A look at 4H (not 4A) operation

[R8er]

I mounted an old GoPro under the truck because I was curious to see how the 4H axles operated. Seems there’s a bit of misunderstanding out there. Here’s my 2021 5.0. Around 9:55 I turn on 4H to watch it operate. Then 10 seconds later I turn it off. Interesting to see it not disengage right away, maybe the EIWE waits to slow down first? It seems to disengage after I make a right hand turn and get back on the throttle.

Sponsored

 

[KingDavid]

In a 12:30 video, you didn't engage it until 9:53? Lol you gotta give us some time stamps. What time did you click it to activate 4hi?

Also, I wish it weren't snowing by you because I'd love for you to do a test hit; launch 4hi and click 2wd at the end of first gear to see if it disengages while still under WOT. And the same launch but disengaging while WOT in 2nd gear. I've heard mixed things and even I've had mixed results on my dragy, but video confirmation would be perfect.

 

[R8er]

I took that long because I wanted to make sure it wasn’t engaging at all unintentionally. I’m chasing a vibration as I decelerate/come to a stop.

 

[Radiganp]

Any chance you can do the same in 4a?

 

[HammaMan]

Any chance you can do the same in 4a?

Given the year of your truck, your front end is always live and your propellor shaft is always spinning. All 22+ TOD trucks have always-live front drivetrain. Only ESOF/Hi-Loc trucks can shutdown the front drivetrain (XL, XLT, Tremor, Raptor). 21 is the only year with EIWEs on TOD transfer case trucks.

 

[BurnsTremor81]

Given the year of your truck, your front end is always live and your propellor shaft is always spinning. All 22+ TOD trucks have always-live front drivetrain. Only ESOF/Hi-Loc trucks can shutdown the front drivetrain (XL, XLT, Tremor, Raptor). 21 is the only year with IEWIs on TOD transfer case trucks.

What is ESOF< and IEWIs?

 

[HammaMan]

transfer cases and devices that mechanically connect the front wheels to the half shafts

 

[BurnsTremor81]

No, what does the acronym stand for

 

[Radiganp]

So in 24’s the front is always live? Even in 2wd? I thought they still had the eiwe. Haven’t taken anything apart to find out.

 

[Radiganp]

No, what does the acronym stand for

Eiwe is electronic integrated wheel end I believe. The other I’m not sure of.

 

[HammaMan]

No, what does the acronym stand for

Doesn't matter, doesn't tell you its behavior. They're all technically ESOF.
ESOF on or off
TOD clutch
Hi Loc(k) = combined / both modes.

 

[BurnsTremor81]

well TOD is probably Torque on demand, so its splitting torque front to rear in the tcase i assume.

 

[HammaMan]

• 4A (Four-Wheel Auto): This is where the Raptor shines. It's an "on-demand" system that constantly monitors traction and automatically sends power to the front wheels as needed. This provides excellent stability and control in varying conditions like rain, snow, or light off-road trails. It's safe to use on any surface, including pavement. TOD + 4a Hi Lock
  
  
  
• 4H (Four-Wheel High): This is your traditional 4WD mode with a mechanically locked center differential. It's meant for more serious off-road situations where you need consistent power to all four wheels, like deep mud, sand, or rocky terrain. ESOF + Hi lock 4h

TOD is 4a clutch only. In 4h it just gets real stern w/ the clutch pressure but cannot lock up the t-case. All of GM's T-case are TODs. TOD can overheat and just go back into 2h

 

[powerboatr]

What was all that loose bolts noise.
Cool video
But that weird mechanical noise was unreal

 

[R8er]

So in 24’s the front is always live? Even in 2wd? I thought they still had the eiwe. Haven’t taken anything apart to find out.

It would be nice to have someone do a video of something other than a 2021.

Sponsored