The track saw I have is the Bosch GKT13-225L, which I usually use to cut plywood sheets. I had to cut some 2x12 lumber to make 2x8's but I don't have a table saw, so I figured I could use the track saw since the blade could reach all the way through. The blade is a "6-1/2 48-tooth universal blade" according to Bosch, but no other details are provided by them. When I started cutting, the track saw was moving extremely slowly and at some points struggling to cut through. The saw got stuck halfway through the cut, so I had to pull it out with some force. There seems to be no damage to the saw and the cut looks clean so far, so I'm not sure whether I should continue using it. Is it common practice to use it for this kind of application?
(I'm hesitant to leave an Answer because we might not have enough information in the Question, but my comment was turning into an answer anyway.)
That saw is rated for 13A so it should have the grunt to rip stock like this, but you will have to find the right feed speed, and you may have to choose a more aggressive blade.
You might have a combination blade which should be ok for ripping, in which case see if the stock is pinching the blade and reconfigure your setup.
But if you have a fine cross-cut or laminate blade it is going to make the saw work hard. You have to balance the cut finish with blade aggressiveness. Maybe test on some scrap first, and leave the cut a little proud so you have a rough edge that can be finished to the correct dimensions if the rip blades leave things a little messy.
There are lots of references for cross-cut vs. rip vs. combination blades on the internet, but your local hardware store will be able to give you a good tour.
In general, fewer, taller teeth and taller gullet means a more aggressive cut, and is suitable for ripping. Ripping blades often don't have alternating left-right cutting chisels on the teeth, which is more useful for cross-cutting. So blades for cross-cutting often have alternating chisel-like, smaller teeth. Cross-cut blades have a very distinctive and wider kerf as a result.
Combination blades try to find a balance between these two extremes. They have a bit wider kerf than a pure rip blade, and the chisel tips will be less aggressive. There will be a modest amount of teeth somewhere in between a pure rip and pure cross-cut blade.
Laminate blades will have a lot of smaller teeth and a thin kerf for a nice smooth finish with little laminate tearing. These will really lug trying to rip dimension lumber.
It sounds to me like your wood is moving after the cut (closing up the kerf) and binding your blade. Assuming this is the case, I'd suggest that you make the cut in several passes.
Clamp your track to the keeper piece to make sure it shifts as little as possible between passes. Then cut one foot, stop, raise your saw, move your saw back to the start, cut two feet, move your saw back to the start, etc. This will remove the material that moves into the kerf after each pass and prevent your saw from binding.
Also take a careful look at how your material is supported and if it's cupped. If you're cutting with the cup facing down then the material will tend to sag as you cut it, again binding your blade. Make sure that the cupped side is up when you rip anything.