Technical 9 inch Ford question ???

I picked up an early Bronco 9 inch 3.50 trac loc for my 41 Ford pickup project.

It won't turn over completely, and I pulled the third member, and there is some
surface rust on both the pinion and ring gear. Not pitted really, and just on half
of the ring and pinion. The rest of the axle looks great, it just probably sat for a
long time.

Can the ring gear and pinion be cleaned up, or do I need a new gearset?

Thanks,
Rich

 

Get some naval jelly, and see if you can dissolve the rust, clean it up, and run it until it fails.

 

How long do you want to drive it?

 

You could take a brass wire brush or they make plastic brush that can be put on a drill. I'd think trying a steel brush but it would remove metal from the ring gear were as the brass or plastic brushes would only remove the rust.

 

Get a gallon of evaporust and let it do its work for a few hours. You will be amazed with the results, I was. You will need to degrease first of coarse.

 

I'm not sure how we're supposed to guess whether or not it will "clean up", without even seeing a picture...

It's been my experience that when gears get rusty like that, they usually "clean up" to where I look at how much metal is eaten away, and I don't want to use them.

 

Probably needs complete disassembly because you can't see all of the bearings. If there is pitting good luck.

 

If the R & P is rusty, what is the condition of the bearings ?

 

In my experience gears that have got rusty never last , you can clean them , wire brush , whatever ... may last for awhile but I wouldn't expect them to hold out for another 50k or anything

 

Disassemble....clean....inspect....if all good, reassemble, run

 

This is what we use to remove rust and mil scale. Its like jelly so you can brush it on and rinse with soap and water. The thicker and longer left on the better the results. It dose have its down falls the bare metal will flash rust so you gotta get it dry and covered by oil or primer as soon as possible. And the price $50 a gallon.

 

Watch this series of you tube videos of this guy inspecting and rebuilding a ford 9" rear and then you can decide what ya need to do yourself.
Rebuilding Rears- Part 1- Disassembly and Inspection - YouTube

 

If the ring & pinion are rusty, then I would imagine that the internal limited slip components such as, side gears and pinions, clutch plate, drive and driven plates, etc. are also just as rusty and would need disassembly for inspection, cleaning or replacement also.

Limited slip hard parts, side gears, pinions $150
New limited slip clutch and drive plates $90
New bearings $90
Ring & pinion gears $150-$200 minimum

There's all kind of rust removal processes, I'm somewhat cheap on stuff like that. I soak all of my rusty parts in a gallon of White Vinegar for 24 hrs then hit it with a knotted wire wheel on a 4" grinder, makes the metal look like brand new! Works really good on old rusty tools. The rust pits will still be there, but the rust will be gone.