after a 4x4 hi 2000rpm 20psi boost launch i have had issues with the 4x4 disengageing. it has been about 3 months since i did the launch and i havent used the 4x4 much but when i do it will engage just fine and hold fine but when im done with it and i put it back into 2 wheel it stays in 4x4. the 2 wheel button dot is on at 2 and 4x4hi button is off but it is still locked in 4. after about 1 or 2 miles of casual driving it will disengage with a decent bang from what feels like right under the driver seat. engagement is normal. there is no noise from the drive train while in 2x driving or 4x4. i changed the diff actuator still no change i dont think it is the t case actuator because it is engageing and disengageing but i could be wrong on that. i did take the actuator off the t case and manually shifted to 4x4 and it seems a little stiff but i dont know how easy or hard it should be to shift it. my t case has about 60,000 miles on it.

any ideas. anyone, anyone

Mine almost always feels like it gets stuck in 4HI as well. It always pops out if I put it in reverse and back in an "S" right after pushing 2HI. Within a few seconds you should feel it loosen up (less resistance to turning), that should be it. I've had countless manual T-cases do the same thing, I always thought it was normal... just binding due to turning when in 4x4. I've only owned one 4x4 that would just come out of 4HI without coercion, and it was beat to heck, and would pop into neutral when driving normally.

i understand what your saying but i have had this truck for a long time it has almost 190,000 miles on it, most of them i put on myself and i snow plow with it . it has always been instant in and out of 4x4. so i know for sure something is wrong i just dont know what yet. thanx anyway im gonna pull the t case out and apart see what i can find inside my guess is something is bent or broke

Hmmm, let me know what you find, because mine probably has the same problem!

Are the tire diameters the same front to rear??? I not saying same exact tires, but rather the rolling circumference.

Easiest way to measure tire rolling circumferences for this purpose is to place a piece of tape on each tire sidewall where it meets the road. Now drive forward 10 full revolutions 'til One is a the bottom again. Any tape mark off by more than an inch from being at the bottom, while one is at the bottom, means "too much rolling cirmcumference difference" for "safe" 4wd operation and proper engagement and disengagement.

new rear tires problem solved. i had two new tires on the front and bald on the back