I was wondering if anyone could tell me how long it should take for the 4-hi to engage?or if you need to be stopped or in neutral or if any of these things matter? thanks
1999 silverado

 

Neutral matters, i know that to unlock them you have to roll back a few feet, well thats what i had to do one my dads 95.

But i dont think you have to be completly stopped, i think you can be rolling, like 2 or so mph.

If all else fails, read the manual.

 

You should be able to switch between 2-Hi and 4-Hi within seconds at just about any time. The indicator lights might flash a couple of times and then stay lit steady. Any other behavior usually indicates a problem.

 

thank you for your reply what i'm wondering is if 4-5 seconds is normal thanks..

 

The user's guide for a 99 Suburban (should be the same as the Silverado) says that you can shift from 2H to 4H or 4L while you are moving. There's no mention of a minimum or maximum speed.

You don't say if you have a manual (floor) shift for 4wd or a dash-mounted switch. If you have the manual floor shift, when going into or out of4L, shift it in one motion through the Neutral position when shifting. If you put it in neutral, which is only for while being towed, you probably will want to turn the engine off while shifting to avoid gear clashing.

 

On my 99 chevy silv. I have the push button shift on the panel. I switch it in park and it blink for about 4 seconds then fine. So yeah the 4 seconds thing is normal im guessing. Like said about you can shift while moving (I read that in the user guide also) but I dont wanna risk it. I love my 99!