I got differential fluid coming out breathing line on my front dif wen driving in 4 wheel drive at 90km

check the front drive shaft spline or "U" joint at the transfer case
splines on this shaft wear more quickly that the rear drive line
as the operation angles for the front diff are more acute that the rear shaft

The actuator will not be on the front differential or drive line, it will be on the transfer case, which is mounted behind the transmission. Follow the front drive shaft back from the front differential, and the component at the rear of the driveshaft is the transfer case. That is where four wheel drive is engaged/disengaged.
I'm not familiar with your vehicle, but if you have a separate lever to engage 4wd, there will not be a fuse for the actuator - it is a manual system. If the 4wd is selected electrically, check that all wiring and connectors on the transfer case are in good condition.

What kind of car or truck? If both driveshafts turn, then you have a bad front differential. Remember there are 2 driveshafts on 4 wheel drive vehicles. Also do you ahve locking hubs?

Elaine,

not work, do tell what makes you think it dont work (a lamp) or tires slipping or dead tires. (by tires mean that and traction)??????????

what mode fails, of the many, and where.???????



first off, we dont know what your tires are touching.

on road, or off road. pavement or ICE or snow.

that matters big time . (you read manual and match MODE to Road)

your lost operators guide explains all that, right?

eg: how and when to use, 4wd, its all there. I promise.

ControlTrac 4-wheel-drive system



here are the mode. which one , gives you problems.



quote ford with comments.



What are the modes, and how do they differ?

(note this is the operational behavior of a 2008 Ford Expedition. Newer and older Expeditions will vary only slightly)



• 2H 2-wheel-drive with high range gearing (1.00:1) Rear-wheel-drive capability,

2-wheel electronic traction control system is enabled



• 4A 4-wheel-drive Auto with high range gearing (1.00:1) Full-time all-wheel-drive capability, ((best on pavement or any time)

Electronically adjusted torque split to front & rear wheels, Electronically variable center differential,

Front driveshaft & rear primary driveshaft allowed rotational speed difference,

4-wheel electronic traction control system is enabled



• 4H 4-wheel-drive with high range gearing (1.00:1) Part-time 4-wheel-drive capability, (not for dry pavement EVER)

Continuous 50/50 torque split to front & rear wheels, Electronically locked center differential,

Front driveshaft & rear primary driveshaft mechanically locked with no rotational speed difference,

4-wheel electronic traction control system is enabled



• 4L 4-wheel-drive with low range gearing (2.64:1) Part-time 4-wheel-drive capability, (off road usage, mostly)

Continuous 50/50 torque split to front & rear wheels, Electronically locked center differential,

Front driveshaft & rear primary driveshaft mechanically locked with no rotational speed difference,

4-wheel electronic traction control system is enabled, ESC and RSC are disabled



In 4A mode the center differential is electronically-controlled and rear drive wheel bias. The on-board computer monitors for any sign of rear drive wheel slip (loss of traction)

If loss of traction is detected, the center differential is told to send a share of the engine\'s torque to the front drive wheels. It will not let the front driveshaft turn at the same speed as the rear driveshaft.



What about traction management?

1997-2002 model Ford Expeditions offered an optional limited-slip rear differential (LSD). A conventional open rear differential was standard along with the conventional open front differential and the electronic locking center differential.

comment with out LSD, one tire can spin, on say ice.

but the other 3 tires dont, in full time.

First I think you read it wrong ,that Front WD suv have locking dif..they don't , it locks at the transfer case at the tranny and only on All Wheel Drive SUVs. And then it only transfer more power from back wheels to front wheel. The dif are open dif. means the power goes to the wheels with least resistance or limited slip dif. that transfers power to slower turning wheel. Yes max. load is at full lock and high speeds and yes it does damage over time (wear out), less at lower speeds. The symptoms of a failing cv is knocking while turning.

Hi, there, Check your break pads. Could be from there.
cheers

What does it mean when the Service 4 wheel drive light come on?

WELL WHAT YERA IS THIS TRUCK AND IS THE SOUND COMING FROM FRONT OR IS COMING DOWN DRIVE LINE IT COULD BE AT TRANSFER CASE THAT WHY IT GOSE AWAY WHEN IN FOUR WHEEL YOU COULD PULL THE DRIVE LINE IN FRONT AND SEE IF NOIS GOSE AWAY THEN ITS IN FRONT IF ITS THERE WITH DRIVE LINE OUT PUT IN GEAR AND IF NOIS GOSE AWAY THEN ITS THE TRANSFER CASE

Has this Jeep been modified at all?
It sounds like the shifter cable was reinstalled backwards.
Specifically the 4-Low "Not Climbing Well". 4-Low should give you the best torque and hill climbing ability.
Do you feel any "Binding" in the steering wheel (difficult to turn)?
Remember a Jeep uses real driveshafts and differentials to give you 4WD - you cannot engage 4WD or 4-Low on dry hard surfaces. It needs a little bit of slip between the wheels for turns.
Check you're fluids too.

91-97 Land Cruisers had a factory option for front and rear locking differentials. This is a seperate switch and is usually located to the left of US model Land Cruisers. The center dash button locks your transfer case differential changing your Land Cruiser from all wheel drive to four wheel drive depending if you have ABS or not this button either says ECT or Center Dif Lock. If you do not have the Front/Rear locking differential option then your Land Cruiser has open Front and Rear. Hope this answers your question.