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For those of you who have installed a drain plug in your Transmission

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Thank you Black02Silverado  this is preciously what I was looking for. I was not sure how much space was in the pan once bolted in to the inner workings. This gives me the info I needed, Thank You

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14 minutes ago, 64BAwagon said:

That was exactly my plan too. Could you share the part number from Summit ?   I have read reviews on some plugs that they werent heavy enough and they warped when welded. I have a friend thats a pretty good TIG welder and I was planning on having him do it. 




Part Number: AAF-ALL50735

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Adding a drain plug is one of the first things I do on every transmission I have to service.


I take a regular nut and castle it with a cut-off wheel.  The slots allow fluid to drain; without them, any lip formed by the drain plug retainer will hold fluid, and more importantly, settled particulate (which never comes out with an extraction pump).


Then I drilled a hole in the pan at a location that wouldn't interfere with either the magnet or the filter.


Then I MIG welded the castle nut, slot-side down, above the hole.  I used a new drain plug to center the nut and clamp it down for a brief tack.


Drain bolts, with sealing washers, are readily available from any FLAPS, either 14 or 15mm hex head (I forget which).  This is also the upgrade I highly recommend for anyone with a BMW; toss the 8mm allen drain bolt as far as you can throw it and replace with a GM drain bolt.


Now, ATF changes are far simpler and easier than even dicking around with a fluid pump; remove drain bolt, let fluid drain while you walk away.  Slightly pull dipstick to allow air.  Come back, wipe pan, install bolt, fill trans, done.  Easier and quicker than engine oil.


The principal that I use for every machine I own is that maintenance prolongs their lives, and maintenance will occur more often when it is easy and convenient.  Therefore, ease of maintenance prolongs a machine's life. 😉






Edited by 16LT4
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@16LT4 Got my thinking gears going. 


How To Make Simple Dimple Dies for Sheet Metal (roadkillcustoms.com)


When you make the dies they can be any size. Turning a threaded female plug is easy enough. TIG in place. More work? Yep. But the dimple allows next to everything draining. It also allows any depth thread you feel is secure and for the ******, a means to safety wire the plug in place. 



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