Crap Tools

Mike McLeod · 2020-08-13T15:37:36+00:00

This morning I tried to undo the oil *filler* plug of my BMW's ZF 6-speed automatic gearbox so I could change the oil and filter. I managed to find an allen key that was an excellent fit (8mm) but the plug was so tight I had to resort to thumping the key with a club hammer in an attempt to loosen it. At first it seemed like the plug was loosening but it turned out it was only the key twisting! The plug remained resolutely in situ and the key now has about a 45 degree twist in it. Fortunately it doesn't seem to have chewed up the plug. So I have the following questions: Is it normal for keys to twist like that under heavy load? Is it normal for gearbox plugs to be so obstinate? What's the best approach to getting the plug out going forwards?

Aug 13, 2020 21 Replies

Rate this thread:

Cursitor Doom 5 years ago

More likely a reaction between the alloy of the gearbox and the steel of the plug. Not the least uncommon.

Vote

Cursitor Doom 5 years ago

As they should, if they're hardened steel. The fact that the key bent shows it's poor quality and the force of the hammer blows is being absorbed by it instead of the plug. You need to *shock* the plug into releasing which won't happen if they key is prone to bending. Get a better quality tool and try again.

Vote

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required