Third Member Rebuild

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dmowrey3@comcast.net
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Third Member Rebuild

Post by dmowrey3@comcast.net »

Has anybody ever used a local shop to rebuild their Third Member and if you did what was the out come ? I would like to go to a local guy that rebuilds differential but not sure if the Dodge third member is a different animal !!!
just me
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Re: Third Member Rebuild

Post by just me »

It is a different animal. It tKes a HUGE vise, special fixtures, special tools, and special procedures. If you can make or obtain the tools, it isn't too difficult. But, it is very different than your average diff.
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dmowrey3@comcast.net
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Re: Third Member Rebuild

Post by dmowrey3@comcast.net »

just me wrote:It is a different animal. It tKes a HUGE vise, special fixtures, special tools, and special procedures. If you can make or obtain the tools, it isn't too difficult. But, it is very different than your average diff.
That what I thought,,,,Thxs
just me
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Re: Third Member Rebuild

Post by just me »

My favorite bit in the instructions is to heat the case with a torch until it is hot enough for solder to melt when touched to the side, then using the fixture and suitable tool strike and unscrew the carrier.
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Re: Third Member Rebuild

Post by Elwood »

dmowrey3@comcast.net wrote:Has anybody ever used a local shop to rebuild their Third Member and if you did what was the out come ? I would like to go to a local guy that rebuilds differential but not sure if the Dodge third member is a different animal !!!
You might find this thread over at PWA to be useful: http://www.powerwagonadvertiser.com/for ... 623&page=6. The third member in the flat fender Power Wagon is essentially the same as the M37.
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dmowrey3@comcast.net
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Re: Third Member Rebuild

Post by dmowrey3@comcast.net »

Elwood wrote:
dmowrey3@comcast.net wrote:Has anybody ever used a local shop to rebuild their Third Member and if you did what was the out come ? I would like to go to a local guy that rebuilds differential but not sure if the Dodge third member is a different animal !!!
You might find this thread over at PWA to be useful: http://www.powerwagonadvertiser.com/for ... 623&page=6. The third member in the flat fender Power Wagon is essentially the same as the M37.
Thanks Elwood
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Re: Third Member Rebuild

Post by Kaegi »

bob stahl rebuilds them at a decent price and upgrades the side gear thrust washers to bronze. stocks ones are fiber and wear out with lots of trail use. fiber ones last a long time obviously but bronze is better .
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Re: Third Member Rebuild

Post by MSeriesRebuild »

just me wrote:My favorite bit in the instructions is to heat the case with a torch until it is hot enough for solder to melt when touched to the side, then using the fixture and suitable tool strike and unscrew the carrier.
The above quote is what the manual says, however it is not a good method to use at all. Striking the case cap to break it loose after warm up can warp it rather easily. When this happens it is trash for the scrap bin. The case/cap assembly is a precisely machined and matched component piece. Once it is warped, it is impossible to get a precise & true running set up. It should be mounted securely in an appropriate fixture, warmed to approx. 600 degrees over the full circumference around the case/cap mating area, then use a special socket designed to fit the cap structure and a long bar to break it loose gently. Another issue worthy of note is to be very careful not to over heat the assembly during the warm up phase. If the assembly is over heated, that destroys the interference fit of the case/cap forever. You will also notice after the cap is removed, there will be upward bumps at the 3 areas just above the tapered pin holes in the end of the case that lock the cap in place. To fix this, VERY CAREFULLY file these high spots down to the exact level of the case top, being careful not to cut too much or get the top of the case out of level. Cutting too much here (creating low spots) is as bad as not cutting at all. If this step is not followed carefully, the cap will not go back down evenly and completely against the edge of the case. Removing these 3 high spots will most likely necessitate the drilling of new taper pin holes in the case to match the pin holes in the cap as they will no longer line up as original after the bumps are removed. This requires precision drilling methods using a "C" (.242") drill bit. We perform this step by setting up the unit in a milling machine, which makes it a fairly simple procedure. I have done this step in a drill press, but the much better precision of setting it up in the mill for drilling makes this step much easier and more precise. Any issue overlooked on a precision assembly such as this will affect the gear set up in the end, which is life and death critical in a hypoid gear set up. It can mean the difference in a smooth running, long life set up or a noisy, short lived set up. The manual does not cover many of these very important details & steps required for building a differential to the best it can be for the long haul. We offer diff rebuild service "with extreme care". Many of the units we build are going into our Cummins powered rebuilt trucks. Even the slightest mishap in a hypoid gear unit set up going into an application with a 75/80 MPH top end capability will shine out quickly in the road testing phase of a build. Better to take the time and material to DO IT RIGHT than to realize during road testing that you must go back into the unit to correct steps that should have been addressed during the initial diff rebuild process.
Charles Talbert
www.mseriesrebuild.com
dmowrey3@comcast.net
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Re: Third Member Rebuild

Post by dmowrey3@comcast.net »

Not for the faint of heart that's for sure ,,,,, Thank you Charles for shedding light on the subject .
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