Front differential cover removal???

[Summajet]

I am getting ready to replace my failing front differential assembly. What is the best procedure to remove the front differential cover and not break the cast aluminum housing????
I have removed all the bolts.

I read it is best to use Black RTV sealant when reinstalling the front differential cover.
Any advice would be appreciated.
Thanks!

 

[410Fortune]

Allright I know you have already removed the diff from the vehicle because you said you removed all of the bolts
So now you just need to carefully pry the cover off it is being held on with silicoln
Get something strong and flat underneath a TOP corner and begin to pry it off of the housing...it will come off. Sometimes it helps to pry in two or three different locations. I say start at the top because if you do gouge the aluminum housing of bend the cover slightly you want the damage up high where it wont cause a leak

I use Permatex Ultra Grey to re seal these housings, that stuff is awesome. Black or orange silicoln will also work, but the ultra grey is worth a little extra $$$$

Make sure both surfaces clean and dry
Good time to replace both axle shaft seals........and check the vent line, make sure it is clear and not plugged up with gunk

 

[CDW6212R]

Exactly on all of that. Do the axle seals and be very careful installing them and the axles when it goes back together. Those axle seals are a big PITA if you have to replace them on the vehicle. They are fairly easy to do with the housing out.

 

[C420sailor]

Pinion seal is easier on the bench too. I did all three the last time I had my front diff out and now it doesn’t leak a drop. Magical.

 

[CDW6212R]

Pinion seal is easier on the bench too. I did all three the last time I had my front diff out and now it doesn’t leak a drop. Magical.

Very good. What did you use to loosen the pinion nut? I've only changed one of those seals, and it was on the truck with the tires on the ground. I have a new Dewalt impact gun but I'm not sure it will pull that nut.

 

[C420sailor]

I used an air impact. It wasn’t on as tight as I expected, on either of my Trucklets. I think my cordless impact would’ve done the trick, too...not sure, as mine isn’t very good.

I marked the nut/yoke/shaft and counted the exposed threads past the nut, and simply returned everything to those settings on reassembly—tens of thousands of miles since then with zero issues.

 

[CDW6212R]

Very good. That's what I did with my 99 while I reconstructed it. I did everything I could before ever driving it. The pinion seal showed a little leak, so I marked the nut and like you, returned it to the same spot.

These front diff's are reliable, but the fluid and seals need to be replaced sometimes.

 

[RickOTR]

This is what I use...

 

[410Fortune]

My dewalt Impact WILL EASILY do the pinion nuts
She will rip up to 1200 ft lbs
20V brushless impace with 1/2" anvil, we call her "Hank"
Basically has replaced my air impact and I do not even run the compressor unless I am cleaning parts or filling tires

https://www.amazon.com/dp/B00FREST98/?tag=serious-20

I think I got it for less then $400? It was a while ago now they are over $600???? What the heck?? Have to look for deals

 

[CDW6212R]

My dewalt Impact WILL EASILY do the pinion nuts
She will rip up to 1200 ft lbs
20V brushless impace with 1/2" anvil, we call her "Hank"
Basically has replaced my air impact and I do not even run the compressor unless I am cleaning parts or filling tires

https://www.amazon.com/dp/B00FREST98/?tag=serious-20

I think I got it for less then $400? It was a while ago now they are over $600???? What the heck?? Have to look for deals

Psst, it's been on sale recently, I paid $200 for it from Lowe's last week. The tool only was $200 or slightly more, but the kit was the one on sale, tool/battery/charger/bag for $200).

I see it's gone back off sale at Lowe's, now it's $319, Model #DCF899M1; https://www.lowes.com/pd/DEWALT-XR-...ss-Impact-Wrench-1-Battery-Included/999947862

EDIT; BTW, I got an email today for a Monday discount on Acme Tools, for $20 off. I checked on that Dewalt big impact, everything is out of stock, but the system will take an order for the current prices. The bare 700/1200lbft 1/2" impact tools are $219, and the kit I bought is still $199(DCF899M1). The discount code GREEN20 is accepted for the kit, so it may be possible to order it for $179.

 

[imp]

I used an air impact. It wasn’t on as tight as I expected, on either of my Trucklets. I think my cordless impact would’ve done the trick, too...not sure, as mine isn’t very good.

I marked the nut/yoke/shaft and counted the exposed threads past the nut, and simply returned everything to those settings on reassembly—tens of thousands of miles since then with zero issues.

This is most important, to assure bearing preload is not altered by disassembly. If ANY part other than seal or oil slinger is replaced, preload must be addressed to assure longevity; re-tightening to previous location will not cut it.

 

[Summajet]

Allright I know you have already removed the diff from the vehicle because you said you removed all of the bolts
So now you just need to carefully pry the cover off it is being held on with silicoln
Get something strong and flat underneath a TOP corner and begin to pry it off of the housing...it will come off. Sometimes it helps to pry in two or three different locations. I say start at the top because if you do gouge the aluminum housing of bend the cover slightly you want the damage up high where it wont cause a leak

I use Permatex Ultra Grey to re seal these housings, that stuff is awesome. Black or orange silicoln will also work, but the ultra grey is worth a little extra $$$$

Make sure both surfaces clean and dry
Good time to replace both axle shaft seals........and check the vent line, make sure it is clear and not plugged up with gunk

I was able to get the cover off easy. I used some kroil spray and soaked the cover-case at the top twice. It was very easy to remove the cover.
Upon opening the used differential, the gear oil was normal in appearance and no burn smell or signs of overheating. I replaced the two axle seals. The pinion seal was not leaking. I used the permatex ultra gray and cleaned both surfaces before applying the gray permatex.

I let is cure in the house yesterday/night. I got the case installed and as mentioned the two nuts for the differential had came off. I used a set of long pliers and it was not that bad. When removing the vent hose it split about 3" in length. I went to the local junk yard and got a good vent hose. The hose was not clogged. I put some dielectric grease on the inside of the vent hose and getting it onto the case was not bad. I got it installed back in. I am giving it till tomorrow before adding the gear oil.

I popped the cover off the original differential that was built with my truck, I will get some pictures taken and post. Looking inside the drivers side of the differential it appears the teeth are worn down. I also noticed on the cv axle shaft from that the inboard splines were rounded down some. Passengers side i was able to remove the male shaft tube from inside the differential case. The clip on the spline tube was broken off.

What is the torque value for the cv axle nut? I thought it was like 165 ft/lbs?
Thanks

 

[CDW6212R]

Those axle nuts are high torque large nuts, about 225lbft. If any of the gears in the diff, are worn a lot, what size have the tires been over the past few years. Is that a 4WD V6 or an AWD V8?

 

[Summajet]

Those axle nuts are high torque large nuts, about 225lbft. If any of the gears in the diff, are worn a lot, what size have the tires been over the past few years. Is that a 4WD V6 or an AWD V8?

It is a V8 awd. Tire size always used is 235/75/15.
Tires replaced new two years ago. I don't mismatch tire brands it sizes as I know it can cause issues with awd

 

[CDW6212R]

It is a V8 awd. Tire size always used is 235/75/15.
Tires replaced new two years ago. I don't mismatch tire brands it sizes as I know it can cause issues with awd

That is good. I had to replace the front diff, on my prior 98 AWD because of the transfer case locking up, and taking out the diff. The prior owner mixed tires and at some point removed the front driveshaft. The TC fluid was always black, I learned along the way that the AWD viscous clutch is a sealed unit, and the fluid inside that is black.

So if you ever change an AWD TC fluid and noticed it's very black, it's time to suspect the vehicle has had mismatched tires on it for a time. I believe that once the viscous clutch has some leakage, it's because the seals on it have gotten too hot, and they will continue to leak until the unit locks up.

 

[Summajet]

I have gotten the used front differential installed. New motorcraft axle seals. I had purchased cv axles from advance Auto, CARQUEST brand. I reinstalled the front driver and passenger cv axles that were in the truck when new.
No leaks on the bellhousing cover or axle seals, no more vibrations or pinion gear noise.
I also replaced the two front brake calipers as a pair set. The driver side was easy to get the brake line off. The Passenger side was stubborn. I used some heat on the passenger side brake line nut and it came loose.
Used the harbor freight vacuum tank and pulled out the old brake fluid. Wife push the pedal while I bled the brakes. Getting alignment today.

I had replaced the valve covers and made sure it was free of oil and the covers were not bent. I used the fel pro blue cover gaskets. I noticed the driver side rear valve cover gasket is leaking. I assembled the blue gaskets without any gasket sealer. Anyone else had this issue and if so what was your fix?

Thanks!