I recently installed a transmission drain plug on my 08 F150 - the Dorman type with the little o-ring around the drain plug itself. While the plug body itself is leak-free, the little drain plug has developed a drip. I've put teflon tape on the threads, and monkeyed with the torque, but a drip always develops. Problem seems to be the o-ring - it deforms under the slightest torque. Has anyone else had this problem? How did you solve it? If I can't solve this, I guess I'll be ordering the U-haul pan.
Leaking Transmission drain plug
- Thread starter Mulestang
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One option is to remove the Transmission Pan
and
have someone weld a hex nut to 'outside' of pan.
Then use a bolt/gasket as a drain plug.
By welding the nut to 'outside' of pan, you get more fluid to drain out, as compared to having any nut inside the pan.
That's what I did, and I also used a 'magnetic' drain plug.
and
have someone weld a hex nut to 'outside' of pan.
Then use a bolt/gasket as a drain plug.
By welding the nut to 'outside' of pan, you get more fluid to drain out, as compared to having any nut inside the pan.
That's what I did, and I also used a 'magnetic' drain plug.
Thanks, Larry. Unfortunately, I'm not in the poistion of being able to drop the pan and take it to a welder. It's my only set of wheels. If I can't get the little plug leak to stop, I'll get the U-haul pan that has the drain plug setup like an oil pan.
The problem is the o ring. O rings work best in a static compression environment not a turning one. The o ring cuts easily and is ruined, it will never stop leaking.
Go to HD or a hardware store and get a nylon flat washer (usually white) the same I.D.a pack of 10 should only be a few buck. Tighten firmly but don't over tighten.
Go to HD or a hardware store and get a nylon flat washer (usually white) the same I.D.a pack of 10 should only be a few buck. Tighten firmly but don't over tighten.
I used a similar drain plug kit (this one: http://www.amazon.com/80250-Automatic-Transmission-Universal-Drain/dp/B00029WR78 ) to install a transmission temp sensor. The nylon washers and the plug itself have been leak free over the several years that it's been installed. You might just swap out for this brand...cheaper than a new pan, and you've already got the hole...
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Yeah, I'd replace with a nylon flat or a crush washer. This can be messy but, there are techniques to doing this without losing much ATF.
You may have to pull the plug that's in there now, and hurry up and replace it quickly with another plug with a proper washer.
Hopefully without losing too much ATF...This is what I've done in the past. These things don't happen often so, have more ATF on hand.
Let us know how you made out!
CB
You may have to pull the plug that's in there now, and hurry up and replace it quickly with another plug with a proper washer.
Hopefully without losing too much ATF...This is what I've done in the past. These things don't happen often so, have more ATF on hand.
Let us know how you made out!
CB
Rubber can be done right in this situation, but I agree with Trav that an inexpensive o-ring will not work well. For example, the Cadillac Northstar engines have an engine drain plug with a rubber ring/gasket molded under the plug's hex head. It works well and I owned two of these engines, one with 160,000 miles when I sold it and one with about 80,000 miles when I sold it and neither one leaked or ever had to be replaced.
But use caution with cheaper nylon washers, too. I used one instead of the aluminum washer on my Honda's transmission drain bolt once and it dripped somewhat moderately for days later. It turns out that it broke during installation...twisted apart I guess...
I never was a fan of the aluminum washers "some call them crush washers" that are typical on Japanese brands, but I will say, I've never had one to leak. I re-use them all the time, too. If you don't find success with nylon, see if you can find an aluminum washer that will fit your drain plug (at Advance or AutoZone).
But use caution with cheaper nylon washers, too. I used one instead of the aluminum washer on my Honda's transmission drain bolt once and it dripped somewhat moderately for days later. It turns out that it broke during installation...twisted apart I guess...
I never was a fan of the aluminum washers "some call them crush washers" that are typical on Japanese brands, but I will say, I've never had one to leak. I re-use them all the time, too. If you don't find success with nylon, see if you can find an aluminum washer that will fit your drain plug (at Advance or AutoZone).
Originally Posted By: Astro14
I used a similar drain plug kit (this one: http://www.amazon.com/80250-Automatic-Transmission-Universal-Drain/dp/B00029WR78 ) to install a transmission temp sensor. The nylon washers and the plug itself have been leak free over the several years that it's been installed. You might just swap out for this brand...cheaper than a new pan, and you've already got the hole...
Was your plug brass or steel? In the link you posted, the free-standing example has brass, but the blister package has a steel one. Mine is steel, so I'm wondering if I can get the brass plug and ditch the o-ring.
I used a similar drain plug kit (this one: http://www.amazon.com/80250-Automatic-Transmission-Universal-Drain/dp/B00029WR78 ) to install a transmission temp sensor. The nylon washers and the plug itself have been leak free over the several years that it's been installed. You might just swap out for this brand...cheaper than a new pan, and you've already got the hole...
Was your plug brass or steel? In the link you posted, the free-standing example has brass, but the blister package has a steel one. Mine is steel, so I'm wondering if I can get the brass plug and ditch the o-ring.
The material doesn't matter it still needs a sealing ring of some sort.
Buy a cheap drain pan for 5 bucks with hand cleaner and a roll of towels at AZ and drain the fluid in the new pan and right into an empty gallon ATF jug or gallon water jug that has been thoroughly dried so you can put it back in.
Buy a cheap drain pan for 5 bucks with hand cleaner and a roll of towels at AZ and drain the fluid in the new pan and right into an empty gallon ATF jug or gallon water jug that has been thoroughly dried so you can put it back in.
Originally Posted By: Mulestang
Originally Posted By: Astro14
I used a similar drain plug kit (this one: http://www.amazon.com/80250-Automatic-Transmission-Universal-Drain/dp/B00029WR78 ) to install a transmission temp sensor. The nylon washers and the plug itself have been leak free over the several years that it's been installed. You might just swap out for this brand...cheaper than a new pan, and you've already got the hole...
Was your plug brass or steel? In the link you posted, the free-standing example has brass, but the blister package has a steel one. Mine is steel, so I'm wondering if I can get the brass plug and ditch the o-ring.
In my case, the plug was steel, but I used it to install a temp sensor, which was brass...so, with a single wrap of Teflon tape, I know that the brass seals up well.
Originally Posted By: Astro14
I used a similar drain plug kit (this one: http://www.amazon.com/80250-Automatic-Transmission-Universal-Drain/dp/B00029WR78 ) to install a transmission temp sensor. The nylon washers and the plug itself have been leak free over the several years that it's been installed. You might just swap out for this brand...cheaper than a new pan, and you've already got the hole...
Was your plug brass or steel? In the link you posted, the free-standing example has brass, but the blister package has a steel one. Mine is steel, so I'm wondering if I can get the brass plug and ditch the o-ring.
In my case, the plug was steel, but I used it to install a temp sensor, which was brass...so, with a single wrap of Teflon tape, I know that the brass seals up well.
Originally Posted By: Mulestang
I recently installed a transmission drain plug on my 08 F150 - the Dorman type with the little o-ring around the drain plug itself. While the plug body itself is leak-free, the little drain plug has developed a drip. I've put teflon tape on the threads, and monkeyed with the torque, but a drip always develops. Problem seems to be the o-ring - it deforms under the slightest torque. Has anyone else had this problem? How did you solve it? If I can't solve this, I guess I'll be ordering the U-haul pan.
I would get a more substantial O-ring. Teflon tape should only be used to seal NPT threads. Not plugs that use some other method (O-ring) to make the seal.
Doorman stuff is OK, but not top quality.
I recently installed a transmission drain plug on my 08 F150 - the Dorman type with the little o-ring around the drain plug itself. While the plug body itself is leak-free, the little drain plug has developed a drip. I've put teflon tape on the threads, and monkeyed with the torque, but a drip always develops. Problem seems to be the o-ring - it deforms under the slightest torque. Has anyone else had this problem? How did you solve it? If I can't solve this, I guess I'll be ordering the U-haul pan.
I would get a more substantial O-ring. Teflon tape should only be used to seal NPT threads. Not plugs that use some other method (O-ring) to make the seal.
Doorman stuff is OK, but not top quality.
Originally Posted By: Donald
Originally Posted By: Mulestang
I recently installed a transmission drain plug on my 08 F150 - the Dorman type with the little o-ring around the drain plug itself. While the plug body itself is leak-free, the little drain plug has developed a drip. I've put teflon tape on the threads, and monkeyed with the torque, but a drip always develops. Problem seems to be the o-ring - it deforms under the slightest torque. Has anyone else had this problem? How did you solve it? If I can't solve this, I guess I'll be ordering the U-haul pan.
I would get a more substantial O-ring. Teflon tape should only be used to seal NPT threads. Not plugs that use some other method (O-ring) to make the seal.
Doorman stuff is OK, but not top quality.
I was under the impression the Dorman's plug was NPT. Maybe not...
Originally Posted By: Mulestang
I recently installed a transmission drain plug on my 08 F150 - the Dorman type with the little o-ring around the drain plug itself. While the plug body itself is leak-free, the little drain plug has developed a drip. I've put teflon tape on the threads, and monkeyed with the torque, but a drip always develops. Problem seems to be the o-ring - it deforms under the slightest torque. Has anyone else had this problem? How did you solve it? If I can't solve this, I guess I'll be ordering the U-haul pan.
I would get a more substantial O-ring. Teflon tape should only be used to seal NPT threads. Not plugs that use some other method (O-ring) to make the seal.
Doorman stuff is OK, but not top quality.
I was under the impression the Dorman's plug was NPT. Maybe not...
Originally Posted By: Donald
Mulestang said:
I've used a number of the B&M-branded universal drain plugs and had no issue with them. I've got one on my DD and one on the xwife's car. They do caution you not to over-tighten the inside nut...25 ft/lbs max.
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The nut in the Dorman never bottoms out. It will destroy the o-ring and then contact the bolt body.
I have never had a problem with aluminum washers torqued to specs on Toyota and Honda vehicles. Our AA has discontinued stocking aluminum washer so I purchase them at the dealer. No use going into AZ because the people working there don't know squat.
Originally Posted By: Hokiefyd
Rubber can be done right in this situation, but I agree with Trav that an inexpensive o-ring will not work well. For example, the Cadillac Northstar engines have an engine drain plug with a rubber ring/gasket molded under the plug's hex head. It works well and I owned two of these engines, one with 160,000 miles when I sold it and one with about 80,000 miles when I sold it and neither one leaked or ever had to be replaced.
.
The GM drain plugs are great but its rubber captured inside a metal ring. Oil filters use rubber too but the ring is is also captured, it just cant spill over the side.
Rubber can be done right in this situation, but I agree with Trav that an inexpensive o-ring will not work well. For example, the Cadillac Northstar engines have an engine drain plug with a rubber ring/gasket molded under the plug's hex head. It works well and I owned two of these engines, one with 160,000 miles when I sold it and one with about 80,000 miles when I sold it and neither one leaked or ever had to be replaced.
.
The GM drain plugs are great but its rubber captured inside a metal ring. Oil filters use rubber too but the ring is is also captured, it just cant spill over the side.
I have never had good success with teflon tape on an oil drain plug or any type of lube plug. Together, the PTFE & oil seem to make the leak worst!
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