Automatic Transmission - Drain Plug - Torque Spec?

The factory spec for the drain plug on the A750 transmission is 21 foot pounds.

For those who have done a drain and fill, you know just how puny the drain plug bolt is.

Has anyone here actually torqued the drain bolt to that spec? (21 foot pounds as measured by a torque wrench)

I can get it torqued to 15 foot pounds, but as soon as I go for 20, I swear it feels like I'm going to strip the threads on the bolt or the pan.

I'm thinking it comes with a crush washer from the factory and I'm just feeling the crushing of the washer, but I'd rather not have to buy a new pan this early in my ownership of my Taco.


*edit - The reason I'm asking and why I care is, during my last drain and fill, I torqued the drain bolt to 15 foot pounds and just recently found that it leaked a little. I want to snug it up as tight as possible without stripping the threads.

 

I never torque drain plug bolts. Like you, I examine the bolt, the washer and then apply some common sense. It's worked for many years.

I torque lugs(when at home) and would torque critical things like cyl. head bolts.

Update - missed the last part of your comment - my bad.

It's been my experience that many transmission pans bolts like brand new gaskets each and every time you drain/refill. Always change the drain plug gasket and overflow plug gasket on the A750E/A750F transmission fitted in 2nd Gen V6 Tacoma's. Go easy on the torque. If you see a small drip, slowly snug up the bolt head a bit more - easy does it. If you use a new gasket and the pan is OK, the leak will stop once you snug it just right. It's all done by feel.

Drain plug/overflow plug use same gasket - OEM part #

$8 35178-30010

35178-30010
Refill plug gasket - OEM part # 90301-15004
Transmission Pan Gasket - OEM part # 35168-60010

 

Just like Lester said.

Ditto.

 

Yep.
Replace drain plug gaskets on everything,ever time.

 

Awesome advice sir. Now to find someone selling those gaskets in a 10 pack for cheap..

 

I searched ebay before I did this - looked for the 2 gaskets. None available in a 10 pack or any sort of multi-pack. All sellers were offering single gaskets for prices higher than the dealer(most cases). I went to dealer, but had to special order. None were in stock. That tells me they never do transmission fluid changes or simply reuse the existing gasket. That's not a real problem for the refill gasket up above where you pour ATF into. The 2 pan gaskets(drain/overfill) down below should be changed.

Some good deals on ebay for Toyota WS ATF. Free delivery for some of them.

 

So a bit of an update on this topic. If you look around on the 4Runner forums, a lot of guys there have stripped the threads on their A750 trans oil pans.

To reiterate, the factory service manual states the torque spec to be around 20 lb ft, but this would be a DRY torque spec.

Since most of us are changing out the fluid, the fastener will probably be oiled so the torque spec needs to be reduced by 20%.

So, torque to 16 lb foot to avoid any issues.

 

Taken from torque spec guide for 750e
Drain plug 21 lb. Oil pan bolts 39. Refill bolt 29. Overflow 15.

 

Taken from torque spec guide for 750e
Drain plug 21 lb. Oil pan bolts 39. Refill bolt 29. Overflow 15.

 

I think there may be a typo here, the oil pan bolts should be torqued to 39 INCH POUNDS

 

I Don't torque pan plugs, I do it by hand, crush the new gasket, then a 1/4 more thats it, run and check for leaks.

The 2nd gen pans are known for stripping drain plugs, it will just free spin, but this is often JUST the plug, as it is weaker than the pan threads.

 

That's why I no longer let the dealer do my oil changes. Really think they use a impact gun to tighten the drain plug. It's not like that is a "stressed" bolt...it just keeps oil from draining out. Geeezzzze!

 

I always use a new crush washer and tighten until it crushes. Go slow with easy pressure and you can feel the washer crush.

 

When I did the tranny drain n fill, the washer crushed at around 13 ft lbs and I tightened it to about 15 ft lbs. no leak

 

I was referring to the post above that said the torque for the "Oil pan bolts 39" which is the (20) 10mm bolts that connect the transmission oil pan to the transmission. It should be 39 inch pounds. Or to feel