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Newbie 4wd question

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Norcal Flyfisherman Enthusiast

Norcal Flyfisherman

Posted
Posted

Shifting into 4 wheel is not immediate, the wheels rotate while shifting takes place. I think it's only part of a tire rotation on these new trucks, but older trucks with automatic hubs could take several feet for 4 wheel to engage completely. I still prefer manual hubs for this reason, but they are hard to find these days.

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

Shifting into 4 wheel is not immediate, the wheels rotate while shifting takes place. I think it's only part of a tire rotation on these new trucks, but older trucks with automatic hubs could take several feet for 4 wheel to engage completely. I still prefer manual hubs for this reason, but they are hard to find these days.

GM never used auto hubs. They had an axle disconnect that was finicky at first but auto hubs and all the troubles that came with were a Ford thing.

scott19677 Senior Enthusiast

scott19677

Posted
Posted

Just something to look out for. For some reason GM thought it a good idea to place the headlight control knob and the 4X4 control knob very close together and the same shape. It would be a smart idea to ALWAYS check the setting of this when anyone else is driving your truck. The dummies at a full service car wash are very bad about moving the knob. Happened twice to me. Even the dealer has done it once. :driving:

The Fiddle Enthusiast

The Fiddle

Posted
Posted

2WD - Most all normal driving conditions.

 

Auto 4WD - Floor shift doesn't have this feature.

 

4HI - 4WD speeds up to 55-60 MPH MAX.

 

4LO - 4WD speeds up to 15 MPH. Think 4x4 trails in the mountains, or pulling out from boat launch, or pulling stumps, etc etc.

 

 

 

Floor shift > knob thingy.

redwngr Senior Enthusiast

redwngr

Posted
Posted

GM says you can shift into 4wd High at up to 75 mph and 4wd low should be operated at a maximum of 45 mph.

 

Shifting into or out of 4wd Low should occur with the transmission in neutral and the vehicle below 3 mph. (1-2 mph is optimum)

SouthernSilveradoGuy85 Senior Enthusiast

SouthernSilveradoGuy85

Posted
Posted

GM says you can shift into 4wd High at up to 75 mph and 4wd low should be operated at a maximum of 45 mph.

 

Shifting into or out of 4wd Low should occur with the transmission in neutral and the vehicle below 3 mph. (1-2 mph is optimum)

 

I've tried shifting in and out of 4lo and it still does it even with the trans in Drive. As long as you're going that 3 mph or slower (while still moving, not stopped) then it would be ok. My old truck you had to put it in Neutral, but this one you don't.

redwngr Senior Enthusiast

redwngr

Posted
Posted

It might work if speeds are correct, but the OM says it should be in neutral and (with the electronic and auto transfer case controls) specifically warns against shifting the transmission into gear before the transfer shift is complete.

JeremyW426 Enthusiast

JeremyW426

Posted
Posted

Manual Transfer case for the WIN! lol. ordered my 2015 WT blackout edition for this reason. The auto is nice and everything but there's too many electronic components that can fail. I'll stick with my direct linkage and floor mount 4WD and shift it myself when needed. :D

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

Hope they've gotten better. My 03 had a manual t case and it was junk. So fussy about engaging. Electronic shift on my 2011 never missed a beat. The Wrangler I have now is of course a manual t case and it seems ok.

MTB Enthusiast

MTB

Posted
Posted

Just something to look out for. For some reason GM thought it a good idea to place the headlight control knob and the 4X4 control knob very close together and the same shape. It would be a smart idea to ALWAYS check the setting of this when anyone else is driving your truck. The dummies at a full service car wash are very bad about moving the knob. Happened twice to me. Even the dealer has done it once. :driving:

Drove home from the detail shop a few months back in 4HI at 75mph...Transfer case was a little noisy after this for a day or so. But now it's all good.

MMC Enthusiast

MMC

Posted
Posted

GM never used auto hubs. They had an axle disconnect that was finicky at first but auto hubs and all the troubles that came with were a Ford thing.

GM used auto locking hubs in the 80's, I had them on my 82 Chevy and optioned out and got full manuals on my 87. They were slow to engage so I swapped them out with Warn premium manuals.

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