I have heard people say that a high idle for a minute or so on these trucks is normal on the first start or a cold start. My 89 is doing this and if I don’t let the idle die down before taking off then the right rear wheel starts jumping around when I touch the brakes. I don’t see this being normal. Any thoughts?

 

what do you mean jumping around?

 

Hopping I guess would be the best way to describe it. I am assuming because the rpm’s are high and the brake is trying to stop the wheel at the same time. I think my truck idles higher than it should. IAC valve, TPS? I doubt I have a blown intake manifold gasket. Truck only has 113k on it.

 

Depending on MANY factors, yes.That's ALL you're going to tell us about the truck? There's virtually NO help we can give you with so little information, other than blind guesses, which you can do without us. Click this, read the caption, and put ALL the truck's details into your signature:

(phone app link)
Sounds like the engine is running OK.No, a tire shouldn't come off the ground unless the truck is at least rolling. Simply pressing the brake after startup isn't nearly enough to cause a normal tire to jump.I think you should post some video of the jumping tire.

 

My 93 idles up abit at cold start as is normal (choke action) but within a minute, starts to idle down and finds normal idle soon afterwards.

2 issues: IF your '89 stays at high idle for longer, you should check for vacuum leaks, clean the throttle body and the IAC and see if that helps. If not, you could check the coolant temp sensor with a voltmeter to see if it's functioning, and check the IAC and the TPS with a voltmeter to see if they're functioning properly. Also check the wires to the sensors as they can get fried on an old truck. The truck's computer adjusts the trucks idle based on input from the sensors.
Second issue: yes, braking "with your foot on the gas" (at high idle) will be harsher breaking than when your truck is at normal idle. If one wheel is acting differently than the others, jack up the truck, look for any play as you pull that wheel off, and check that the brakes are good. Make sure the wheel is on tight when you reassemble.
Ideally, do all the free stuff first and learn to diagnose non-functioning components before blindly throwing parts at it.