How to know if 2LO mod works.

I FINALLY installed the 2LO plug and play mod. I think it works..but I don’t know how to be sure.
I used the mod to inhibit 4WD and then selected 4LO (should give me 2LO). Everything felt ok, I guess, but I’ve never tried using 4WD on a dry surface so I don’t know what it would feel/sound like if the 4WD weren’t actually inhibited.
Is there any easy, fool-proof test I can run to make sure the mods actually works?

 

No experience with it. But if off the ground, guessing wheel speed should be different compared to 2 hi at a given rpm

 

You will know if it works. You will go like 25 mph at 4000 rpm.

 

Turn the wheel full crank and try to drive. If it drives normally and doesn’t immediately bind up then you are in 2LO.

 

Thanks y’all. To be clear, I’m not asking how to know if it’s in LO vs HI, I’m asking how to know if it’s in 4 vs 2.
Ok, so what I’m understanding is that I absolutely would have noticed it binding in 4WD? As in it’s not subtle at all? I just did a full crank turn and it felt fine.

 

Just to be clear, you can’t tell if your in 4 v 2?

 

Why is this a 2 LO module question?

 

Get all 4 wheels in the air and see if the fronts turn

 

Yes. The bind is obvious. The steering wheel will fight you and it will feel like the engine is loosing power.

Hell, give it a shot in a gentle turn, like a short distance on the outside of a cul de sac. You'll need to crank it back the other way to ease it back to 2Hi.

Most everyone will accidentally take a turn or two in 4Hi.

 

If it’s 2LO wouldn’t that mean the front differential isn’t engaged so turning the wheel won’t bind anything?

 

Yes. The 2LM engages the T case, but tricks the 4WD ECU into thinking that the ADD on the front axle is engaged. So, it is a great way to get in those 10mi of 4Hi on a curvy road. Of course, folks will want to cycle the system to keep the ADD actuator free and happy also.

 

Yes, and by not binding you know you are in 2LO and not 4LO like the switch says.

 

How about putting it in 2LO and jacking the ass end up? If the truck pulls itself off the jackstands by the front wheels you can be sure you’re still in 4LO, if only the rears spin while jacked up then you’re in 2.

 

That is one way to do it and is the way those goofballs demonstrated the SR5 TRAC functions on that YouTube vid, but that is a sketch method of testing.

Highly unlikely, but there is a risk of damage to the axle, or worse, hidden damage to the jack stands that folks really want to trust.

IMHO, the better jacking method for that would be getting all four wheels off the ground. Can be done with the same equipment, one jack and two stands.

 

At that point, jack up the front and rear and see what turns and what doesn’t

 

I can’t disagree at all with jacking the whole truck up off the ground, it would be much safer.
I should’ve suggested to only raise it just high enough to get the tires off the ground.

 

That's a lot of extra work when you can just turn the wheel and try to drive.

 

Agreed, but it doesn’t sound like the OP even knows what the feel of driving in 2Hi vs 4Hi is like.

 

It's all good.