“Houston, we have a problem…”
We started detailing the undercarriage and removed the rear axle so it could be cleaned up, resealed, and modified for 5 lug wheels.
![Mustang body on stands The rear axle is removed for some refurbishing while the undercarriage gets some detailing](https://www.johnaustinmotorworks.com/wp-content/uploads/2021/01/Mustang-body-on-stands.jpg)
The rear axle is removed for some refurbishing while the undercarriage gets some detailing
The axle was caked with dirt and oil and after some scraping we learned why.
![Rear axle out The rear axle before refurbishing. Notice the dark, oily, caked on dirt](https://www.johnaustinmotorworks.com/wp-content/uploads/2021/01/Rear-axle-out.jpg)
The rear axle before refurbishing. Notice the dark, oily, caked-on dirt
Something catastrophic happened in its past. We're not sure what yet, but it resulted in a crack or hole in the top of the cast iron housing. This is a pretty tiny, light duty axle, adequate for use behind a 6 cylinder engine. Someone attempted a repair with a stick welder (we'd call it a booger weld). We turned it over to clean the bottom side and when uprighted again, found gear oil dripping out of the old repair.
![Old rear axle weld repair We scrape off a bunch of crud and find a boogery old weld repair underneath](https://www.johnaustinmotorworks.com/wp-content/uploads/2021/01/Old-rear-axle-weld-repair.jpg)
We scrape off a bunch of crud and find a boogery old weld repair underneath
Did someone blow this differential up? We'll have to dig deeper to find out.
![Old axle repair Old weld repair leaking oil](https://www.johnaustinmotorworks.com/wp-content/uploads/2021/01/Old-axle-repair.jpg)
Old weld repair leaking oil
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