The rear differential on my truck is leaking oil pretty badly, but I’m scared to take it apart and fix the problem. It’s leaking out the front, so I assume it’s the pinion seal, but I’m not familiar with how differentials work or are put together, so I don’t know what’s involved with replacing the seal. My Ford repair manual has instructions, but they’re hard to follow (like these), and the diagrams show tons of tiny parts, so I’m afraid I won’t be able to keep track of everything once I tear it apart. The thing I’m worried about most is the cost. As far as I can tell, the only parts I need to replace are the pinion seal and the crush sleeve, which should easily come in at under $20. But if something unexpected happens (like if I break something), it could end up costing money (and time) that I don’t have.