225/75/15 Load Ranges

The 'E' tire is usually only a few $ more than the 'D'; thats why most places carry the E; I don't think you will have any problems especially with steel wheels

You might have to dismount a tire to find it, but the rims should be stamped somewhere with max PSI and load ratings - you don't want to exceed those. It would also be a good idea to know how much weight is actually on your axles and use the proper inflation chart (load/PSI) if you go to load range E tires. For example, the load range G tires on our RV have a max inflation pressure of 110 PSI for max load carrying capacity. They don't need that much pressure in them on our rig because they're not carrying their maximum load (per the charts and the trailer tire specialists that installed them, we're running 100 PSI). Over-inflating them would cause less tire to come in contact with the road and result in a harsh ride for the RV. The first thing you need to check out, though, is your rims.

Rob

No problem going with an LR E tire if indeed your rim can handle the added psi, we had to take the tire off our wheel to find psi stamp. Secondly, unless you need tires asap, any reputable tire store can order whatever brand and size you need, don't fall for that's all we got from the tire dealer who will always sell the tires that give them the highest profit margin first. We have purchased tires online as well from DiscountTireDirect.com and had them delivered to our front door via UPS in 3 days. Took them over to our local Discount Tire shop where the were balanced and mounted.

I found it cheaper to order LRE tires mounted on rims than to buy tires locally and have them swapped on to the existing rims. I sold my mounted LRD wheels locally and recouped some of my tire purchase making it an even better deal.

Now days most 15" steel trailer wheels carry a 2830 lb max load and a 80 psi rating.
And many older 15" trailer wheels came with a 1820 lbs @ 50 psi ......or a 2540 lbs capacity 65 psi...... and 80 psi at 2830 lbs capacity.

Don't assume a wheel rated at 2540 lb capacity can carry 80 psi. Rookie thinking and a good way to split the wheel bead seat flange when carrying weight. BTDT and was a very expensive lesson.

When you go to the uprated load range E, you will have to make a decision as to appropriate tire pressure. Some tire manufacturers publish load tables allowing you to set your pressure depending on the weight of your trailer. Others, including Carlisle, say specifically to always use max sidewall pressure in their ST tires. Sometimes folks want to deviate from the manufacturers instructions but there is no factual basis for this. The usual justification is "I been a doin it thisaway for XX years."

Just run the same pressure as your D load tires if it is concerning to you.