If u were 2 buy used gears what r a few things 2 check b4 doing so? I found a set of FRPP 3.73's online and lookn 2 c what they r worth with like 10k miles on them, or would I b better off getin new 1's?

 

I wouldnt buy a used ring and pinion unless I could physically touch and see them in person.

 

The only thing you can really check is the wear pattern and if there is anything major like a chip or crack. And like zig said, you'd have to have them in your hand to do that.

I've bought or traded for a couple used gear sets, but both were originally set up in the shop I worked at so I knew they were good and didn't whine.

A new FRPP set from Summit is 162 delivered and most of the used sets I see run around 100 to 125. Personally, I'd want the piece of mind of having a new set that I know didn't get set up wrong and now whines it *** off. And that's not enough of an incentive for me to bite on a questionable part. But that would bother me. If you can turn the radio up to cover the humming sound, then don't worry about it.

You can always head to a junkyard and yank a set out of an Explorer or an F series for just a few bucks. It may have some miles on it but most likely, Ford was the last one to fiddle with it and not somebody that didn't know what they were doing. That's how I got my last set of 4.10's and a posi 31 spline carrier for almost next to nothing.

 

That is kinda my way of thinking jameslf. I just don't know much about gears, so I wasn't 4 sure if they r 1 of those things that buying used could save some cash or not. I agree then buying new 1's is better just 4 the peace of mind

 

I put used gears into my v6 mustang and it was a known gamble. They looked perfect, so I just hoped they would turn out ok. The shop said becuase they were used, that they couldn't give me a warranty on the install. If I were to put gears in the GT, I'd buy new gears just for the peace of mind.

 

Keep patrolling eBay if you're tight on a budget. I got a 3.73 install kit (pinion bearings, carrier bearings, seals, crush sleeve, pinion nut, races, and ring and pinion) for $215 shipped, and new.