Automatic drain plug where to find or replace?
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Joined: Mar 2022
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From: Pocatello, ID
Automatic drain plug where to find or replace?
Hey everyone I'm new to this but I figured I'd try! I own a c5 2002 corvette and I recently did a transmission service on it. I have the automatic 4 speed but the fill plug is almost stripped. I want to know if there is a replacement? aftermarket? Used? I have no clue and I've checked everywhere I live! Any information is great! I know the bolt size is 21 or 22mm for the socket, thanks in advance!!
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What part of which plug is stripped, the hex or the threads? Your Thread says drain plug, but your description says fill plug. I'll assume fill plug, as I dont recall any drain plug, at least on the pan. I'm guessing the hex, since you're not sure of the size, and the thread size would be tough to strip. I'm not sure of the thread size, or type, as I never had an issue with it when I changed my ATF in 2014. Im sure someone will chime in with the size. If I had to guess, Id say its a 3/8" or 1/2" straight pipe thread. Does it have an O-ring? Have you checked the Chevy dealer? If they don't have it, I'm sure they could give you the proper dimensions, and you could get it from Grainger, McMaster-Carr, etc. As a last resort, you could try a trans repair shop. Hope this helps.......
Last edited by Vetteman Jack; Mar 16, 2022 at 11:21 AM.
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Actually, IIRC, you can fill the auto thru the lower plug. I know that's how I did it. You MUST leave the car running to accurately check the level. IIRC (yup, another one!!), you have to add several quarts with the engine off FIRST. That ensures there's enough fluid that no internal damage occurs. Then, when you've added enough that it comes out the lower plug, replace the plug and start the car. Do NOT shut engine off again until you're completely done, or youll shower with ATF!!! Get back under the car, then remove the plug again, and fill until fluid is running out the hole. Replace the plug, again, get into the car and shift thru all the gears, leaving it in each gear for 5 or 10 seconds, then put it in Park, get under the car, remove the plug, and fill again, if needed, until fluid comes out the lower plug. Insert the plug, tighten, and you're done. I'm going off memory here, and I did this in 2014, so you may want to double check my advice, since I don't have my shop manuals in front of me, and it's been 8 years, so.......
