Question about 2004 Ford F150

1 Answer

2000 Ford F150 rear differential fluid VANISHING

Ok. I have a ford F150. A few months ago i noticed there was a slow leak/drip on my rear differential. After poking around i realized it was not the actual pan that was dripping, but the Pinion seal had gone bad. So me and a buddy changed it. Now over any amount of short distance (basically 55mph and over) drive it runs out. I see no sign of leaking anywhere, its like the fluid just vanishes. Itll be full of gear oil- i go 30miles- and its shuttering again DRY

Posted by on


1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Ford Master
  • 5,687 Answers

This is different. In a perfect world, you would run the truck on a dynamometer, get it up to 55 MPH and look under the truck. The fluid is going somewhere.
There is a vent tube on most axles. Follow the tube to find its' end and see if the fluid is traveling away from where you had expected a leak. Check your axle shafts under the rear rotors to see if the Emergency brake drum is oil coated.
Another way to think about this is the original failure. The pinion seal. The seal contacts the rotating flange. If you have a wobble in the driveshaft, (balance issues, U-joints) then the rotating flange can wobble. If you have a bad pinion bearing or carrier bearing, it can work to make the spline gear wobble.
So I am suggesting that the leaking Pinion seal was caused by something and the seal was a casualty of an undetermined cause.
You should be able to add an Ultra-violet dye to the axle fluid to find your leak. Even if it is running from the same place, the current leak will be showing the UV dye.
Please rate my info.

Posted on May 05, 2013


5 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017

  • 324 Answers

SOURCE: Ford escort 97 model vtec 1.4 l.oil leak clutch seal outer

it sounds like your valve cover is bent, you may need to buy a new one, did you use any gasket sealer with the cork gsket? if not remove the valve cover and use gasket sealer..... Apply it driectly to the cork gasket...... if you did not use sealeant this is why it is leaking.

Posted on Nov 26, 2008

  • 299 Answers

SOURCE: In Aug 05, at 75K miles, my 2000 EB Ford Exp took

no they are not suposed to leak period if it is leaking there is some defect

Posted on Sep 23, 2009

  • 80531 Answers

SOURCE: 2000 ford focus oil leak

Sounds like the valve cover gasket, clean off all the oil on the engine with a pressure washer or a steam cleaner and then drive it and recheck for the leak, that way you can pin it down for sure.

Posted on Oct 19, 2009

  • 43 Answers

SOURCE: how can i change the rear main oil seal on a 80

I would suggest you buy a Chiltons or Haynes repair manual for your truck. They run $15 to $20. This is a pretty tough do it yourself project. They will give a lot of good guidance, photos, and tips. It also depends on which motor you have. It will probably be a couple of pages worth of instructions.

Posted on Feb 14, 2010

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

My transmission gage went to hot & i noticed trans fluid dripping on my way home. truck still shifts ok. 2002 ford f-250 diesel 4x4

The most common place to leak is the rear seal. You will have to put your eyes on it though. Make sure to fix the leak, and refill the system with the correct fluid before driving it again, because transmissions are expensive!

Dec 22, 2010 | 2002 Ford F250 Super Duty SuperCab

2 Answers

Rear end whine on my 2002 ford f150 fx4 supercrew is it clutch pack?

Could be low on differential fluid, leaking from the wheel seal. The Differential gears could also be worn from low on fluid or ears was not lined up and have worn it self out.

Service the rear end, inspect the fluid's condition and measure the any play in the gears in the rear end replace is worn out.

You may buy some time by running 50% to 100% Lucas oil treatment in your rear differential. Good luck and hope your differential is not to badly worn.

Mar 06, 2010 | 2002 Ford F150 Regular Cab

1 Answer


If it is an automatic the best thing to use is chrysler automatic trans fluid Most 1998 Ford F150s take Mercon V...also check for leak. The transmission dipstick is located on the passengers side rear. Near the firewall / or back of the engine. The dipstick is color yellow or red. use long funnel.

Sep 02, 2009 | 2000 Cadillac Catera

1 Answer

1990 ford f150 won't shift into overdrive and has constant high whining sound while in motion. Problem came on suddenly 2 days ago. Recently I changed rear drive u-joints and muffler, should be no...

Sounds like your front hubs are staying engaged, lots of problems with them on Fords, there should be a vacumm solenoid next to the battery, follow the lines down to the wheels and check for leaks. If you have a vacuum guage you can plug the line at 1 wheel and connect the guage to the other when the 4wd switch is placed from 2wd to 4wd h there should be a vacuum signal there i believe its like 12 to 15 hg and when you go back to 2wd its like 6 hg on the guage. If that dont work suspect the solenoid they are prone to water intrusion. if the vacuum signals are correct suspect on of the hubs has a vacuum leak, you need a hand held vacuum pump to test them, connect it to the vacuum port and pull a vacuum it should hold 15 hg for at least a minute, i think the actual bleed down rate is 5 hg per minute per Ford. If the hubs are leaking its a bit of work but not impossible, much cheaper to do yourself than at a shop.

Jun 18, 2009 | 2001 Ford F150 Styleside SuperCrew

1 Answer

Rear Diffrantial Leak 98' Ford Explorer

It should be that easy if the leak is from the gasket. If it from the seal, you will have to remove the drive shaft from the differential and remove the seal and put in a new one. Either way, the repair is fairly easy.

May 23, 2009 | 2002 Ford Explorer

1 Answer

Rear Differential Vibration sound when turning...

locking rear dif? door code will tell u if so may have a bad spool it's a big deal $1800.00

Apr 18, 2009 | 2005 Ford F-150

1 Answer

F150 2x4 differenyial problem.....what else can i do

Depending if it's only on one side, I would check the shock absorvers

Apr 02, 2009 | 2004 Ford F150

2 Answers

Ford Explorer leaking rear differential fluid

Time to drain and replace the fluid. The gear lube does not last long in these rear differentials. Use Valvoline 85-140 weight semi-synthetic. It will slow or even stop the leak and prevent future wear. Only replace the seals if the leak gets bad. Hint: the fill plug is 3/8" socket wrench, the drain is 3/4" socket wrench. Attach a short length of vinyl tubing to bottle to fill the differential.

Dec 14, 2008 | 2003 Ford Explorer

1 Answer

2000 gmc both rear tire oil leakage.

You are correct, it's not brake fluid. Check the level in your rear axle, it sounds like you have bad seals in the axles allowing the rear differential gear oil to leak inside the brake drums.
This is a heavy weight oil, 80 or 90 weight. This leakage will ruin your brake pads, and if enough leaks out, your rear differential will blow. The seals aren't expensive, but it's a lot of labor to pull everything apart to get at the seals, plus new rear brakes. My Ford ( and I'm sure your GMC) require removal of the rear axles to change the seals. Good Luck! countrycurt0

Sep 17, 2008 | 2000 GMC Sierra

Not finding what you are looking for?
2004 Ford F150 Logo

451 people viewed this question

Ask a Question

Usually answered in minutes!

Top Ford Experts


Level 3 Expert

80531 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22326 Answers


Level 3 Expert

5687 Answers

Are you a Ford Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides