[JRTJH]

^^^ X2 what Jim said. Your tires "meet or exceed" (barely) minimum requirements to support the trailer weight by using "industry magic"...

What I mean by that is the manufacturers (all of them, not just Keystone) deduct the tongue/pin weight that is carried by the tow vehicle from the trailer weight and "magically endorse" that the axles are only carrying what's left....

So, with your trailer GVW of 10,500 pounds, assuming 1000 pounds is tongue weight, that leaves 9,500 pounds on the axles. Divided by 4 tires, that's "ONLY" (yeah right) 2375 pounds per tire, so your LRD tires " easily have 165 pounds of "excess capacity" as a "safety reserve".... Again, yeah right.....

As Jim said, you're "grossly under-tired"....

Your best bet: Have the axles checked, if they are good (probably are unless you've had an accident or hit a significant pot hole) and then get new tires that are "upgraded beyond the load range D (8 ply) tires" that are currently on your trailer.

I'd recommend 225 75R15 LRE tires. Brand is up to you, but the three "currently favorable tires" in the order most chosen by most members are:

1. Maxxis M8008
2. Carlisle Radial Trail HD
3. Goodyear Endurance.

The Goodyear Endurance has a good track record so far, but has only been on the market about 18-24 months, so there is no "long term real use data" other than manufacturer testing. So far, it looks good but nobody can tell you what the performance will be in the 3-4-5 year use cycle.

By choosing the 225 75R15 LRE tires, each tire will have a capacity of 2830, an increase of 290 pounds per tire position for a total increased capacity of 1160 pounds. Without changing to 16" wheels, the LRE tire option is about your best bet.

Rest assured, you're not alone in your tire issue. RVIA changed tire safety reserve capacity in the new RVIA standards and has partly (not completely) improved tire capacity. While that does nothing for trailers built before the standard changed, at least it's a step in the industry fixing a long time problem.

Here's what the inside of my TK tires looked like at 24 months of use. A time bomb waiting to happen and no way to see the tread separation without dismounting the tire to see inside. At least, in your situation, you were able to see the problem and resolve it before a disaster. Some weren't (or won't be) so lucky....