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Stripped drain plug threads

A cast aluminum pan and a power tool are a bad combination. The fix is threads stronger than the ones VW fitted.

Mk4 vehicles had an aluminum oil pan. VW used cast aluminum pans on these cars to muffle engine noise, which is a good thing. The problem happens when oil change techs overtighten the bolt, or try to install the plug with power tools.

It is important to understand that lube guys are not mechanics. They may be mechanically minded, but they lack the training and experience to do most technical labor operations, and the fact that drain plugs are frequently stripped by them is evidence of that.

Oh, I see you have been going to an oil change place.
Drilled oversize and tapping with the Helicoil tap. A perfect angle is required for the washer to seal.
Oversized threads, ready for the Helicoil to be drawn in.
Helicoil insert drawn into place.

Stronger than factory.

The dealership would sell you a new oil pan for hundreds. We replace those threads with something even stronger than factory: a Helicoil. Stainless threads that are permanent. It requires drilling a larger hole, using a special Helicoil tap to cut new oversized threads, then drawing a coil of stainless wire into them to create new, perfect threads that are harder than the aluminum and harder than even the steel drain bolt.

Attention to detail is vital to this job.

This is a machine operation, and the threads have to be cut at a perfect angle. If the angle is not perfect, the washer will not seal evenly on the flat shoulder around the threads. The threads do not seal the oil. The threads pull the bolt against the washer, making a perfect seal against the oil pan surface. Patience, attention and a steady hand are required to do this properly.

This work is $100.00 when done in addition to an oil change. So it is the oil change plus $100.00.

Drain plug weeping after a quick-lube visit?

Don’t let someone keep cranking on it. Every turn takes more of the pan with it. Call us and we will put permanent threads in it.

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