I've done and read a good dozen different ways to get the fill plug loose including heat, a 10 pound hammer, a cheater bar and my favorite, using a jack with a small cup (Sears sells them for $100) and putting the other end of the wrench in the cup and jacking it up while you have the car on stands.

Today I didn't have the small jack but I did have a ratchet strap that I wrapped around the engine crossmember and the wrench. A literal piece of cake.

 

Great idea!

I'm about to do my differential and will try that if it's as tight as my 280s was. Seems like those are female type plugs and I used a half inch pull handle or ratchet.

That's one helluva oil pan you got on there!

Edited June 7, 20177 yr by siteunseen

Sometimes ther is slop in the square. I've used a blade screwdriver to take up the slop. Worked great. 

Might I suggest that if there is any slop in the fill plug (17mm) that you could file it down to 16mm and be assured of a tight fit without worrying about adding another tool to make this work. I mean how many times do you use your 16mm wrench anyway?

Or...

Nooo. Likely to damage the plug and now you're filing it down to 16mm. I have a better all around solution and I'll post it later tonight.

It's really for folks like me who change tranny oil 4-6 times a years.

There's no pressure built up in the tranny is there? A rubber freeze plug? a bolt? or just tap a 16 point socket on the square plug.  Anxious to hear your solution and why in the name of god do you change it 4 to 6 times a year?  I'm guessing you are a racer? That would explain the huge oil pan I guess.

Rock on!

Yes, I race a 240 and that is the small oil pan (6 qt) as opposed to the large (8+) pan. Add in filter, lines. Accumsump, cooler and you have 12 to 16 qts. invested.

As to the idea, here's the prototype that I used to verify that it works. The version going in the race car will be longer, have a connection point to the body and be lighter in weight. Think auto tranny dip stick with a threaded cap that can be removed via a socket.

 

I'm pretty sure that I got a 1985 300ZX 5 speed for $20 because the PO couldn't get the drain plug out.  I used the gears and back half as a 71C with a ZX 5 speed front/bellhousing swap, then tried to get the plug out of the left over front case using all kinds of crazy techniques; torch, solvents, breaker bars, etc.  Ended up drilling a hole in it just to show it that I could use it if I really wanted to.

It's available if somebody needs a 1985 300ZX front case/bellhousing.

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