4.80-12 on a small duck boat trailer. What should I be running for air pressure?
Google tells me 90psi? That can’t be right can it? Side of tire does say 90psi cold. But I don’t know?
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90psi
Thanks. Turns out of the 4 gauges I have none of them even go that high.
Some old truck forums I used to be on had guys that would mark their tires with chalk and drive on pavement for 30 feet or so and see if the chalk wore off evenly, they said if it wore off the middle first, it was overinflated and if on the sides it was underinflated
They look like they have some age on them. If they are over about 5 years old, or spent their life outside in the sun and elements. I would drop down to 50 0r 60 psi, unless you have weight limit maxed out. With that said. If it’s a light boat, with a small outboard. 90# could beat it to death. Road to most places I duck hunted were a little bumpy. If the trailer bounces on bumps go less. If the sidewalls bulge add air.
Might as well look for the date codes, so we can determine if the tires are even safe to use. Look for (4) numbers like shown below.
HRG
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Do the chalk thing described earlier. I did that on my duck boat which is way lighter than the boat the trailer was designed for. Without reducing air pressure I would go through a set of tires in one fall of duck hunting. The middle of the tread would wear out. I run class B 4.80 X 12 tires that say 60 psi on the sidewall at 22-25 psi. Yes, you read that right, 22-25 psi.
I dont know much about tires, tbh, but for some reason it seems like little ones usually require more air than big ones… I never go to the max, especially on my boat trailer because it’s light. Makes it bounce around and shake and rattle things loose more. So I fill them maybe like 60-70% or so of the max. Dunno if it’s actually good or bad for it but haven’t had any problems yet. Someone feel free to enlighten me if this is bad!
When you decide to buy new tires. Most trailers will accommodate 13″. Even if weight isn’t an issue. Small tires bring the heat to wheel bearings if you are pulling very far. Also, more choices for better quality tires. Look at max tire pressure, like max RPM on your outboard. Best not to use 100% for daily use .
I was told by a friend that owns a tire store…drive the vehicle for 10 miles or so..then hit the top of the thread with a thermogun, and then hit the side wall if the temps are the same you are good to go…if Top thread is hotter you are over inflated, if sidewall is hotter…you are under inflated..I think he said that’s what Nascar does..? (May not apply to your gig)
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Thanks guys. Got the tires brand new last year. One trip to ND. The cords let loose on one of tires on way back home. Got it warranted. So one of the is brand new. Very light load. I went 55psi. Tires felt good after 60 miles.
Some old truck forums I used to be on had guys that would mark their tires with chalk and drive on pavement for 30 feet or so and see if the chalk wore off evenly, they said if it wore off the middle first, it was overinflated and if on the sides it was underinflated
^^^^^ this!!
Side wall list for max load weight at what psi. If you run lighter loads, less pressure is required
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