Oil Drain Plug

[Blue hedgehog]

most oil techs are just retards and don't understand that the <20lb torque requirement is more than enough to seal. They figure if they make it extra tight it won't leak.

They also probably heard about a drain plug that fell out and blew the engine. Of course that plug that fell out probably was barely finger tight.

When I worked at a dealership we had one of those tarts doing oil changes. If he didn't tighten the oil filter till it bottomed out it was the drain plug. Either he would almost strip the threads, or only screw it in finger tight. 3000 miles later the plug was still there and not leaking. I'm in no way saying to leave it loose but muscling it down isn't necessary.

 

[Z71]

I always recommend only tightening an oil pan drain plug snugly, not torquing it. There is no reason to torque it. This is especially important with aluminum oil pans, which have softer threads than the drain plug.

Torque values are typically specified for dry fasteners, but the oil drain plugs will be drenched with oil when tightened and torquing them to a dry specification will cause about twice as much preload in the threads and can cause thread stripping in aluminum pans.

When you torque a bolt, about 90% of the torque goes toward overcoming friction between the bolt head and the underlying metal and friction in threads. Only about 10% goes toward preloading the bolt. With a well lubricated bolt, this friction markedly decreases, and the same torque will cause much higher stress in threads. So do yourself a favor and tighten drain plugs snugly only.

 

[Italianjoe1]

They give torque specs on drain plugs. They are usually 14-18lbs, to account for just what you said, they are always lubricated lol

I can tighten them that tight with a 1/4" ratchet, yet I see guys using a full-size breaker bar to put in drain plugs. It's amazing.

 

[wr_guy]

They use a torx or an allen bolt because it sits flush and a normal bolt will hang down and may get ripped off by a manhole cover or other hazard.

 

[$ub$onic]

They use a torx or an allen bolt because it sits flush and a normal bolt will hang down and may get ripped off by a manhole cover or other hazard.

Not all sonics have the torx, some have a hex

 

[attrapereves]

Not all sonics have the torx, some have a hex

I think we established that the manual transmission has a Torx plug and the auto has a 10mm. Or at least that is the case with my cars.

 

[1980PontiacWagon]

They use a torx or an allen bolt because it sits flush and a normal bolt will hang down and may get ripped off by a manhole cover or other hazard.

If you rip the bolt head off of the oil drain plug on a manhole cover or other hazard you are very, very low or have much more to worry about replacing/fixing.

 

[Z71]

IMO 15mm is way too big for an oil drain plug. The 10mm keeps shops from over torquing the plug. Seems like many people don't realize it's just a drain plug and not a head bolt.

If you want a cheap source of quality o-rings I'd go with Mcmaster carr. You can probably get a bag of 10 or 50 neoprene o-rings from them for a good price.

A couple of my motorcycles havea 24 mm hex head oil drain plugs on all aluminum oil pans. That does not mean I will try to torque them to 100 ft-lbs.

 

[Glenn]

Hi Guys,

Australian Barina RS Hatch, 1.4L Turbo, Auto...Torx Head.

It appears that GM/Holden have gradually changed over from Hex to Torx...over the last three GM products I have owned over the last 6 years or so, I have noticed the transition ( at least here ).

Glenn

 

[nzasian88]

Hi Guys,

Australian Barina RS Hatch, 1.4L Turbo, Auto...Torx Head.

It appears that GM/Holden have gradually changed over from Hex to Torx...over the last three GM products I have owned over the last 6 years or so, I have noticed the transition ( at least here ).

Glenn

NZ Barina CD 1.6L Manual.. Torx Head.. I guess the GM Korea (Where the holdens are made) are all torx?