My Ford Explorer has been leaking on both sides of the rear differential, where the axle inserts into the differential. I took it to my mechanic, who said that the axle seals needed replacing. He did the job at a cost of $100 labor and $50 for two seals, which were Ford OEM. Problem was, it still leaked as badly as ever. In fact, it seemed to leak even worse, but I assumed that I must be imagining that. After all, it had new seals, so surely it couldn't be worse.

I took it back to the mechanic and he basically just threw his hands up. He said the seals had been replaced, and if done properly, it shouldn't leak, and there must be something more serious wrong with my rear end. He didn't seem too determined to get to the root of my problem, but rather just kinda rambled around my questions.

I took the car to a new mechanic, who began by contacting Ford. They acknowleged that 2002-up Explorers had had problems with axle seals, but that once the original defective seals were replaced with the newly-designed ones, it had been solving the problem. (Ford should've done a recall on these, but that's another issue altogether.)

Today I took it in to have the new mechanic replace the seals once again. He did so, and told me this afternoon that the car originally came with "seal guards", and that these should have been removed when the replacement seals were installed. He said it's right there in the instructions from Ford. They hadn't been, so therefore the axles were unable to seat into the differential, leaving a 1/4" to 3/8" gap. So, I was right! They were leaking worse than before! The original mechanic (actually his employee) had failed to follow the instructions, so I wasted $150.

I haven't picked the car up yet, but assuming the leaking problem is fixed, I plan to let the original mechanic know (in a diplomatic manner) what had happened. I'm not angry - people make mistakes. But my question is this: Is it reasonable that I should expect a refund of my $150, or should I kiss it goodbye? It seems very unfair that I wasted $150 on a repair that did not work, simply because someone didn't follow the instructions.

If he refuses and makes excuses, should I drop it, or pursue legal means?