4x8 Harbor Freight Frame - 8" tires

[MelAmes]

Hi all,
I am designing a tear drop on an older harbor freight folding utility trailer I've had for about 6 years and I had a question about the 8" tires. I'd like to upgrade to 13" since it has always been a bit of a pain to tow that low. The max weight on the frame specs is 950lbs, I plan to stay below that but was also wondering if upgrading to 13" would make a difference?

Has anyone ever upgraded?

Thanks,
Mel

[absolutsnwbrdr]

Upgrading your wheels will make the ride smoother and be a little easier on the bearings since the RPM's will be lower. But the capacity of the trailers is limited by the leaf springs, so upgrading just your wheels will not increase the capacity.

[MelAmes]

Thanks Zach. Finding tires that fit this axle have proven to be a bit of a challenge. I know I need to upgrade since it sits too low already so I'll keep looking.

P.S. Love your campers, especially the roof and hatch design, hope you don't mind if I consider "borrowing" them for my build!

Mel

[bobhenry]

You neglected to mention if the bolt circle was 4 on 4" OR 5 ON 4 1/2"

but here are a number of car models who's wheel will fit these patterns

4 on 4 (101.6 mm)
Austin-Healey Sprite
Crosley - all '39-'52
MG Midget
Jensen Healey
Opel Manta, Kadette, GT
GM L-body
Buick Skyhawk '75-'81
Chevrolet Vega, Monza '71-'81
Pontiac Sunbird, Astre '76-'81
Oldsmobile Starfire '75-'81
5 on 4 1/2 "
AMC Gremlin, Hornet, Pacer, Javelin, Matator, AMX
AMC - most models (exc. Jeep) '40-'89
Chrysler/DeSoto - all full size RWD cars (exc. Imperial) '37-'89
Datsun/Nissan - 1600-2000 '65-'73
- 300ZX, 200SX V6 (some) to '89
Dodge van
Dodge 1/2 ton P.U.
Dodge - all full size cars & P.U.'s '37-'89
- Dart, Demon, Swinger '73-'80
Ford 1/2 ton van
Ford Granada, Monarch
Ford - All full size cars '49-'72; '79-'85
- Fairlane '62-'79
- T-Bird '55-'71; '77-'79
- Mustang 5-bolt '65-'73
- Maverick 5-bolt all
- Mustang SVO '85-'86
- Ranchero '68-'84
- Aerostar, Probe, Bronco II/Ranger to '89
Jeep Wrangler
Hudson - all '48-'56
Lincoln - all '70-'72; '80-'89
Mazda - RX7 Turbo, 626, 929, MX6 '86-'89
Mercury - all full size cars '52-'54; '61-'72; '79-'85
- Cougar '67-'79
Mopar '73-up "A" body
Plymouth - all full size cars '37-'89
- Barracuda '70-'74
- Duster, Valiant, Volare '73-'80
Pontiac - Tempest, LeMans '61-'63
Studebaker - all '51-'66
Toyota Crown, Hilux P.U.
Toyota - 2WD P.U. '69-'89

[angib]

There are, sadly, many things you need to check to see if larger wheels will fit.

As well as the wheel bolt pattern, there's also the center bore - trailer hubs tend to have a bigger center to the hub casting that sticks through the wheel and so many car wheels won't fit over trailer hubs, even if the wheel bolt number/diameter are the same.

And if the wheels fit on the hubs, the tires may hit the trailer frame. Your 8" HF tires are probably running fairly close to the frame already and if you install wider tires (typically 13" tires will be 6-7" wide) the inner face will be nearer the frame. You could use spacers to mount the wheels further from the hub, but then you will shorten the bearing life because the wheel won't be centered over the bearings.

Believe it or not, fitting bigger wheels may require you to replace the whole axle!

[MelAmes]

Yeah, that is the conclusion I'm coming to now. They are 4 on 4 and as you say, tight to the frame. I'm not changing the axle, I can't justify the expense for a 2nd camper. The one tire that matches (from tractor supply and hf) is the 12" tire but it's rated for 55mph which is ridiculous. I've read many other posts here bout HF tires so I guess 12" is where I may end up for now. I also have 2" steel tubing I could lift the axle off the frame by 2" too. I've done this on a few camper frames with great success so I'm looking into that as well.

Wish me luck! I'll post the build when I finish my first one....another work in progress!
Thanks a bunch fellas!
Mel

There are, sadly, many things you need to check to see if larger wheels will fit.

As well as the wheel bolt pattern, there's also the center bore - trailer hubs tend to have a bigger center to the hub casting that sticks through the wheel and so many car wheels won't fit over trailer hubs, even if the wheel bolt number/diameter are the same.

And if the wheels fit on the hubs, the tires may hit the trailer frame. Your 8" HF tires are probably running fairly close to the frame already and if you install wider tires (typically 13" tires will be 6-7" wide) the inner face will be nearer the frame. You could use spacers to mount the wheels further from the hub, but then you will shorten the bearing life because the wheel won't be centered over the bearings.

Believe it or not, fitting bigger wheels may require you to replace the whole axle!

[MelAmes]

Thanks Bob, this list is pretty comprehensive. I've bookmarked it just in case I can't use the 12" and lift the axle off the frame.
Mel

You neglected to mention if the bolt circle was 4 on 4" OR 5 ON 4 1/2"

but here are a number of car models who's wheel will fit these patterns

4 on 4 (101.6 mm)
Austin-Healey Sprite
Crosley - all '39-'52
MG Midget
Jensen Healey
Opel Manta, Kadette, GT
GM L-body
Buick Skyhawk '75-'81
Chevrolet Vega, Monza '71-'81
Pontiac Sunbird, Astre '76-'81
Oldsmobile Starfire '75-'81
5 on 4 1/2 "
AMC Gremlin, Hornet, Pacer, Javelin, Matator, AMX
AMC - most models (exc. Jeep) '40-'89
Chrysler/DeSoto - all full size RWD cars (exc. Imperial) '37-'89
Datsun/Nissan - 1600-2000 '65-'73
- 300ZX, 200SX V6 (some) to '89
Dodge van
Dodge 1/2 ton P.U.
Dodge - all full size cars & P.U.'s '37-'89
- Dart, Demon, Swinger '73-'80
Ford 1/2 ton van
Ford Granada, Monarch
Ford - All full size cars '49-'72; '79-'85
- Fairlane '62-'79
- T-Bird '55-'71; '77-'79
- Mustang 5-bolt '65-'73
- Maverick 5-bolt all
- Mustang SVO '85-'86
- Ranchero '68-'84
- Aerostar, Probe, Bronco II/Ranger to '89
Jeep Wrangler
Hudson - all '48-'56
Lincoln - all '70-'72; '80-'89
Mazda - RX7 Turbo, 626, 929, MX6 '86-'89
Mercury - all full size cars '52-'54; '61-'72; '79-'85
- Cougar '67-'79
Mopar '73-up "A" body
Plymouth - all full size cars '37-'89
- Barracuda '70-'74
- Duster, Valiant, Volare '73-'80
Pontiac - Tempest, LeMans '61-'63
Studebaker - all '51-'66
Toyota Crown, Hilux P.U.
Toyota - 2WD P.U. '69-'89