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General Tech Transmission Drain Plug Too Tight?


Luke Skywalker
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Did someone here once say that over-tightening the drain plug on the bottom of the transmission can crack the casing along the seam? I used a breaker bar (for convenience only) and went "easy as it goes," but it kept going. I stopped at a point that seemed like 20 to 25 foot pounds of torque. I just wanted it snug relatively tight since I've seen it leak. I did use a pipe thread sealing tape (yellow). Am I at risk of harming that casing?


Luke Skywalker
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Not the best design with the iron plugs and aluminum case. The case, of course, is the weakest part. Pipe thread torque has lots of variables and is usually not used. Always use sealer, which you've done.
This might help:




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20 is a lot higher than I tighten them. I've never checked, but 10-12 ftlbs would be closer. I'd rather the occasional drip than having to drill them out, as I've had to do many times thanks to PO's!!


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Although hard to describe and I have no idea how it translates to ft/lbs, I have always tightened down drain plugs with what I would call medium strength I guess, exerting a bit of strength until it stops, but not then applying the extra force/leverage you might when you, say, tighten down a lug nut. The thread tape is a good idea if little drips are troublesome to you.

I am somewhat compulsive about everything working on my cars as designed, but I have convinced myself that they were designed to leak a little.....


Darth Vader
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Anytime there is low torque specs use a 3/8 drive, never a torque wrench, as a person can snug to 40 easy with 3/8 drive. Use 1/4 drive on aluminum with low torque figures or rockers. The small wrench will somewhat lower risk of over tightening. But if necessary, check your torque with torque wrenches similar in size to what you are tightening.
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