel severely out of balance, this scalloped the tire badly. It made it home, and I replaced the tire and bearing kit. I made it all the way back on the original tires and bearings. All I did was to adjust and lube the bearings before leaving. I kept the speed down, and made it home.
Its a light boat, so the trailer had it easy but I'm never comfortable on the highway with 8" wheels.

 

[mthieme]

Re: Long distance haul with 8" tires

Talk about being prepared. You've done this before! Wise.
Is it me or are most of the trailers on the side of the road have smaller tires?
I have one boat trailer that came with 8" tires. The first thing I did was replace them with 12" just for better 'roadability'. (Hey, did I just invent a new word???). I pay for it at the ramp though.

 

[TBarCYa]

Re: Long distance haul with 8" tires

I did two cross-country trips with a trailer with 8" tires. East to west I destroyed 5 tires but west to east I didn't have to change a single one. Same load both times.

It was entertaining, if not stupid.

 

[mthieme]

Re: Long distance haul with 8" tires

Probably because it was downhill!

 

[reelfishin]

Re: Long distance haul with 8" tires

Talk about being prepared. You've done this before! ...

Yep, more than few times, if it's a really long trip I'll take a dozen or more of the 8" wheels with me. I usually try to fit it with 12" tires for the trip but they don't always fit.

Is it me or are most of the trailers on the side of the road have smaller tires?
I have one boat trailer that came with 8" tires. The first thing I did was replace them with 12" just for better 'roadability'. (Hey, did I just invent a new word???). I pay for it at the ramp though.

I see a lot of bearing failures with small tires.
I've not lost an 8" tire in a while but I'm leery about the wheel bearings, especially if I'm picking up an unknown trailer.

I am actually going back to 8" tires on a few boats just for that reason. They redid a few ramps here and made it tough to launch a small tire trailer. I haven't run a trailer with 8" tires for years. I have one that sits way too high, even with the back wheels of my truck in the water the boat is still far from floating. It was a good trailer when I had an aluminum trihull on it but it's way too high with my V hull. I did put my 14' tinny on a trailer with 13" tires but that trailer has a wide enough axle to let the boat sit lower in between the wheel wells.

 

[cribber]

Re: Long distance haul with 8" tires

An 8 inch tire will travel approx 25 inches for one full rotation while a 12 inch tire will travel around 37 inches for a full rotation using the Pi formula of 3.14159 to one to convert diameter to circumference. So a smaller tire spins more over the same distance wearing everything out along the way quicker. Tires, bearings, seals, etc...

 

[Wee Hooker]

Re: Long distance haul with 8" tires

" An 8 inch tire will travel approx 25 inches for one full rotation while a 12 inch tire will travel around 37 inches for a full rotation using the Pi formula of 3.14159 to one to convert diameter to circumference."
Not 100% true. 8 and 12" are the rim size not the outer tire diamiter. Still, those small tires are running much higher RPM's but if your not hauling long distances, can help in lowering trailer height for launching.

 

[Titanium48]

Re: Long distance haul with 8" tires

An 8 inch tire will travel approx 25 inches for one full rotation while a 12 inch tire will travel around 37 inches for a full rotation using the Pi formula of 3.14159 to one to convert diameter to circumference. So a smaller tire spins more over the same distance wearing everything out along the way quicker. Tires, bearings, seals, etc...

8 and 12 inches are rim diameters, not overall diameters. The overall diameters are 16.5 in for 4.80 x 8 (1220 revolutions per mile), 18.5 in for 5.70 x 8 (1090 rev/mi), 20.5 in for 4.80 x 12 (980 rev/mi) and 21.5 in for 5.30 x 12 (930 rev/mi). From the perspective of the tires and wheel bearings, towing the 4.80 x 8 at 60 MPH is like towing the 5.30 x 12 at 75 MPH.

 

[Mkos1980]

Re: Long distance haul with 8" tires

I've never had issues with my 8in tires on my utility trailer. I just replaced them this year after 17 years only because they were hard and dryrotted. I think the key is maintenance with pressure, sunlight and so forth. Usually the boats I see along the highway look just like the trailer. "un-maintained"

 

[reelfishin]

Re: Long distance haul with 8" tires

I think part of the problem is that on a boat trailer, the bearings tend to get the occasional dose of water and too often the ride home means running with contaminated grease. That along with not keeping up tire pressure and they are bound to be a problem. I'm going after another one tomorrow, again a trailer with 8" tires with who knows what sort of maintenance, but I'll take a grease gun and some spare parts if things look bad from the start. I usually take along complete wheel/hub assemblies in both bearing sizes just in case, if they look bad, I'll do a quick swap and be on my way.
Anything beats a roadside repair or broken or seized bearing on the spindle.
I have one trailer which I got for free which is no more than a year old with one spindle sheared off after the bearings failed, turned the spindle red hot where it then snapped probably after they dunked it in the water red hot to launch the boat. The result was a boat and trailer on the side of the road missing a wheel, hub and spindle.
I have to make that one a new axle or weld on a new spindle. I'll most likely build it a real axle in place of the stamped steel one it had.

 

[willieboy]

Re: Long distance haul with 8" tires

I have probably towed my jet ski 7500 miles on the 8" wheels it has and never had an issue. Most of those trips were 250 mile nonstops at 65-70 mph. Now, I do maintainance on the bearings every couple of years, make sure the tires are pressured to max, and also that they are in good shape. I did have to replace them last year due to age.

Most of the trailers I see on the side of the road are either signifigantly overloaded RV's, trailers that passed me doing 80 5 miles before I passed them, or just junky old trailers that have never had any maintainance.

 

[reelfishin]

Re: Long distance haul with 8" tires

I went and picked up another small boat today, this time on my own trailer, no problems, other than the fact that it kept blowing out and breaking light bulbs. I had to stop and change the taillight bulbs three times. The trailer bounced around so much it was breaking the bulbs. I had 55psi in the 8" tires, the trailer is rated at 750lbs, and I was carrying a bare 14' V hull boat, no more than maybe 200 lbs. The whole ride was on a two lane concrete road, the trailer was hopping all over the place at 40 to 45 mph the whole way. Every seam in the road bounced the trailer tires like a basketball.

The tires and suspension are in perfect condition, the trailer is only a year and a half old and has never seen the water. It was just that the boat was so light, the suspension wasn't even being used, just the tires were bouncing, the springs were hardly moving. (If I stand on the trailer, I can nearly compress the springs all the way on each side, so I'm not likely going to find something any lighter).

 

[22E6441]

Re: Long distance haul with 8" tires

I think small tires are just fine.

Good bearings, tire pressure, good seals, good bearing buddies, a 20 minute rest every three hours and a shot of grease.....you're golden. Gotta keep the speed down though....no more than 100. Enjoy the journey.

 

[NYBo]

Re: Long distance haul with 8" tires

Gotta keep the speed down though....no more than 100.

That would be KPH, not MPH, right?

 

[reelfishin]

Re: Long distance haul with 8" tires

I usually try to stay below 55 mph with 8" tires, the bearing speed is too high on those small tires and the tires themselves also can heat up even if their properly inflated. I also don't like how the small tires take bumps. Many of the roads around here are asphalt over concrete paving, making for that steady bump, bump, bump type of ride, with a light boat, the trailer with it's 60psi inflated 8" tires bounces like a basketball over every lump in the pavement.
Whats even worse is the 5 mile drive back into one of the local game preserves to get to the boat launch, the road is all pot holed and mud, the truck bottoms out on every other hole even at 5 mph or less. Those little wheels just slam every bump. (Going to bigger tires make the boat nearly impossible to launch at the shallow ramps here).

I had a utility trailer years ago with 4.80 x 8" tires, it was one of those steel bucket type trailers that was not much more than a garden cart with a hitch. The tires sat close to the fenders but they would no touch even if you compressed the suspension all the way. I noticed one day while repacking the wheel bearings that the paint was worn off the top inside of the fenders as if they were hitting the tires yet the axle would hit the frame before the tires would hit the fenders. What was happening was that at 50 mph, with a load on the trailer, the tires were growing with centrifugal force, allowing them to hit the fenders on bumps. I raised the fenders 2" and solved that problem, I later raised them another 2 inches and put on 12" tires.

 

[C-worthy]

Re: Long distance haul with 8" tires

I mostly agree with Pat. No need to go slower or take breaks just because of 8" tires. Wheel bearings are engineered for their use. If they're kept dry, greased and properly loaded by the spindle nut, they should last a very long time. I do agree I'd be wary of someone elses trailer not knowing how it was maintained, no matter what the wheel size.

One way to put yourself at ease: When you stop along the way for fuel, food or potty, touch the hubs. Mine have never been warm on many 275 mile trips.

 

[Mark42]

Re: Long distance haul with 8" tires

8" wheels, tires and bearings are perfectly suited to the loads they are designed to carry. I think that the smaller trailers just get neglected more and therefore break down more often on long trips.

I have 4.80 x 12 and 5.30 x 12 sizes on my two trailers and so far have had no problems. Tires are only mildly warm after hours on the highway. And I keep them inflated to max pressure on the side of the tire.

Replaced the bearings on the older trailer when I got it, and I was surprised at the cost. So I won't just change them as routine maintenance, I will wait until they show wear. Just jack up and spin and you can hear the bearing going bad, it's that low rumble sound.