Hey, this is my first post - I've been on Hot Rod a lot for the Power Tour.  

Car: 66 GT Fastback
Rear End: 8 in open 3.00

I think the bearings are going out, but want another opinion.  The car was restored in '74 by my dad.  At that time, the rearend was not rebuilt as it was fine.  He also has never had the bearings replaced that he can remember - just checked the fluid levels.  This spring the rear started making some noise.  I put the car up on jackstands and ran it - the wheels don't wobble or anything.  Free spinning them by hand is 'hard'.  I had it on the road the other day and in the city (under 35) it drives fine, other than some noise.  On the highway, the car was really jerky, ie constantly correcting the steering wheel.  This was similar to when we put new leafs in and the axle was seated slightly crooked.  My thought is that the bearings are wearing and the rear tire speed is changing ever so slightly causing the car to want to rotate?

Not really sure how to descibe it, but hope that makes sense.  If this is bearings, I know that I need new bearings, a press, what else?  Is there anything else?  Can I do this without having to remove the drums completely?

Any info would be great!  

To get to the axle bearings, jack the car up, remove the rear wheel, remove the drum and using a socket, undo the 4 nuts you can reach through the hole in the axle flange.  (You have to rotate the axle to line the hole up with each one.)  You can leave the brakes in place.  Pull the axle out, keeping it straight and supported as much as possible.  The bearing is pressed on the axle.  Replace the seals at the end of the axle housing.  After many years they are probably shot and they don't take kindly to having the axles removed.  My experiences with 8" rear ends is that these bearings are the first to wear out and make noise and the pinion bearing is next.  Mine were many years and way over 100K miles before anything happened.  I am a big fan of 8" rear ends.  

Thanks for the instructions.  Seems straight forward enough to me.  Question - should I replace both sides?  This car has 40K on it since restored, but before that the mileage is unknown.  I've heard of these running a couple hundred if the fluid levels are kept good.  I checked the fluid level and it seems fine.  Normally, doesn't the rear leak when the pinion starts to go?  

Another question - I have the four bolts off, but the axle doesn't seem to move - do I just need to pull 'harder'.  Sorry for the dumb questions - never done this before....  

Yes, replace the bearings on both sides.  Try jiggling the axle while pulling on it.  When you get it out, take the axle and the new bearing to a machine shop to have them press the old one off and the new one on.  

The pinion bearing that wears out and makes noise is toward the rear of the car (supports the rear end of the pinion shaft) and will not result in a leak.  Don't worry about it until you have replaced the axle bearings (which are probably causing your noise) and the noise is still there.  My pinion bearing failure wasn't obvious.  After I got the "chunk" out of the rear end housing I did notice that the rollers in the pinion bearing would roll and stop, roll and stop, as I turned the input.  The machine shop that serviced it confirmed my suspicions.  

Thanks for the info guys.  Another question - can I drain the fluid out with out pulling the third member?  

Buy and use a suction gun.  It looks like a grease gun but works in reverse.  Make sure it will pick up thick oil.  Refill it with synthetic lube.  It costs more but is better.  

Got it put back together last night, the bearings roll much easier.  I have to put fluid in tonight and then hopefully ready for the Car Craft Nationals.  

Which weight do you recommend?  75/90 should be good enough, right?  

That is what I use.  Others may have a different opinion.  I hope your noises and problems are gone.  Good job!  

thanks for the help!  it's quiet and rolls real nice now. btw, they were original - the FOMOCO stamp and PN was on the seals.  amazing that they lasted 42 years and ???? miles.