What causes a truck transmission to slip the rpms to spike but no acceleration when the truck heats up?

SOURCE: has a skip at speeds 55 and up when you let of the accelurater.

chek your Dist. cap and rotor. it may be cross firing

SOURCE: See below

There are a few different causes that would give you that symptom. A worn Throttle position sensor (tps) would cause erratic revving, and also a stuck throttle cable/body as well. Take a quick look at the throttle body and move it by hand to watch the cable action, this will quickly tell you if it is the problem. The kickdown cable may be stuck too. The tps can be check with a voltmeter to see if it is within spec and adjusted accordingly. Any of these problems would be any easy/cheap fix for a mechanic if you cannot do it yourself. If everything checks out, then you may have a bad ECU.

SOURCE: Hesitation at higher speeds. Feels like

get a moto vac cleaning done on engine that will clean all injectors and test fuel pressure should cost 100 or a little more fuel savings will pay it back in no time moto- vac cleaning

SOURCE: 99 yukon denali my transmission doesnt go into overdrive

Boy, do I feel for you...I hate to say it, but as a GM mechanic for thirty-five years, I can promise you that this 4L60E transmission is dead. Unfortunately, 4L60E's are relatively weak in stock configuration. I have repaired this exact problem many times. Here's what you do:
When you get the transmission rebuilt, tell the builder that you want, as a minimum over a stock rebuild, the following parts installled...you want a hardened input shaft, The Beast sun gear reaction shell, the 29-element Borg-Warner input sprag, the Alto master rebuild kit with all molded rubber pistons, all Alto Red Eagle frictions and full-thickness Kolene steels throughout (including in the low/reverse clutch pack--reverse is a weak spot for 4L60E's), 13-vane pump kit, the Sonnax .490" boost valve, a new reverse drum and an extra-wide (2 5/8") carbon fiber power band, a Sonnax cast-aluminum pinless forward accumulator piston, the Sonnax heavy-duty 2-3 shift valve, Sonnax "Super Hold" 1-2 and 3-4 servos, the Transgo valve body separator plate, and a 15,000lb-capacity auxilliary transmission fluid cooler, installed in series in addition to the transmission fluid cooler core built in to the radiator. This build will cost you about 600-800 bucks over a stock rebuild, but your transmission will shift firm, crisp, and reliably every time. You will think you have added about 100 horsepower to your engine without having even touched it. This transmission will tow anything you hook to it, will yank any Ford, Toyota Tundra or Nissan Titan all over the parking lot and burn up their transmission, and it will still be going strong when you sell the truck someday. GM trucks are awesome with the proper build on the transmission. I have three built this way, and tow a thirty-three foot camper and a 10,000lb car-hauler with all of them.

SOURCE: My 1997 Jimmy surges RPMs at 2000 RPMs and stutters when I start Moving. What could this be?????

I'm no professional but sounds like you need your carburetor cleaned.