2001 chevy 4x4

1968427rsss · 01-02-2009, 09:37 PM

2001 chevy1500 4x4 front drive shaft turns all the time its in two wheel drive help.

**Raylo** · 01-03-2009, 06:29 AM

This is normal for 4x4 vehicles with automatic "hubs". The actual engagement takes place in the transfer case hence the shafts always turn, even when they are not engaged and powered.

pickerbush18 · 01-03-2009, 05:45 PM

I don't think this is normal because you will create wear on the front axle parts. I have a Dodge truck with auto locking hubs. When you shift out of 4x4 mode the front axles disengage which in turn stops the front axle from rotating.

**SABL** · 01-04-2009, 01:00 PM

If 1968427rsss has auto hubs, I would say he has a problem with the hubs not disengaging. The hubs should be disassembled and inspected for damage or lack of lubrication.

If the hubs are manual the problem is obvious.... the owner has to disengage the hubs by turning the locking control at the hub.... on both sides.

http://www.aa1car.com/library/2004/bf60414.htm

**Raylo** · 01-05-2009, 05:30 PM

Here is a good writeup of how a modern 4x4 with auto "hubs" works. It's for a Dodge Ram but should be similar to a Chevy. Note that the disengagement happens near the transfer case and that since the half shafts are connected to the wheels they are always tuning if the wheels are turning. There is no disengagement on the wheel side of the CV joints so unless you take the CV joints out, the shafts are gonna turn. My Chevy trucks have always worked like this and they were not broken.

http://dodgeram.org/tech/repair/4X4/4x4_engagment.htm

**SABL** · 01-06-2009, 08:55 AM

Hi Raylo

Great link!!

Quote:

When I am operating my Suburban on the street with 4WD disengaged, my
> front axles do not turn. However, I notice that on the Dodge trucks, on the
> street, the axles are turning. So what is happening here?

In 94 and newer Dodge trucks, the front axles always turn. There are no hubs at the front wheels to engage/disengage. Inside the front axle housing, on the passenger side, the front axle is split. There is a spline coupling that slides back and forth to connect/disconnect the front axle. This spline is controlled through the transfer case shift lever.

It seems Chrysler cut costs by eliminating the locking hubs on some 4WD's. Mopar saved the $$ but it costs the owner in gas due to having to "drag" the front drivetrain. The front differential is always turning, along with the transfer case.... the only thing missing is the link-up to supply power to the front-end. The only thing I can think of that is good in this scenario is that all the components (including the seals) are in motion and being lubricated at all times. But, as far as I am concerned, with this set-up you might as well be running a full-time 4WD.

Thanks for the link....it got me thinking about my Cherokee 4WD. After taking a peek at it, it seems I have the same typical Chrysler set-up. I will be replacing the outer U-Joints soon and might look into some after-market hubs if they are available.

SABL

**Raylo** · 01-06-2009, 04:00 PM

Thanks, SABL. That was a good writeup indeed.

I went through a similar episode myself when I did the first brake job on my recently traded 1994 S-10 4x4 pickup. I jacked it up and spun the drivers side wheel only to see that halfshaft turned! I had an OMG reaction then took a closer look. Turns out most of these vehicles with electronic part time 4x4 don't have operable hubs. There was a little encoder motor on the t-case that put it in the correct mode (2hi, 4hi, 4lo), and there was a vacuum actuator that engaged the front axles to the front diff. The halfshafts were directly connected to the hubs forever to turn.

I just recently traded the S-10 on a 2009 Toyota Tacoma 4x4 and I suspect it works similarly but I haven't had the need to tear into it... and hope I won't have to for many years. :-)

01-02-2009, 09:37 PM	#1 (permalink)
1968427rsss Registered User Join Date: Jan 2009 Posts: 1 OS: xp	2001 chevy 4x4 2001 chevy1500 4x4 front drive shaft turns all the time its in two wheel drive help.

01-03-2009, 06:29 AM	#2 (permalink)
Raylo TSF Enthusiast Join Date: Feb 2006 Location: Maryland, USA Posts: 525 OS: XP Desktop, Vista HP Notebook, XP Notebook	Re: 2001 chevy 4x4 This is normal for 4x4 vehicles with automatic "hubs". The actual engagement takes place in the transfer case hence the shafts always turn, even when they are not engaged and powered.

01-03-2009, 05:45 PM	#3 (permalink)
pickerbush18 Registered User Join Date: Jan 2009 Posts: 4 OS: vista sp1	Re: 2001 chevy 4x4 I don't think this is normal because you will create wear on the front axle parts. I have a Dodge truck with auto locking hubs. When you shift out of 4x4 mode the front axles disengage which in turn stops the front axle from rotating.

01-04-2009, 01:00 PM	#4 (permalink)
SABL Moderator Relaxation Room Join Date: Jul 2008 Location: Galena, Ohio Posts: 1,203 OS: WinXP SP3	Re: 2001 chevy 4x4 If 1968427rsss has auto hubs, I would say he has a problem with the hubs not disengaging. The hubs should be disassembled and inspected for damage or lack of lubrication. If the hubs are manual the problem is obvious.... the owner has to disengage the hubs by turning the locking control at the hub.... on both sides. http://www.aa1car.com/library/2004/bf60414.htm

01-05-2009, 05:30 PM	#5 (permalink)
Raylo TSF Enthusiast Join Date: Feb 2006 Location: Maryland, USA Posts: 525 OS: XP Desktop, Vista HP Notebook, XP Notebook	Re: 2001 chevy 4x4 Here is a good writeup of how a modern 4x4 with auto "hubs" works. It's for a Dodge Ram but should be similar to a Chevy. Note that the disengagement happens near the transfer case and that since the half shafts are connected to the wheels they are always tuning if the wheels are turning. There is no disengagement on the wheel side of the CV joints so unless you take the CV joints out, the shafts are gonna turn. My Chevy trucks have always worked like this and they were not broken. http://dodgeram.org/tech/repair/4X4/4x4_engagment.htm

01-06-2009, 04:00 PM	#7 (permalink)
Raylo TSF Enthusiast Join Date: Feb 2006 Location: Maryland, USA Posts: 525 OS: XP Desktop, Vista HP Notebook, XP Notebook	Re: 2001 chevy 4x4 Thanks, SABL. That was a good writeup indeed. I went through a similar episode myself when I did the first brake job on my recently traded 1994 S-10 4x4 pickup. I jacked it up and spun the drivers side wheel only to see that halfshaft turned! I had an OMG reaction then took a closer look. Turns out most of these vehicles with electronic part time 4x4 don't have operable hubs. There was a little encoder motor on the t-case that put it in the correct mode (2hi, 4hi, 4lo), and there was a vacuum actuator that engaged the front axles to the front diff. The halfshafts were directly connected to the hubs forever to turn. I just recently traded the S-10 on a 2009 Toyota Tacoma 4x4 and I suspect it works similarly but I haven't had the need to tear into it... and hope I won't have to for many years. :-) Last edited by Raylo; 01-06-2009 at 04:01 PM.