I need advice,

I took my truck in for a rear diff leak and the mechanic stated he couldn't remove pinion gear because it was had welded itself. He tried everything but did not want to damage the bearings inside the diff by heating it up.

I recently had the rear u joint replaced and it was really hard to get off. They had to use an air chisel.

He told me not to worry about it and bring it back in 500 miles. I am always getting oil changes at 3000 miles, so what should I do?

He ended up changing the leaky seals near the wheels, I'm new to the area and want to to believe this guy, I just don't want to get a lock up and kill me and 40 other people.

 

Find another mechanic.

Some Liquid Wrench and a little time would probably have solved the difficulty of removing the pinion shaft nut.
Whoever it is that will do the work to replace the pinion shaft seal had better be tuned into the method to adjust pinion bearing preload or your in for a noisy differential gearset.....or worse, a burned-up set of pinion shaft bearings. A new crushable spacer and shaft nut are required when the pinion seal is replaced....I will assume your mechanic knows this.

...that air chisel is a very efficient way to bung up roller bearings.

My experience with the U-joint fasteners is this: Ford uses thread locker. I used a torch with a pin-point flame to warm up the bolts and soften the locker material. The flame was directed carefully to the bolt heads to avoid overheating any of the seals in the differential or U-joint.

 

Thank You for your reply. To their credit, I was wanting the truck back same day, so they were working on it pretty fast. So far there is no visible or audible problems. I guess I will wait and see. Would you put new bearings in it or get a whole new rear end?

 

How much did they charge you for not fixing it? I would find a different mechanic and get it fixed.

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