[Rustynuts]

Got an aftermarket gasket filter kit. Came with bolts, so I Figured I'd use them. Most of them torqued to spec just fine, but a couple seemed to yield early and one actually torqued off. What's the best way to fix this? Will one of those easy out bits work without destroying the housing/threads? Give up, drill out and re-thread to slightly larger bolt?

The bolt is right in a corner, which I assume is probably the worst spot. So far it's not leaking.

 

[Doug Huffman]

Torque To Yield fasteners are one time use only, and I doubt transmission pan SCREWS are supposed to yield. More likely the yield that you felt were threads pulling. I cannot guess what the root of your problem is.

In the spirit of "First Do No Harm," I would drop the pan to expose as much of the screw as possible and prevent damage to the pan. Then clamp vise-grips onto the exposed screw and wriggle tighten and loosen until the galled threads are cleared and unscrew.

 

[timarnold]

I am not sure of exactly where this particular screw is located, but I was able to use a longer M4 screw and put a nut on top of the transmission screw boss on the one I stripped out.

 

[Rustynuts]

Torque To Yield fasteners are one time use only, and I doubt transmission pan SCREWS are supposed to yield. More likely the yield that you felt were threads pulling. I cannot guess what the root of your problem is.

In the spirit of "First Do No Harm," I would drop the pan to expose as much of the screw as possible and prevent damage to the pan. Then clamp vise-grips onto the exposed screw and wriggle tighten and loosen until the galled threads are cleared and unscrew.

If the threads pulled, why would the bolt head shear off? Would have just stripped the threads the other way.

I never even hit the 7-ft lb torque on my wrench. I'm voting crappy quality bolts.

 

[tibbles stryker]

Respect for doing this job, I gave up as I couldn't determine which plug was for the fill on the zf transmission. The plug where everyone and zf manuals have pointed to is filled with a solid nylon bung? Did you have to remove this?

 

[dukedkt442]

You snapped a bolt head off on 7 ft lbs??? Even a wooden bolt can handle that.

My vote is a faulty torque wrench. I don't even use a torque wrench when doing transmission pans or valve covers any more.

Drop the pan again, try vice grips on the exposed threads.

 

[abscate]

Respect for doing this job, I gave up as I couldn't determine which plug was for the fill on the zf transmission. The plug where everyone and zf manuals have pointed to is filled with a solid nylon bung? Did you have to remove this?

The fill on my 2006 was on the opposite side of the trans than the Bentley reference.

It is a French transmission, after all.