Today while starting to change the gear oil in my Bronco, I could not find the drain plug as described in my service manual. I found the fill plug about halfway up, but not a lower drain plug. I would appreciate any Ford experts that would inform me on how to drain the rear end oil.

Thanks for the help.

 

There is no drain plug on 9"axle housing; unless you put one there. To completely drain the axle assembly: remove wheels, brake drums & you will see under each axle flange there is a (4) bolt flange. Remove the (4) locknuts @ this flange, strike center of axle flange with 3-5lb. hammer--thus loosening the axle shaft. Slide axle shaft's out of each side. remove u-bolts or straps @ pinion yoke on diff. There are 10 nuts that hold 9" diff carrier assy. into axle hsg.--remove these, put a pan under center of 9" carrier & gently tap a screw driver between axle housing & axle carrier. Diff. will allow you to drain the lube out. Remove complete carrier, scrape-off old gasket, rinse axle tubes, from outside to inside. Clean tubes w/ brake parts cleaner or some other good non-flameable cleaner. Inspect center carrier (diff.); if everything looks good--re-install it, using a good silicone sealer & check axle brg's, seals. Re-install axles & seals & refill diff. with proper lube. Note, refill diff @ level position, let veh. sit for 5 min.--then elevate one side--letting oil permeate into other axle tube--then bring axle assy. back to level & check lube. Repeat this procedure for other side of axle tube--getting oil out into axle tube.
In the past, I have drilled a hole in the bottom of the axle hsg. (with diff. out) for future lube changes and tapped it or welded a short pipe thread coupler. Another great idea is to install a small magnet @ bottom of axle hsg.--before re-installing 3rd. member. Also, don't lose the tag (which should have been bolted @ 10 O' clock @ diff. mounting). This tag has important info- espicially ratio, spline info & ability to identify the drive yoke on diff.

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1999 teal blue f150 s/c
4.6l, xlt, 3.55 L/S
Tow pkg., rhino liner, engine block heater & hard toneau cover. single c.d.
255/75 r16 Generals-owl

 

Don't they sell a little suction pump gun for draining differentials? You stick the hose down through the fill hole and suck the oil out?

 

Yes, buy a suction pump at JCWhitney for $9.

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2000 F-150 XL,RC,LB,5.4,4R70W,3.55LS,
Class III tow/Payload #3/Convenience pkgs.,
4-wheel disc/ABS,Chestnut/Parchment 40/60,
Ford bedliner & gas/wheel/spare locks,
3" cold air box modification, Superchip,
Dynomax ultra-flow welded 3" cat-back,
3" exit Y-pipe, Hellwig rear anti-sway bar.

 

A suction pump will drain the diffrential grease out but won't collect the wear particles from the bottom of the housing. You got to do the job like gearmanx17 says to get in there and clean it properly.

 

I agree 100% that the best method is a magnetic drain plug. If you are not ready for a complete rear end tear down, the suction method can easily change the gear oil, and has been known to work well for many years/miles of service. I have also seen people carefully drill and tap small pipe threads and install a plug without taking the rear apart. I believe there are several methods and thoughts on this issue. Sorry for the confusion on my part.

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2000 F-150 XL,RC,LB,5.4,4R70W,3.55LS,
Class III tow/Payload #3/Convenience pkgs.,
4-wheel disc/ABS,Chestnut/Parchment 40/60,
Ford bedliner & gas/wheel/spare locks,
3" cold air box modification, Superchip,
Dynomax ultra-flow welded 3" cat-back,
3" exit Y-pipe, Hellwig rear anti-sway bar.