Simple 
              Maintenance: One of the 
              simplest things that is often overlooked on our trail rigs is differential 
              maintenance.  When was the last time you swapped your diff 
              fluid and inspected your ring and pinion?  For many of you 
              the answer may be "never."  If "never" was your answer, consider that this can lead 
              to drastic problems if left unchecked - especially if you often wheel 
              in wet or muddy areas or if you spend a lot of time in rockier areas 
              where the diffs are working hard and absorbing the blunt of the 
              blows, either from the rocks (thru the tires and axles) or the drivetrain 
              itself (via your heavy right foot). 
              Perhaps you're the type that drives yours on a more frequent, 
                perhaps daily, basis and maybe you even have your oil changed at 
                one of those "quick lube" places where they change your 
                diff fluid by sucking the old fluid out, flushing the diffs (if 
                you're lucky) and then refilling them with clean fluid.   
              
              Regardless of the type of wheeler or driver that you or your 
                rig are, I would suggest pulling the cover every so often 
                (I pull mine about every 6000 miles - or about every 4 months, 
                whichever comes first)  if for no other reason than to check 
                the ring and pinion and the torque settings on the bearings.  
              
               Checking your diff is a simple job and it can be done in your driveway with 
                a few normal tools in about 30 minutes.
Checking your diff is a simple job and it can be done in your driveway with 
                a few normal tools in about 30 minutes. 
              Now, thanks 
                to our friends at LubeLocker, the entire job just got simpler and a lot cleaner.  
                These guys have used something very similar to head gasket technology 
                and placed it on a gasket for your differentials. They have taken 
                a thin sheet of steel and placed it between two layers of elastomer. 
                This "sandwich" creates a gasket that when properly 
                torqued down creates a seal between the diff cover and the mating 
                surface on the pumpkin without the use of any sealers or RTV. 
              
                
                
                  
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                    | Cross Section of the LubeLocker (From the 
                    LubeLocker website) | 
                
                
             
               Why does this make the job of changing your diffs easier then 
                ever?  Follow along as I install  a LubeLocker gasket 
                on the Dana 44 in the back of my Jeep.
              The Dirty Deed:  As you can see, my differential 
                gets a fair amount of abuse on the trails, which is one reason 
                I like to inspect it fairly often.  On my rig, the diff sits 
                far enough below the gas tank that I can access all the bolts 
                without any issues, but, if it didn't I would need to jack up 
                the body slightly and let the suspension droop a little to get 
                easy access to the bolts.
              
                
                
                  
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                    | Dana 44 diff in a 1998 TJ | Two bolts  left in place | 
                
                
               
              After I loosened all the bolts on the diff cover, I removed all but 
                two up towards the top of the cover.  Then I used a soft hammer to 
                tap on the diff cover to loosed it up on the RTV that was applied 
                during the last install.  If the soft hammer doesn't work, 
                I resort to using a screwdriver and tapping it between the cover 
                and the housing.  
              Once the screwdriver is inserted, I can 
                twist it a little and this usually separates the seal the RTV 
                has on the cover.  You may have to insert the screwdriver 
                in more then one place to completely break the seal. By leaving 
                the two screws in the cover it allows me to drain the diff in 
                a controlled manner into my catch pan without the whole cover coming off and the 
                fluid spewing everywhere.
              
                
                
                  
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                    | Using a persuader to remove cover | Screw driver inserted to drain diff | 
                  
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                    | RTV protruding thru the bolt holes | Close-up of RTV | 
                
                
               
              Once I have drained the fluid I  removed the last two cover 
                bolts and inspected what I had.  To me, everything looked good 
                inside the diff so I could now put it back together... but first 
                I had to clean up all this excess RTV.  If you look closely, 
                you can see the residue left by the RTV sealant on both the cover 
                and the diff mating surface.
              
                
                
                  
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                    | Diff mating surface.  The 
                    discoloration is RTV that must be cleaned up before reinstallation  | You need  to clean the build up off the mating 
                    surface and out of the bolt holes | 
                  
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                    | RTV on the cover. All of this will need 
                    to be cleaned | Yuck! RTV residue being peeled off of the 
                    cover | 
                
                
               
              Cleaning the RTV usually just requires a little patience. However, 
                it can be longest part of servicing your diff.  I generally 
                use a razor blade to scrape the RTV off of the surface of the cover 
                and a small scraper to clean up the mating surface on the housing.  
                I also run my hand carefully over both surfaces to look for small 
                dings or scratches or places that I may need to file down or clean 
                up before I put the cover back on.
              
                
                
                  
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                    | Cleaned mating surface | Bolts that will need to be cleaned | 
                  
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                    | Inside of cleaned cover | Cleaned up bolts | 
                
                
               
              Once I had everything cleaned up (including the bolts, because 
                I don't want to force RTV back into all of those holes), it was time 
                to lay another bead of RTV on the cover and - oh, wait, this is 
                where LubeLocker's new differential gasket comes in.  Their 
                new gasket does not require any RTV or any other material outside 
                the gasket. Great! 
              
                
                
                  
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                    | LubeLocker, and instruction sheet |