When can I engage cdl? (1 Viewer)

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My bro and I are trying to figure this out. Recently installed cdl switch... when can we engage the button? We know under what conditions to press it (gravel, wet, etc) just what is the manner in which you engage it?

I’m under the impression you can engage it sitting still or while driving in a straight line at a reasonable speed, maybe less than 35 mph. My bro thinks it’s just when sitting still with no movement.

What’s the verdict? Can’t really find anything Through search and just don’t want to mess anything up.
 
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You can engage/disengage it on the fly as needed. I'll click mine on before I hit deep snow when on gravel roads. I've never needed it on paved roads, even if they are snow covered.
 
If you're actually wheeling your truck, you would benefit from doing the 7 Pin Mod, which is described on Slee's website and in numerous posts on this board. The benefit of the 7 Pin Mod is that you can turn off the center diff lock and still be in 4 Low, which is nice in tight turns to prevent binding the drive train.
I wheeled my truck for a few years before I bothered doing the 7 Pin Mod, and I wish I had done it sooner. It's a great mod and is totally free. You just cut (or remove) one small wire in the driver's side left kick panel. You can also easily reverse the mod if you don't like it.
Happy trails!
 
Front and rear lockers can be activated at 5 MPH indicated speed or less and can stay locked above that speed but be aware that they can adversely affect steering control and can be very dangerous and unpredictable in off-camber situations. The rule of thumb is when using them is to turn them off as soon as traction is no longer an issue. They are not for higher speeds. Those concerns are not applicable to the CDL.
 
"you would benefit from doing the 7 Pin Mod"
It's called the PIN 7 MOD

"The benefit of the 7 Pin Mod"
It's called the PIN 7 MOD because you're modifying PIN 7.

"before I bothered doing the 7 Pin Mod,"
It's called the PIN 7 MOD because you're NOT modifying 7 pins
 
I'm glad the internet has provided an outlet for people who can't think of a clever thing to say in the moment. Those people matter, too.
 
that said, you don't need to do the pin-7 mod if you just instead pull the wiring plug off the transfer case switch - pulling the plug off will disable feedback from the transfer case to the ECU, so the ECU won't know you put the transfer case shifter into low range manually, and instead will continue to shift gears in the high-range pattern, and also will keep the ABS on (as it is normal to be engaged in high range) - unless you push the CDL button and lock the center diff, which also also disables ABS breaking (bad to have on dirt, been-there-done-that) - since the ECU does not engage the low range gear shift pattern without the feedback from the transfer case whether it is indeed in low range (as the plug is off), you would then have to shift the truck manually into lower gears on the trail

granted, that's all quite nerdy, but I happen to be a scientist :hillbilly:
 
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