engaging 4 wheel HI: any speed?

simple · January 22, 2005

I have the electronic push button type on my 98 Silverado. When going from 2 wheel to 4 wheel HI or vise versa, can it be done at any speed? We all have heard that this can be done on the fly, but what does this exactly mean? Do people really engage this at 45 or 55 mph? I usually engage it at 5 mph or slower just to be safe. Any thoughts?

KG4LHQ · January 22, 2005

I have an 04 Silverado with the shifter at the bottom and I change it from 2WD to 4WD - 50 - 60 mph and it shifts with no problem at all. Unk if its the same for the push button

PeterbiltChrome · January 22, 2005

if all four wheels are going the same speed, it'll engage without one worry. You know that the fronts are Constant Velocity so the front axle is always turning (as opposed to the get-out-and-turn-da-hubs) I think if in case you need 4 wheel drive traction, there probably is a condition where you shouldn't need to be going more than 45-55mph... you're doing right with leaning on the cautious side, but it'll shift in at any speed when you command it~

I know there are thermo/electric couplers in there somewhere along the front drivetrain... I'm not too sure about that whole deal but there are plenty of other members who do~

mcreyaufmiller · January 22, 2005

In my opnion, I would only shift on the fly at the lower speeds, for example: below 40 mph. If I had to, I would shift at a higher speed, but prefer not to.

Shaners · January 22, 2005

You can do it at any speed. I would think the slower the better, but I guess it doesn't really matter.

I usually let off the gas a little when shifting in and out of 4wd on the fly...

MyBigToy · January 22, 2005

If I remember right, the owners manual says it can be engaged at speeds up to 60 mph. It will engage at speeds higher than that.

Rookie · January 23, 2005

I shift mine at any speed, but dont do it under power, or if the rear is already slipping. do it while coasting or driving on flat surface. If the roads turn to crap while im driving (like yesterday) i put it into auto track first then pop it into 4 hi. Just my .02

Roostman · January 23, 2005

Id say if your at speeds of 50+ MPH, then you more than likely have no need to be in 4wd. If you see the road gettin ugly, think ahead and put it in 4wd before you get into the bad stuff. My 2 cents.