Leaking transmission pan plug

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ChuckN

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Quick question- I put a trans pan with a drain plug on the TH350 when I did the shift kit. Sure enough, the plug leaks oil. Maybe the convenience of the plug is outweighed by the fact that it’s a piece of junk.

The plug just has a plastic washer. Maybe a rubber washer? Thread sealer? Teflon tape? Ideas? Thanks in advance.
 
ChuckN

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CheemsK1500

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I would try an appropriate size rubber washer and teflon tape on the existing bolt. While it kind of defeats the purpose, as a final resort, you could just JB Weld the drain plug into the pan if you do not want to go through the trouble of changing the pan again. I have never really worried too much about auto transmission drain plugs. I figure, if I am changing the fluid, I might as well change/clean the filter too while I am at it. A plug does make draining a little cleaner process though.
 
AuroraGirl

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i would definitely determine the method of sealing. taper, washer, o ring, threads, etc. it maybe just needed more torque! Or the threads were junk and it went in off kilter, etc. so you need to drain it. get a clean oil pan so you can reuse
 
ChuckN

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CheemsK1500 said:
I would try an appropriate size rubber washer and teflon tape on the existing bolt. While it kind of defeats the purpose, as a final resort, you could just JB Weld the drain plug into the pan if you do not want to go through the trouble of changing the pan again. I have never really worried too much about auto transmission drain plugs. I figure, if I am changing the fluid, I might as well change/clean the filter too while I am at it. A plug does make draining a little cleaner process though.
Click to expand...
Yeah, truth be told, it was one of those purchases you run across. And it was chrome! Lol…

I’ve used Teflon tape before on prior vehicles. I had a CRD Jeep Liberty that had a problematic drain plug from PO over tightening the plug, Teflon did the trick.

I did happen across a problem that people were having with this particular pan that the plug was too deep and was bottoming out on the filter before they could get a seal. I checked mine out and it doesn’t hit the filter, probably due to the thicker Moroso pan gasket providing more clearance.

While I have it drained, it’s an obstacle blessing that I can get to work on re-routing the trans cooler/ lines.
 
justhorns

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Also, try Gasoilia... it's a sealant for such fluids. But, you have to pull the plug and clean, so a full drain. Either way, it's better than dropping the pan while it's full. Yik. I may have that name screwed up, but, it's a green paste.
 
ChuckN

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FYI, what I ended up running across at NAPA was a drain pan bolt that matched the threads that was just a bolt with a large shoulder around it and had a formed rubber gasket molded onto it. We’ll see how that goes, and if it still leaks I will definitely try any of those suggestions. It’s funny what options a guy will run across when you ask them to bring out the whole box and start digging around.

*edited- damn autocorrect, meant “options”.
 
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ChuckN

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WesN said:
Did the pan come from a place named after the top of a mountain?
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They sell it there, but I don’t think it’s branded by them. I think it’s some Spectre piece of junk.
 
AuroraGirl

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ChuckN said:
FYI, what I ended up running across at NAPA was a drain pan bolt that matched the threads that was just a bolt with a large shoulder around it and had a formed rubber gasket molded onto it. We’ll see how that goes, and if it still leaks I will definitely try any of those suggestions. It’s funny what options a guy will run across when you ask them to bring out the whole box and start digging around.

*edited- damn autocorrect, meant “options”.
Click to expand...
When I worked at the tire shop, I was surprised at the very large selection of drain bolts that we had in stock to fix oopsies and just to fix bad gasketing situations etc. They also had a few repair ones which are oversized meant for the most egregious of oem situations either by volume of occurance or poor engineering lol. That was only a small bit compared to the ocean im sure thats out there
 
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AuroraGirl said:
When I worked at the tire shop, I was surprised at the very large selection of drain bolts that we had in stock to fix oopsies and just to fix bad gasketing situations etc. They also had a few repair ones which are oversized meant for the most egregious of oem situations either by volume of occurance or poor engineering lol. That was only a small bit compared to the ocean im sure thats out there
Click to expand...
Dorman used to make an oversized and double oversize drain plug, besides the standard size. IIRC it was a 1/2" SAE threads at standard, that was a common oil pan drain plug back in the 60s/70s....
Dorman parts didn't always have the fitment and quality issues they have lately. The brand used to be quality American made parts and automotive hardware. Used to be, any good parts store had the orange drawers under the counter, that had all sorts of problem solvers. BTW those drawers have a certain smell to them too!
 
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