1984 f-150 front diff is leaking - 1984 Ford F 150

remove the rear cover all the bolts except the top 1 just loosen that 1. Put a bucket under the rear diff and open the diff cover and drain out the fluid. clean and reseal the diff. remove the plug on the front of the diff and fill with the correct diff fluid until it is filled up to the hole and replace the plug, clean up and check for leaks. No leake = job is complete.

needs a saver sleeve on the yoke..or a new yoke

If the seal is leaking, it will need to be replaced, if you have a service manual, it will show you the procedure to replace the seal. DO NOT try to replace the seal without following the proper guidelines as input bearing damage can occur. After the repairs are made, be sure to to clean the vent tube/valve on the diff. to avoid pressure build up that will cause early seal failure, this vent should also be cleaned at every oil change.

You have to pull the drive axles out to
change diff seals

if the leak is from the rear portion of the diff, often it can be cured by removing the cover, cleaning the mating surfaces, resealing and reinstalling. if the cover seems to have excessive corrosion inside, replace it. they are relatively inexpensive and available at almost any parts store, but original dodge ones from the dealer fit the best.

if the leak is from the front portion of the diff (front seal), this requires a some work beyond the scope of most home mechanics, but is not usually a very expensive job. good luck!

mcdevito75, The tranny has a front pump to pump fluid back and forth to the torque converter, a seal must be leaking fluid into the diff. also the diff, has tranny fluid in front wheel drive cars so tranny fluid in the diff. is normal, Tranny will have to come out to check that front pump, or fron tranny seal.

If the front differential is covered with oil, chances are that the leak is from the pinion seal on the diff itself or from an engine leak. check all the fluids and find what is low and clean off all the residue there so you can find the source. Since the t case is behind the diff, and the air flow is towards the rear (unless you drive backwards all day long) any leaks would tend to blow towards the back, not towards the front.Once you find the actual leak source, someone here can help advise you on how the repair can be made.

You did not specify what year it is. You need to know what controls the front diff-lock, is it vacuum or electronic? If it is vacuum then you need to inspect the system for vacuum leaks and/or faulty vacuum devices (switch on transfer case, diaphragm on front diff, etc). If it is electronic you need to have it checked for codes, and/or service the differential controls found in the front diff casting.

remove entire trans,remove 8 bolts and then remove front differential case at this time you will need to remove torque convertor with tube do not remove this tube from the convertor it drive the oil pump, the gasket is liquid gasket make sure surface is clean,also at this time replace torque convertor seal and seal tube this tube seperates transmission fluid from gear oil good luck

The front diff in this model requires air pressure to engage. There is an electric pump for this purpose and once the pressure rises and remains where it's meant to, the pump shuts off and the dash light indicating 4WD will remain lit. It is sealed. There should be no leaks. If there is air coming out the top, do you mean out of the diff breather pipe? (The diff breather should be connected to a hose that goes up and is clipped next to the radiator.) If it is coming out of the diff breather, you have a punctured (worn out) diff engaging diaphragm which can only be replaced by stripping the diff casing.