I got stuck in the snow the other day, and its making me wonder if my 4 wheel drive is working correctly. I hear the double click sound sound when I twist my dash **** to 4 high. I get the weird pulling from the front when I make sharp slow turns. However, if one of the rear tires loses traction (black ice up hill is a good example), then all the power seems to just go to the spinning tire, and I get no pulling power from the other tires. Is this correct? Isnt there something that should be telling the drive train that the wheel is just spinning and transfer some torque to the other wheels?

Help! This is the 2nd time its happened.
2003 5.4L fx4

 

any comments would be greatly appreciated.

 

Unless if you have a limited slip diff, in most cases, the wheel with the least resistance is going to spin. Usually it is the passenger side rear wheel that breaks loose first.

 

Look into a limited slip diff?

 

just a newbie here, pls bear with me.

so the stock 2003 fx4 does NOT have a limited slip diff?

 

Sounds like you need a limited slip. However my tru k is an 03 fx4 with factory 3.73LS. Check the axle code on the Vin sticker on the doorjam. If you do have a LS diff I would check the fluid level and maybe ad some additive to help the clutches out.

 

Two ways to check for limited slip, the first is the best.

1. Jack up rear axle so both rear tires clear gound, put tranny in neutral, spin one tire, the other will turn the same direction, if you spin one tire forward and the other turns backwards, its a straight differential

2. Not the preferred method, is to look at tag on axle for the letter L between the ratio. Example: 3L73 indicates limited slip. 3.73 indicates straight differential.

 

The axle codes on the VIN sticker on the drivers door jam I was reffering to are:
F-150:

19 – 3.55 Non-LS
18 – 3.08 Non-LS
H9 – 3.55 LS
B6 – 3.73 LS

 

I've got a B6 for my axle code. I guess I need to check my fluids. Any good links for a axle fluid tutorial? Should I try some sort of test to see if the limited slip diff is working correctly (I'll try Good Old Bill's test once I find a way to get the back end off the ground)?

and thanks a lot everyone! Your insights are most welcome!