Oil and Transmission Fluid change

[hi8ha]

Would like to know why is the OIL and Transmission fluid change recommended to be done at working temperature?

What is the difference in changing them cold?

The torque for the Oil drain plug in the DIY topic shows 37 Ft-Lb, for the filter shows 19 Ft-Lb. My torque wrench is in NM's. What is the equivalent?

Also. isn't 37 Ft a little too much. The LN Engineering plug ask for 19 Ft.

Edited March 30, 2013 by hi8ha

[logray]

Cold oil/fluid doesn't flow very well and can leave deposits behind. Try draining your gear oil when it is 38F. It will take days to drain out.

The reason why we warm it up is so it drains faster, easier, more completely, and with less sludge behind.

A good ft. lb to NM calculator:

http://onlineconversion.com/torque.htm

If you use the LNE BIgfoot drain plug, use the specification on this page (19ft lb): http://www.lnengineering.com/drainplug.html

If you use the stock aluminum plug, use the specification on the workshop manual/owners manual.

The two drain plugs have different hardness and thus require different application of torque to provide a good seal. The Bigfoot plug can have a tendancy to strip the threads on the sump plate because the metal is much harder than the stock cast piece.

[hi8ha]

Everything makes sense.

Thanks.

[JasonStern]

If you use the LNE BIgfoot drain plug, use the specification on this page (19ft lb): http://www.lnengineering.com/drainplug.html

If you use the stock aluminum plug, use the specification on the workshop manual/owners manual.

The two drain plugs have different hardness and thus require different application of torque to provide a good seal. The Bigfoot plug can have a tendancy to strip the threads on the sump plate because the metal is much harder than the stock cast piece.

Actually, the LN engineering drain plug is made of a weaker material than the OEM drain plug, hence the torque specs being roughly half. If you forget this and torque the bolt according to the factory shop manual, the bottom part of the drain plug will snap off, and you will immediately be in a state of panic as you wonder how you can possibly get half of a drain plug out of an oil pan once it has been torqued beyond its limits. If you're lucky, and odds are you will be, you can still get the plug out by applying upward pressure on the hex socket. You'll then have to either track down the OEM drain plug or not drive your car until a replacement arrives. On the plus side, since keeping the OEM drain plug worked out, you can now justify hoarding all kinds of parts you will never use, like that gas cap that might be leaking, or maybe you just forgot to turn until it clicked one time...

[logray]

Actually, the LN engineering drain plug is made of a weaker material than the OEM drain plug, hence the torque specs being roughly half.

Actually, you have that backwards.The LNE bigfoot drain plug is "machined" out of a billet piece of high strength hard anodized aluminum. It is MUCH harder than the standard OE stock drain plug. If you've ever held the two in your hands you can feel the difference.If you apply more torque to the higher strength metal plug against the sump, it is going to have a tendancy to damage threads in the plate or plug. if you apply less torque to the lower strength OE plug, it might not seal as well.

...you will immediately be in a state of panic as you wonder how you can possibly get half of a drain plug out of an oil pan once it has been torqued beyond its limits

If I managed to get myself in this position and unable to remove the sump plug, I think I would simply remove the sump plate and take it to my local machine shop.

You'll then have to track down the OEM drain plug

I think I would replace it with another LNE drain plug, however in the case you mentioned above, I would more likely be replacing my sump plate.

Edited April 11, 2013 by logray

[JasonStern]

Actually, the LN engineering drain plug is made of a weaker material than the OEM drain plug, hence the torque specs being roughly half.

Actually, you have that backwards.The LNE bigfoot drain plug is "machined" out of a billet piece of high strength hard anodized aluminum. It is MUCH harder than the standard OE stock drain plug. If you've ever held the two in your hands you can feel the difference.If you apply more torque to the higher strength metal plug against the sump, it is going to have a tendancy to damage threads in the plate or plug. if you apply less torque to the lower strength OE plug, it might not seal as well.

Not trying to spread false information, so I apologize if I am incorrect. Judging by the metal not deteriorating around where the hex socket enters the drain plug, the metal itself likely is stronger than the OEM plug, However, judging by the drain plug splitting in half, I am inclined to believe that the density of the casting is not as uniform, which may actually be intentional.

I'm not trying to badmouth LN Engineering here. They stated the torque specs, and I simply forgot that their product required different torque specs and did what most people would do in that situation - ensure the factory torque specs were used.

...you will immediately be in a state of panic as you wonder how you can possibly get half of a drain plug out of an oil pan once it has been torqued beyond its limits

If I managed to get myself in this position and unable to remove the sump plug, I think I would simply remove the sump plate and take it to my local machine shop.

And luckily for me that wasn't the case. The oil drain plug simply cracked in half and I was able to get the half that did not break off out with the hex socket. The state of panic was momentary, and mostly stated for the sake of story telling. Had I repeatedly read that the torque specs were different, something likely would have resonated in my head and I would have lessened the torque I applied, hence why I took the time to make a post reiterating that.

You'll then have to track down the OEM drain plug

I think I would replace it with another LNE drain plug, however in the case you mentioned above, I would more likely be replacing my sump plate.

The sump plate is fine. This actually happened on my 986 and not my 996, which I might add still runs an LN Engineering magnetic drain plug. LN likely engineered the plug to fail this way to avoid the negative reputation of having to potentially replace an expensive Porsche sump plate to protect a relatively inexpensive oil plug bolt, in which case, thank you.