FX4 Locking Differential
Lead Driver
Joined: Jul 2007
Posts: 7,868
Likes: 9
From: Rhode Island
Since you're mechanically linking both sides of the rear axle, as well as the front to the rear. Assuming that locking the axle gets the truck moving without any slip, then no, the front axle won't really be doing any pulling, as it is that one wheel on the rear axle pushing the truck along technically.
Mountain Pass
Joined: Jun 2006
Posts: 135
Likes: 0
That's what I'm thinking. 4x4 used to mean all 4 wheels having power, good or bad...slipping or not, and that's why the warnings about not using on a dry surfaces as they are all getting the same power all the time so if you turn, one of the front wheels is moving faster than the other...I think they called it "binding" because you could feel the truck trying to hop from grabbing. Now it sounds like the old 4x4 system without all this advance trac, roll stability sh#% was far better. Now I only have a 4x3 if I'm lucky due to the front end staying an open differential with the e-locker engaged only locking the rears together. I am getting really disappointed with this truck.
Mountain Pass
Joined: Jun 2006
Posts: 135
Likes: 0
Did it not lock the front and rear diffs so u had power pulling at all 4 wheels instead of this selective wheel that has traction crap. 2 me I could an allwheeldrive that would virtually out perform this system!
Lead Driver
Joined: Jul 2007
Posts: 7,868
Likes: 9
From: Rhode Island
No other factory 4 wheel drive trucks ever had locking front and rear differentials. Except the Chevy with the Eaton G80 Gov-Lok, but that was an option and they liked to explode, and that was only at the rear wheels.
4 Wheel Drive Systems since they first came out are virtually exactly as they are now. It is just the nature of how an open differential works.
4 Wheel Drive Systems since they first came out are virtually exactly as they are now. It is just the nature of how an open differential works.
Mountain Pass
Joined: Jun 2006
Posts: 135
Likes: 0
Okay. Guess I figured when I had an old Jeep Grand Cherokee get stuck in 4wd and was in a parking building turning the wheels I could feel the front "jumping/binding" and could hear the concrete squealing from the friction/traction where the fronts were turning at different speeds (thus each wheel had its own power) and that was just the front, so naturally I assumed if you engage a 4 wheel drive system (and by most manufacturers definition) it means all four wheels are being driven. From what I'm hearing here...I can leave it in 4 wheel drive and not worry at all about wear and tear because the differential is open and all wheels don't get the same amount of power all the time unless you engage the e-locker and it only locks the rears. Please educate me if I've just had this delusional idea about 4 wheel drive meaning "drive to 4 wheels" and not just meaning all the wheels "can" drive...it just depends on if its opposite wheel is slipping or not.
Mountain Pass
Joined: Jun 2006
Posts: 135
Likes: 0
I got this from "howstuffworks.com" and I know the F-150 is a part-time system. "The transfer case on a part-time four-wheel-drive system locks the front-axle driveshaft to the rear-axle driveshaft, so the wheels are forced to spin at the same speed. This requires that the tires slip when the car goes around a turn. Part-time systems like this should only be used in low -traction situations in which it is relatively easy for the tires to slip. On dry concrete, it is not easy for the tires to slip, so the four-wheel drive should be disengaged in order to avoid jerky turns and extra wear on the tires and drivetrain. " I'm still reading to re-educate myself but I recall when I had an Escape, it was really an all-wheel drive system (although Ford called it 4wd) and when we got a Sport Trac...I found it to be a part-time system. After researching I felt the part-time system was truly the better off-road/inclement weather vehicle.
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Mountain Pass
Joined: Jun 2006
Posts: 135
Likes: 0
Yeah, it's funny. I was watching a kid in an older F-150 on my way home with a lift kit and he was gunning it and had it sideways but pretty much in control on the highway. I was thinking if it just broke loose a little he would take a few folks with him but was intrigued watching the truck maintain a pretty accurate direction under more torque for conditions. Ah, to be young and stupid again. Anyway, I got into my subdivision and decided to try the 4x4 low so I stopped and put it in neutral...let it switch...backed up over the lip of my drive way and it started spinning. I was like, damn. Of course it is ice covered with about 2-3 inches of snow, but I was surprised. I think as was said before that the tires have a lot to do with the inability of this truck in certain conditions to shine. Wasn't crazy about the idea the thing came with 20's since I replaced 18's on my Lariat and that was more than a pocket full. But Tire Rack gave the Pirelli Scorpions a good rating in most variables but I'm not really seeing it.
Mountain Pass
Joined: Jun 2006
Posts: 135
Likes: 0
Oh, I forgot to mention...when I put it back in neutral and put it into 4 high it made the god awfullest grinding noise for some time. Had to let the brake off and roll a tad. Guess the teeth were just so that it wasn't meshing right.
Posting Guru
Joined: Nov 2009
Posts: 2,016
Likes: 3
From: NC
Shifting to/from 4L (4X4 Low)
1. Bring the vehicle to a speed of 3 mph (5 km/h) or less.
2. Place the transmission in N (Neutral).
3. Move the transfer case lever through N (Neutral) directly to the
desired position.
2. Place the transmission in N (Neutral).
3. Move the transfer case lever through N (Neutral) directly to the
desired position.
•
If the transfer case will not engage into 4L (4X4 Low) do not force
the lever. Allow the vehicle to coast at a speed below 3 mph
(5 km/h), then repeat Steps 2 and 3.
the lever. Allow the vehicle to coast at a speed below 3 mph
(5 km/h), then repeat Steps 2 and 3.
Note:
Some noise may be heard as the system shifts or engages; this is
normal.
normal.
Note:
For proper operation in 4X4 Low, ensure the transfer case shift
lever is moved entirely rearward in to the 4L (4X4 Low) position and
that the 4x4 Low light is displayed in the message center.
lever is moved entirely rearward in to the 4L (4X4 Low) position and
that the 4x4 Low light is displayed in the message center.
Note:
Ideal 4L (4X4 Low) shift conditions occur when the vehicle is
rolling at a speed below 3 mph (5 km/h) and the transmission is in N
rolling at a speed below 3 mph (5 km/h) and the transmission is in N
(Neutral).
Posting Guru
Joined: Jan 2008
Posts: 1,048
Likes: 1
From: altoona
i have the 18s with the goodyears and mine gets around like a tank in the snow no issue here
now my mom has a 07 with the 20s it get around in the snow but not the greatest
even tho the 18s come with better factory rubber i'd still like to get the 20s
now my mom has a 07 with the 20s it get around in the snow but not the greatest
even tho the 18s come with better factory rubber i'd still like to get the 20s