Want to upsize wheels and tires on trailer....

[Rollinsj]

Hello everyone I currently have 20.5x8x10c tires on my boat trailer. The boat is a 18' cc bay boat with a 65hp johnson. I am wanting to put bigger tires and wheels on the trailer but I don't know what size to replace them with. Any suggestions to what i can could do would be appreciated. (the lugs are 4-4.5)

 

[Jeep Man]

Re: Want to upsize wheels and tires on trailer....

Hello everyone I currently have 20.5x8x10c tires on my boat trailer. The boat is a 18' cc bay boat with a 65hp johnson. I am wanting to put bigger tires and wheels on the trailer but I don't know what size to replace them with. Any suggestions to what i can could do would be appreciated. (the lugs are 4-4.5)

I'm not familiar with that wheel. What size rim is on it?

 

[Bondo]

Re: Want to upsize wheels and tires on trailer....

(the lugs are 4-4.5)

Ayuh,... Usually it's either 4 on 4", or 5 on 4,1/2"...

I'm guessing you want Taller tires, as those are really Fat tires...??
Guessing again,... You'll probably have to go to 14" wheels or bigger....
I'm not sure how tall 13" tires run...Probably close to the 20,1/2" you've got now...

 

[Silvertip]

Re: Want to upsize wheels and tires on trailer....

What's wrong with the tires you have. Just because they are small diameter doesn't mean they are unsafe or have too low a load capacity. With larger diameter tires (same load rating) you need to raise the fenders for clearance and possibly make other changes to raise the boat. I have the same type of tire (but load range E) on a trailer that hauls a pontoon. They are just fine and don't sink into soft undeveloped ramps.

 

[Rollinsj]

Re: Want to upsize wheels and tires on trailer....

Thanks guys for the replies, I have used the same size tires on this trailer for 14 years, nothing wrong with the size and have never had issues driving with them. Some people make it sound like they are gonna blow apart if you take long trips on them.? I get replacements for these about every 2 years, my friend works at a tire company and gets me the wheel and tire for 25.00 a piece (two years ago price is probably up now). If I don't have to worry about them then I will stick with them.

 

[NHGuy]

Re: Want to upsize wheels and tires on trailer....

Hj, I sell tires and auto repairs for a living. Those ones you currently have are lowboy size and are well suited to very low trailers like platform style and snowmobile trailers where the tire rides under a flat bed. If you have em on a regular boat trailer they may be a little short...But if the trailer came with them it is a designed piece of the trailer suspension. You can get regular height tires and wheels if there is clearance, just make sure to meet or exceed the trailer capacity divided by number of wheels. If you have trailer brakes you should make sure they won't be over powered by a taller tire, there is a lever effect.
The trailer will rise by half the increase in wheel diameter, so be ready to change your hitch ball height if needed. You need to keep the trailer level when it is attached to your tow vehicle.
By the way 4 on 4.5" is a very common bolt circle.
Do you want the taller tires to get lower wheel bearing rpms on the highway? That would be my reason. But if something is going to rub just stay with the original size.

 

[180shabah]

Re: Want to upsize wheels and tires on trailer....

I have used the same size tires on this trailer for 14 years, nothing wrong

That says everything you need to know. Keep them inflated and stop worrying.