Do i need to use silicone when installing the gasket on the rear differential?

4.2L Engine

1. Before servicing the vehicle, refer to the Precautions Section.
   WARNING
   During engine repair procedures, cleanliness is extremely important. Any foreign material, including any material created while cleaning gasket surfaces, that enters the oil passages, coolant passages or the oil pan can cause engine failure.
2. Raise and safely support the vehicle.
3. Remove the starter.
4. Drain the engine oil. Install the drain plug when finished.
5. Remove the 4 bolts and the crossmember.
6. Remove the 3 oil pan-to-transmission bolts.
7. Remove the 17 bolts and the oil pan.
8. Remove and discard the oil pan rear seal.

To install:

WARNING
Do not use metal scrapers, wire brushes, power abrasive discs or other abrasive means to clean the sealing surfaces. These tools cause scratches and gouges which make leak paths. Use silicone gasket remover and a plastic scraping tool to remove all traces of old sealant. Follow the directions on the packaging.

1. Clean the gasket mating surfaces using silicone gasket remover, a plastic scraping tool and metal surface prep. Follow the directions on the packaging.
   NOTE
   If the oil pan is not secured within 4 minutes, the sealant must be removed and the sealing areas cleaned. To clean the sealing area, use silicone gasket remover and metal surface prep. Follow the directions on the packaging. Failure to follow this procedure can cause future oil leakage.
2. Apply silicone gasket and sealant to the oil pan sealing areas shown and install the oil pan rear seal.
3. Apply silicone gasket and sealant to the rear main bearing cap.
4. Install the oil pan rear seal.
5. Apply a bead of silicone gasket and sealant to the oil pan mating surface.
6. Position the oil pan and install the bolts. Tighten the bolts in the sequence shown. Tighten to 10 Nm (89 inch lbs.).
7. Install the 3 oil pan-to-transmission bolts. Tighten to 34 Nm (25 ft. lbs).
8. Install the starter.
9. Position the crossmember and install the 4 bolts. Tighten to 90 Nm (66 ft. lbs.).

4.2L Engine

1. Before servicing the vehicle, refer to the Precautions Section.
   WARNING
   During engine repair procedures, cleanliness is extremely important. Any foreign material, including any material created while cleaning gasket surfaces, that enters the oil passages, coolant passages or the oil pan can cause engine failure.
2. Raise and safely support the vehicle.
3. Remove the starter.
4. Drain the engine oil. Install the drain plug when finished.
5. Remove the 4 bolts and the crossmember.
6. Remove the 3 oil pan-to-transmission bolts.
7. Remove the 17 bolts and the oil pan.
8. Remove and discard the oil pan rear seal.

To install:

WARNING
Do not use metal scrapers, wire brushes, power abrasive discs or other abrasive means to clean the sealing surfaces. These tools cause scratches and gouges which make leak paths. Use silicone gasket remover and a plastic scraping tool to remove all traces of old sealant. Follow the directions on the packaging.

1. Clean the gasket mating surfaces using silicone gasket remover, a plastic scraping tool and metal surface prep. Follow the directions on the packaging.
   NOTE
   If the oil pan is not secured within 4 minutes, the sealant must be removed and the sealing areas cleaned. To clean the sealing area, use silicone gasket remover and metal surface prep. Follow the directions on the packaging. Failure to follow this procedure can cause future oil leakage.
2. Apply silicone gasket and sealant to the oil pan sealing areas shown and install the oil pan rear seal.
3. Apply silicone gasket and sealant to the rear main bearing cap.
4. Install the oil pan rear seal.
5. Apply a bead of silicone gasket and sealant to the oil pan mating surface.
6. Position the oil pan and install the bolts. Tighten the bolts in the sequence shown. Tighten to 10 Nm (89 inch lbs.).
7. Install the 3 oil pan-to-transmission bolts. Tighten to 34 Nm (25 ft. lbs).
8. Install the starter.
9. Position the crossmember and install the 4 bolts. Tighten to 90 Nm (66 ft. lbs.).

Suggest to remove cover and replace gasket with Permatex Gasket Maker Silicone. Fully clean and dry apply a 1/4 bead on cover and bolt down to 20 ft lbs. go around several times to compress silicone. Let silicone cure 30 minutes then refill.

Well, at this point, you're probably overdue for a fluid change anyway. Drain the rear differential, take the cover off, clean the surfaces, make a new gasket out of red RTV silicon (Here's how: run a bead all the way around the inner surface. Put on the differential cover, all the bolts, and then pull the cover back about a quarter of an inch. Let it dry. It is now a self-made gasket that will actually crush and hold tighter than if it is simply squashed in while wet.), refill the differential, and you should be good to go. A little oversimplified, but still, main steps!

The cover gasket is silicone and is not designed to be serviced without removing the differential assembly.You will need to remove axles , driveshaft , and maybe the spare tire to get differential out.

put flat pan under the housing remove the bolts holding the cover usually 10 or 12 (1/2 or #12 metric) bolts? allow the rear end grease to drain... then scape off the old gasket clean with brake cleaner spray install either new gasket or form one with oil resistant silicone put the cover back on , dont refill the fliud for at least 12 hours if using silicone. Also check the front driveshaft rear end yoke seal....they sometimes leak making the illusion of a rear end pan cover leak...if that is leaking you remove the shaft carefully...remove the large yoke retaining nut, replace the press in seal...be sure retaining yoke nut is properly torqued when reinstalling .

Not that difficult, raise and support the rear of the truck and remove the wheels. Might as well replace both sides so you know you have new seals, remove the differential cover and drain the fluid. Once differential is opened and cleaned , remove the axle "C" clip that hold the axle in place and slide the axle out. Once the axle is out remove the wheel seal and clean around the area. This would be a good time to replace the wheel bearing too since you have access to them and there not that expensive. Install the new bearing and seal, note make sure you oiled the bearing and seal before installing it back and take care when installing the axle back in and "C: clip. Use RTV silicon gasket maker to seal the differential cover and wheels back on and lower. If your lazy like i am, you can drain the differential fluid and replace it with a 50/50 mix with gear oil and Lucas engine oil additives. That may stop the leak and get you a few more miles. You gear oil is (ford 75W-140) (Dana 80W-90)and the capacity is 2.6 liters and 3.5 liters if you have the 10.25 Ring gear. Good luck and hope this helps.

Section 05-02A: Axle, Integral Carrier — 8.8-Inch Ring Gear 1994 Town Car, Crown Victoria/Grand Marquis. Workshop Manual REMOVAL AND INSTALLATION Axle Shaft NOTE: Whenever replacing the rear axle lubricant, use Rear Axle Lubricant XY-90-QL (ESP-M2C154-A) or equivalent.
Removal
CAUTION: The rear brake anti-lock sensor must be removed before the axle shafts are removed. The rear brake anti-lock sensor is bolted on the rear disc brake caliper anchor plate.

1. Raise vehicle to desired working height. Refer to Section 00-02 . Remove rear wheel (1007) and tire assembly. Remove rear disc brake calipers (2552) and rear disc brake rotors (2C026) .
   
   
   
   
   

1. Clean all dirt from area of axle housing cover with a wire brush and/or cloth.

1. Drain rear axle lubricant by removing the axle housing cover .

1. Remove differential pinion shaft lock pin and differential pinion shaft .
   
   
   
   

1. Push flanged end of the axle shafts toward the center of the vehicle and remove the rear axle shaft retaining u-washer from the button end of the axle shaft .
   
   
   
   

1. Remove axle shaft from the rear axle housing , being careful not to damage the inner wheel bearing oil seal (1177) and rear brake anti-lock sensor ring.

Installation
NOTE: Check for presence of rear axle shaft o-ring (4A332) on the spline end of the shaft and install if not present.
CAUTION: Care must be taken not to let axle shaft splines damage oil seal or bearing assembly.

1. Carefully slide axle shaft into rear axle housing without damaging rear wheel bearing (1225) or rear brake anti-lock sensor indicator (2C189) . Start splines into side gear and push firmly until the button end of axle shaft can be seen in the differential case .

1. Install the rear axle shaft retaining u-washer on the button end of the axle shaft splines, then pull the shaft outboard until the shaft splines engage and the rear axle shaft retaining u-washer seats in the counterbore of the differential side gear .

1. Position the differential pinion shaft through the differential case and differential pinion gears , aligning the hole in the differential pinion shaft with the lock bolt hole. Apply Rear Axle Lubricant to differential pinion shaft lock pin . Install differential pinion shaft lock pin and tighten to 20-41 Nm (15-30 lb-ft). CAUTION: Differential pinion shaft lock pin must be tightened to specification using Stud and Bearing Mount E0AZ-19554-BA (WSK-M2G349-A1) or equivalent.
   
   
   
   
   NOTE: Axle housing cover must be installed within 15 minutes of application of the silicone rubber or new silicone rubber must be applied.
   CAUTION: Make sure machined surfaces on both axle housing cover and rear axle housing are clean before installing the new silicone sealant. Inside of axle must be covered when cleaning the machined surface to prevent axle contamination. Tighten the cover bolts in a crosswise pattern to ensure uniform draw on axle housing cover .
   

1. Apply Silicone Rubber D6AZ-19562-AA or BA (ESB-M4G92-A or ESE-M4G195-A) or equivalent. Install axle housing cover and tighten retaining bolts to 28-38 Nm (38-52 lb-ft).
   
   
   
   

1. Add Motorcraft Rear Axle Lubricant XY-90-QL or KL (ESP-M2C154-A) or equivalent until it is 6-14mm (1/4-9/16 inch) below bottom of fill hole. Add 118.3 mL (4 oz) of Ford Additive Friction Modifier C8AZ-19B546-A (EST-M2C118-A) or equivalent to Traction-Lok axles. Install fill plug and tighten to 20-41 Nm (15-30 lb-ft).

1. Install rear brake anti-lock sensor indicator . Tighten retaining bolt to 4.5-6.8 Nm (40-60 lb-in).

1. Install rear disc brake caliper and rear disc brake rotor .

1. Install wheels and tires.

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1. Insert Rear Bearing Remover T85L-1225-AH in bore and position it behind bearing so tangs on tool engage bearing outer race. Remove rear wheel bearing and inner wheel bearing oil seal as a unit, using Impact Slide Hammer T50T-100-A.
   
   Rear Disc Brake Caliper Anchor Plate
   
   
   
   
   

1. Lubricate the rear wheel bearing with Rear Axle Lubricant.
   
   
   
   

1. Install rear wheel bearing into the housing bore using Axle Tube Bearing Replacer T78P-1225-A.
   
   
   
   CAUTION: Installation of rear wheel bearing or inner wheel bearing oil seal assembly without proper tool may result in an early bearing or seal failure. If inner wheel bearing oil seal becomes cocked in bore during installation, remove it and install a new one.
   

1. Install the inner wheel bearing oil seal using Axle Tube Seal Replacer T78P-1177-A. Use Premium Long-Life Grease XG-1-C or K (ESA-M1C75-B) or equivalent between the lips of the inner wheel bearing oil seal .
   
   
   
   

1. Install axle shafts as outlined.

To change gear lube, you will need to remove the cover. While in there, wipe out the bottom of the case with a clean rag to remove any debris in there. Remove any gasket material remaining on the cover and housing and use a good silicone sealer on the new gasket. Re-fill on flat ground and don't put too much in (just to fill hole)

No big job Really. Just locate your Drain Plug for the Oil. Thepan is right there, Remove the Bolts around the Pan and Remove. You will lose all of your oil so, Have something there to catch it all. Clean it all around the Edges of the Block where the Pan mounts with Degreaser and Make sure that you Scrape the Old Gasket off of Both the Block and the Pan. Run a Thin Bead of Blue ATV Silicone around the Pan Edge, Lay the Gasket on top of this Silicone. Put another Thin line on top of the Gasket and Reinstall. This Silicone is High Temp Silicone and will Seal Very Well. Make sure to put oil Back in the Motor! Please Rate my Response, I need all the Help That I can Get! Thanks!