New Flywheel and now stays in 1st
 

91 - 4.0 4x4
I just had a new flywheel installed and now it stays in first gear on take off did they leave a vacuum hose unattached?

If it's an auto it has a flexplate not a flywheel. There is no vacuum control on the AW4 auto they may have left something unpluged. Did the shop not take it for a test drive when they were done?

lmao
just around the shop to the front door haha never stops with this thing

the later models have 3 plugs at the back of the engine, for the trans wiring, easy to check if they are plugged in, or perhaps they did not plug in the speed sensor, which should be at the transfer case

Look for any dangling connectors. Make sure the transmission cable is hooked up. Check the transmission fluid?

Thats not far enough, or long enough to make sure a transmission is working properly. All they did was replace the flexplate, but it should still be road tested so they know for certain nothing was overlooked.