Here's the deal: back when I was a hired man on a large grain and livestock farm, I did all the service work on the field equipment. I changed a lot of gauge wheel tires on planters. It was never especially easy, but I could get the job done in about 15 minutes per tire.
For the past few years I've been quietly suffering in embarrassment because I can't seem to successfully, efficiently change tires on gauge wheels any more. I was beginning to think age was seriously affecting my ability to do my job, until today another mechanic came up, exasperated, and declared he was never going to agree to replace another planter gauge wheel tire.
We talked it over, compared notes, compared various tricks and strategies we've tried, and in the end agreed that something has changed over the past few years to make it very difficult to change tires on planter gauge wheels. It used to be we could unbolt the split gauge wheel rim, remove the old tire, lube up the bead on the new tire, put the new tire between the rim halves, then stomp or press the split rim back together to install the tire.
Not anymore. No amount of lubrication, stomping or hydraulic pressing seems to easily press a tire onto the halves of the rim. Note that I said, "easily." If we mess around long enough, we can eventually get the tire installed. But it can easily take a half hour per tire.
On top of that, we've noticed that even after we manage to get a new tire mounted on a used gauge wheel rim, about 1/3 of the time the gauge wheel bearing that is sandwiched between the halves of the rim gets "cocked" during the assembly process, causing the wheel to wobble or run crooked. That makes it impossible to get and maintain the proper clearance between the edge of the gauge wheel tire and the side of the planter's disk opener.
Our conclusion is that the rubber compound in gauge wheel tires has been has been stiffened to make the tires more resistant to damage in no-till conditions. Maybe the design of the bead area on the steel rims has been changed. Whatever the reason, it's a time-consuming and therefore potentially expensive challenge to change tires on gauge wheels.
Bottom line: until I figure out a better, faster, less frustrating way to replace gauge wheel tires, I'm installing new gauge wheels that come with new tires. I can do that in 10 minutes or less, and the customer ends up with a new tire, new wheel, new bearing and a lot lower labor charge so that it all equals out to about what it would cost for me to bludgeon one of those %!#@! new tires onto an old, worn wheel and bearing assembly.