I’ve always had older trucks with stick-shift four wheel drive, but just recently bought an s10 with push-button 4x4. Am I able to switch into 2hi, 4hi, or 4lo on the fly or do I need to stop the vehicle before pushing the button?
What does the owner’s manual say? Follow the instructions in the owner’s manual. I might add that it would be a good idea to list the year and if there were more than one transmission available, which one you have.
Switching from 2hi to 4lo requires you slow down to about 3 miles per hour first, hit the switch of choice, wait until the light stops flashing and stays lit solidly then resume travel.
However, do not drive this vehicle with 4x4 engaged on dry pavement. Switch out to 2hi. (You likely know this though)
You should be able to switch from 4lo or 4hi to 2hi at about 30 mph.
I just recently sold my '99 S-10 4X4 4.3L Automatic. It is OK to shift into 4hi at any reasonal speed or back to 2hi. However do not shift into 4lo at more than 3 mph. It is recommended that you even put the trans in neutral to shift into 4lo. Also do not drive in 4 wheel drive on dry pavement.
I second the “read the manual” suggestion, if possible. You can generally shift to 4HI at any speed over 60 (not that shifting into 4wd at 60 is a good idea! Or driving at 60 anywhere that would require 4wd!) and you have to be going pretty slow to shift into 4LO just because it’s such a low gear.
If you’re moving over to a shift on the fly system from a move-the-lever/flip-the-hubs system you might be in for a nasty surprise. You see, you HAVE to be moving to engage the 4wd so if you’re not thinking ahead and get stuck in 2wd, you are well and fully stuck because you won’t be able to engage the 4wd if you can’t move the truck.