I posted this on another forum and got no response.

I noticed that when I start my truck, a "low range" light tests and goes off with all the rest of the dash lights. Well, I assume that is the 4Lo indicator. My 4Lo function works as far as I can tell since I can DEFINITELY feel a difference in the trucks demeanor when enguaged... but I get no light. Even in 4Lo, all I get is the "4x4" indicator.

Is there a potential problem I should be worried about?

 

check the manual and make sure that light is supposed to be for the 4lo setting...

if its not coming on and thats what its for, something is wrong somewhere, most likely electrical if the 4lo actually is working. you could get a wiring diagram and see what energizes that light when the 4lo is engaged, and start troubleshooting from there.

 

I haz no manual.

 

Download it.

https://www.fleet.ford.com/maintenan...ls/default.asp

 

The shift motor on the transfer case rotates to position 4L.
This signals the GEM modual to light the 4L lamp.
The contactor plate on this motor drive may need attention since the 4L lamp lights on inital check out.
This type faulure usually does not prevent the trans from going into 4L.
Good luck.

 

Thanks bluegrass.

I'm not really worried about it since it definitely works but I am experiencing quite a few little "oddities" with this truck that need to be sorted out. Thankfully this is nothing that REQUIRES attention.

 

make sure you have your truck in Nutral when you go from 4hi to 4Lo otherwise it will not go into 4lo... and sometimes you need to give it a minute.

 

That's not necessarily true. Last winter with all that freakin' snow we had here on the East Coast, I did a shift on the fly to 4H.... when I intended to turn it off on the fly, I had only switched it to 4L ( obviously I wasn't going fast). THEN... I had to stop the truck to get it out of granny

 

Hold the phone here!
Do not assume it's a "correct asumption" to be able to shift into 4L as you had experieced, unless there is a possible fault present.
Reason:
The GEM modual 'requires' three signals as 'holdoff' protection before entering 4L.
They are a brake pedal signal.
A TR. selector neutral position signal.
A no speed signal from the PCM.
Reference user manuel pages 181-182.
.
Primary reasons are the huge difference in gear reduction that takes place may cause accident or injury to passengers, inside loose articles shifting, damage to transmission/drive train, loss of vehichle control and a large change in the shift program.
Example; think of what it would it be like is this could happen at 50 mph on pavment, gravel or slick road surfaces ; each could result in a different outcome.
Do not think for a minute that FMOCO would want libility problems from such results and therefore has built in the protections against 4L engagement.
Not to mention insurance companies libilities from such results would not stand for ''no protection' being built in.
Even cruise control has several ways to disengage as protection the motor does not add a runaway condition or add to panic braking reaction causing accident.
The torque convertor even unlocks at brake application to 'reduce' some of the motor's forward drive at the same time panic braking is needed.
You are free to disagree but these are the facts.

 

Yeah... I would never shift into 4Lo when moving, even if it won't enguage until stopped. I remember I accidentally did that in a Jeep Grand Cherokee I had back in High school and it just about sounded like it was gonna blow up! Haha. Irony is that it did in fact blow up. Not then, but about 10 months later. Tranny failed (third time in 120k miles) and #3 cylinder blew a water jacket within two weeks. Carmax took it off my hands for $4700 with 120k miles and no a/c or CEL bulb... HAHAHAH.

 

Right, just because the switch points at 4L doesn't necessarily mean the truck is in 4L. And if you were able to shift into 4L while moving and in gear, somethin's broke.

 

Since I have had the truck, I have never 'intentionally' put it in 4lo.... let alone doing it while moving from a higher gear. But it did happen....once. And at the time,my foot probably WAS on the brake... going at a slow speed as stated. That said, it still leaves to wonder why it did it at all if not in P or N. I do not intend on trying to replicate the scene of the crime.... but will keep this in mind for future 4wd uses.

As always though, I appreciate Bluegrass sharing your knowledge of the deeper details some of us yet do not know ..

 

In my case... it definitely was. When you're in granny, you just ain't goin' nowhere fast. When it happened, I was like..... WTF?!

 

It's not a bad idea to switch into 4hi and 4lo every once in a while.

 

Agreed. And since I haven't done that since last winter, I suppose it is due.