How do I engage the 4x on an early 80's Chev Suburban K20, standard tranny and automatic locking front hubs

Question

I don't have a manual for this vehicle and not sure what the proper procedure is to engage the 4x. Do you have to stop the vehicle before shifting into 4x. Can u shift on the fly?

Answer 1

negative on the shift on the fly don even try it
in many cases the older vehicles required that you come to a complete stop prior to shifting the transfer case into 4wd hi or lo

actually, flip down the driver's side sun visor
i believe you will see the diagram the mfgr put there to explain this procedure

i will tell you that on these older vehicles you may experience extreme difficulty trying to shift out of 4wd
back up about 5-10 feet to release the pre-lad stress on the gears
this should allow you to ease back into 2wd
then, because you have auto-locking hubs you ned to back up 10 feet with wheels straight to unlock the hubs
now this is critical
if you put the truck into 4wd it will take a little forward motion for the hubs to engage
if you just put it in gear and gas on it hard you will "grenade" your hubs for sure
ease onto the gas and wait to feel the hubs lock in
then go for it
rule of thumb: if you coe to something you think u may need 4wd for, get into it before you drive into it
better to have it and not need it than to ned it and not have it
happy 4 wheeling

Answer 2

I have a '95 that has automatic hubs. All I have to do is shift into 4 high while driving. But then to shift into 4 low I have to put the truck into neutral while coasting at a slow speed (5 mph or less) and pop it into 4 low. Or else I can go to neutral on a crappy road and once my speedo hits 5mph or so while it decelerating I pop it into 4 low. So since you have automatic hubs I would assume that you have shift on the fly like mine. But if you want to be safe put it in 4 wheel while at a slow roll and in neutral/clutch pressed in. The slow roll helps everything engage all the way. And to take it out just pop it out at a slow roll with the clutch in. And it usually helps to back up a few feet after you go back to 2 wheel drive. It helps everything dissengage all the way, but it's not neccessary. Good Luck I hope you get it figured out. I would just try shifting while going slow if it goes in then you can shift on the fly. Just don't shift into 4 low while driving.

Answer 3

I am not sure about one that old but you should be able to shift the transfer case into 4X by slowing down to almost a stop and then shifting it into gear. This will get you to 4X High range. You might here some heavy clanking when the teeth are meshing together. To get to low range you my have to put the tranny in neutral and then shift to low....but I am not for sure.....

Good Luck

Answer 4

if it's manual hubs you have to lock them when the truck is stopped and the shift the truck into 4 wheel...NO shift on the fly...huge pain but if you have a problem much cheaper to fix