4x4 Question

[Shantheman73]

So...it was snowing in KC last week...so I put the Expy in 4WD high a few times when the roads were really slick. This thing is a beast in the snow!
Tonite however, I noticed my steering feels heavy...as though the 4WD is engaged still...even when I have it in 2WD. Is it possible it's still in 4WD without the dash indicating as such? I put it in 4WD while driving at a low speed and then put it back to 2WD hoping that it might help...but it still has the same heavy steering I feel when 4WD is engaged.

 

[Fastcar]

Try slowly backing up with it in 2wd, turn the steering wheel slowly back and forth while moving in reverse

 

[Shantheman73]

I’ll try that and let you know. Thanks!

 

[ExplorerTom]

Try turning in tight circles in an empty area. Does it turn smoothly or does it feel like the driveline is binding up?

Also, check your tire pressure.

 

[Shantheman73]

Try turning in tight circles in an empty area. Does it turn smoothly or does it feel like the driveline is binding up?

Also, check your tire pressure.

Yeah…first thing I checked was tire pressure.
Negative on the binding up. It still turns smoothly.

 

[JExpedition07]

Yeah…first thing I checked was tire pressure.
Negative on the binding up. It still turns smoothly.

If it was in 4WD it would be banging and clunking loudly in a tight turn

 

[Shantheman73]

If it was in 4WD it would be banging and clunking loudly in a tight turn

Ok that’s good info.
I drove it to work this morning and noticed two things:
1. It’s not consistent
2. When it’s happening, the steering wheel doesn’t want to come back to center after turning a corner.
Would that be power steering related? It’s not making any odd sounds, just suddenly gets heavy at times.

 

[Timo2824]

The hubs are disconnected using engine vacuum. Sometimes a vacuum leak in the system can cause the hubs to always be engaged. Also a solenoid that controls the vacuum being sent to the hub can fail. I've had hubs get frozen engaged after driving through a bunch of snow as well. When you turn on 4x4 auto the hubs are locked, so driving around with them locked is okay as long as the transfer case is going to 2wd or auto 4x4.

 

[Shantheman73]

The hubs are disconnected using engine vacuum. Sometimes a vacuum leak in the system can cause the hubs to always be engaged. Also a solenoid that controls the vacuum being sent to the hub can fail. I've had hubs get frozen engaged after driving through a bunch of snow as well. When you turn on 4x4 auto the hubs are locked, so driving around with them locked is okay as long as the transfer case is going to 2wd or auto 4x4.

Ok…that makes sense.
Today I jacked up the front end and pulled tire off. If the hub is still engaged…does that mean the half shaft spins with the wheel? Or does it spin with the wheel even when the hub isn’t engaged?
Sorry for these questions: I’m not familiar with how the 4WD works on this thing.

 

[Shantheman73]

Ok...I jacked it up again with the engine running (to create vacuum) and the driver wheel spun freely...the passenger hub was engaged.
Now........I'm betting it's probably the seal at the wheel hub that's leaking?

 

[ExplorerTom]

Or somewhere in the line going to that wheel. Ah the joys of old brittle vacuum components……

I just installed hub lockouts this weekend on mine. Now my front axles are always engaged but 4wd is still determined by the transfercase. No more grinding, no more noise, no more vacuum system components to worry about.

 

[Shantheman73]

Or somewhere in the line going to that wheel. Ah the joys of old brittle vacuum components……

I just installed hub lockouts this weekend on mine. Now my front axles are always engaged but 4wd is still determined by the transfercase. No more grinding, no more noise, no more vacuum system components to worry about.

What are lockouts and how are they different than just leaving it in 4WD auto all the time? Doesn’t that just leave them engaged too?

 

[justinp16ex]

What are lockouts and how are they different than just leaving it in 4WD auto all the time? Doesn’t that just leave them engaged too?

Yes, 4 Auto leaves them engaged all the time, but the transfer case will put power to the front drive line. With the lockouts there is no power going to the front unless 4A or 4WD is selected. The hubs are always engaged, but no more need to worry about vacuum line failure or IWE failure. The reason they use the IWE system is to eliminate the small MPG losses you may have from having the front hubs locked in all the time. The losses or gains are likely not noticable.

 

[Shantheman73]

Yes, 4 Auto leaves them engaged all the time, but the transfer case will put power to the front drive line. With the lockouts there is no power going to the front unless 4A or 4WD is selected. The hubs are always engaged, but no more need to worry about vacuum line failure or IWE failure. The reason they use the IWE system is to eliminate the small MPG losses you may have from having the front hubs locked in all the time. The losses or gains are likely not noticable.

So for now…I’m fine to drive around in 4WD auto? The only thing I notice is how the steering feels much different.

 

[justinp16ex]

So for now…I’m fine to drive around in 4WD auto? The only thing I notice is how the steering feels much different.

The only time I had the heavy steering wheel feel was when I got into the throttle while Auto 4 was engaging, I got a clunking noise and the steering wheel was heavy to the left. After I drove a few feet without Auto 4 engaged, the steering corrected itself. I would check to see that both hubs are engaging when you go to 4wd instead of just one.

 

[mjp2]

What are lockouts and how are they different than just leaving it in 4WD auto all the time? Doesn’t that just leave them engaged too?

Part # and price reference: https://www.amazon.com/dp/B07DWDYTB9/

 

[Fastcar]

WTF don't they bring back the manual locking hub? I guess people just became too lazy to turn a red disc.

 

[Shantheman73]

The only time I had the heavy steering wheel feel was when I got into the throttle while Auto 4 was engaging, I got a clunking noise and the steering wheel was heavy to the left. After I drove a few feet without Auto 4 engaged, the steering corrected itself. I would check to see that both hubs are engaging when you go to 4wd instead of just one.

OK, that helps. I think the weird thing for me is that while I’m driving around in 4WD auto, sometimes the steering wheel is heavy in corners, and sometimes it’s not. I’m not sure what issue that points to, because technically the hubs are engaged. Maybe the transfer case is actually sending power to them when that’s happening?