I recently got the truck and have been experimenting with it. I put the truck into 4low to go up a steep hill and found that 4low doesnt make a gear reduction like a older style tcase but rather gives it now power. I have also found when I turn overdrive off the power is also reduced. I have never encountered it before, is that normal? Would a tuner or chip change this?

 

You recently got what truck? We can't see what it is through the Internet.........

 

Sorry, its a 2004 F150 STX 4X4 4.6l

 

4wd **** or lever?

 

4 low is for pulling tree stumps out of the ground! LOL You can only go about 5-10 MPH in 4 low! Only move the lever into 4 low when stopped.

 

no!

 

http://www.fordservicecontent.com/Fo.../04f12og4e.pdf
Go to page 162 in this manual

 

Not true. In overdrive it would top out around 70 mph. Even in 1st gear it will do 20.

 

I said, You can only go about 5-10 MPH in 4 low! Using a manual 4WD system (if equipped)
2H (2WD High)
–
Power to the rear wheels only; used for street and
highway driving. Provides optimal smoothness and fuel economy at high
speeds.
4H (4WD High)
–
Used for extra traction such as in snow or icy roads
or in off-road situations. Not intended for use on dry pavement.
N (Neutral)
–
No power to either front or rear wheels.
4L (4WD Low)
–
Uses extra gearing to provide maximum power to all
four wheels at reduced speeds. Intended only for off-road applications
such as deep sand, steep grades or pulling heavy objects. 4L (4WD Low)
will not engage while the vehicle is moving; this is normal and should be
no reason for concern. Refer to
Shifting to/from 4L (4WD Low)
for
proper operation.
Shifting between 2H (2WD high) and 4H (4WD high)
•
Move the transfer case lever between 2H (2WD High) and 4H (4WD
High) at a stop or any forward speed up to 55 mph (88 km/h).
Note:
Do not perform this operation at speeds above 45 mph (72 km/h)
if the outside temperature is below 32
°
F(0
°
C).
Note:
Do not perform this operation if the rear wheels are slipping.
Note:
Some noise may be heard as the system shifts or engages; this is
normal.
Shifting to/from 4L (4WD Low)
1. Bring the vehicle to a complete stop.
2. Depress the brake.
3. On vehicles equipped with an automatic transmission, place the
transmission in N (Neutral); on vehicles equipped with a manual
transmission, depress the clutch. It think NOT! May be in 4H not 4Low

 

RAM23 I have the same truck as you do, just turned 210,000 miles an it. Still running strong. I have an Edge tuner that helps with changing the shift on the trans so it shifts into high gear fast, which saves me on gas.GLC has a 2 wheel drive, we are talking about 4 wheel drive in 4-low,not 2wd truck in low!

 

I'll say this again. I AM talking about a 4wd truck, what on earth makes you think I'm talking about MY truck? I'll redo my math using actual numbers, assuming a 3.55 axle ratio and 32" tires.

http://4lo.com/calc/gearratio.php

I used:

Tires - 32
Diff - 3.55
RPM - 5000
Trans - 2.84 in 1st, 1 in 3rd, 0.7 in OD
TC ratio - 2.64

1st: 17.9 mph
3rd: 50.8
OD - 72.6

If the tires and/or axle are different, the numbers will be different, but not by a whole heck of a lot.

 

I understand about shifting into 4low with the brake depressed and in neutral. That exactly what I do. My question was once im in 4 low I have no power. You said 4 low is for pulling out tree stumps. I cant even climb a hill. I have to press the throttle 1/2 before my truck moves and full throttle I am barely moving with no torque. I know you shouldnt be going very fast but I have zero power like it is computer regulated, if i hit a mudhole I feel like I would stop moving and torque out. Is that normal? I know my old mazdca truck in 4 low I have tons of power compared to 4 high but the ford has way more power in 4 high. Also I have 215,000km and I have lost overdrive gear.

 

Its not normal at all! You may be having a problem inside the transfer case its self, with something binding up. Can't use Mercon V fluid in it or it will blow the transfer. May be someone put the wrong fluid in it??? If 4 High works OK , then transfer needs to be looked at. OD not working could be anything. I don't think the two are connected. I would take it to a trans guy and have him test drive it.

 

What????? Mercon was the original specification, but is no longer available, Ford has approved Mercon V for all applications that used to specify Mercon.

The 04 has an electronic throttle - I suspect you have an electronic issue, not a mechanical issue. Have you checked the OBD2 for codes?

 

I am a level one mechanic and have access to scan tools and other educated technicians. My OD band is broken or a actuator is gone. I know its not a related issue. The tcase issue doesnt feel like its binding up because it works flawlessly. It just feels like the lower gears have a govener so you cant damage the driveline or something. When I turn my overdrive off the 1-3 gears feel like they are goverened not to have full power along with moving my shifter into the 1 and 2 position it feels like my power is governed. For example if I was in drive and OD on i could spin my tires on gravel with no problem but if i put it into 1rst position my rear tires wouldnt break loose. It does give me hold back going down hills though. Older trucks when u put the shifter into a lower gear you have a lower gear ratio and more power but it seems like it gears down and then the computer governs the power so you dont damage the rest of the driveline.