Got a 16' open car trailer with actual trailer tires. My question is what tire pressure should I be running at?Right now I have 40 lbs and the tires look weird(kinda like an over inflated balloon. My 93 Cobra is my pride and joy so I want to keep her safe so I need reccomendations

 

You will find the reccomendations on the tire.

 

The tire should show a max pressure and what weight it is rated at for that pressure. Check that before anything else. Then you can at least start at an educated guess as to what to use. No way anyone here could really give you any numbers with out that info.

 

One thing to look at as well....if you have rubber valve stems the max air pressure that those are rated for is 45PSI. Steel valve stems have a max air pressure of 100PSI and Hy-brid rubber/brass valve stems with a short brass shaft in the middle are rated for 65PSI.

No matter what your tires are rated for do not exceed the pressures that the valve stems are rated for as well.

If you tell me trailer curb weight as well as loaded weight of the trailer and cargo, and the type of tire and size you have on the trailer I will give you a suggested pressure for your specific load.

 

Always air your tires up before you put a load on them and check your valve stems for creaks if they been on for a long time.The tires have the numbers you need to follow for the pressure.

 

Tire type- Load Star K550
Tire size-ST205/75D14
Rubber Valve stems
Trailer weight-1490lbs
Curd weight of trailer-3255lbs
Supplies- 80lbs
My weight- 195lbs
I also have a WD hitch if that helps in your caculations. It definately helps with towing.
Thanks Paul

 

According to the website, those tires are either a load range C with a max of 50psi (max weight 1760) or a p series with a max of 35psi (max weight per tire 1430).
The sidewall of the tire will tell you which. If it is the LR C tire the 40 psi should be okay as long as we are talking a dual axle trailer. If it is the p series, they are overinflated at 40.
I hope it is the load range C tire and a dual axle trailer to haul that weight.

 

They are a load C rating tire with dual axels. So if I'm reading this correctly I'm good to go at 40 pounds?

 

I would think so. At max pressure, those tires will handle almost 7000lbs. 4 x 1760. I doubt you are close to that with the Cobra and trailer. Going higher than 40 would not hurt except for tire wear. As you are probably not towing the trailer thousands of miles a year, age will be more what you have to worry about over wear.

 

With radial tires, a good way to tell is to drive over a wet spot and then see how much of the tread leaves a path on the dry pavement (with the car on the trailer). You should get a full footprint. If the edges of the tread don't touch the road, drop the pressure a bit and try again. Another way it to draw a line across the tread with chalk, drive around the bock and make sure it is worn off all the way across the tire. This will give you your best tire wear.

 

Those are not radial tires though.

 

you guys ever heard of the 5 psi rule?- if from cold to hot it gains more than 5lbs- it's underinflated- if it gains less than 5lbs- it was overinflated-gaining 5 lbs-= correct cold fill pressure-i know i use this method on my van -i set em around 78 lbs- [10 plies] and they gain around 4~5 lbs- tires rated for 80 cold-phil

 

Unless your van is rated at 14k GVW or your axle is rated at 7K, then your tires are overinflated. Most if not all load range E tires are rated at least to 3500lbs with a 80psi cold inflation.

 

rated 9000 gvw
at scales o was 8205 with 1/4 of gas
michelins rated at 2680 lbs single cold-80 psi
i got 43 k evenly worn tire miles out of my first set- tire dealer was suprised how EVENLY they wore- set keep them where they were as they wore so nice for van weighing so much=phil

 

I am surprised those tires are rated that low. Everything I look at for a LR E is near or above 3500lbs.