Well where do I buy new gears then if that's the case or a new differential and not the axles.

 

Any parts house brick and mortar or online,Summit,Jegs,eBay etc. etc. The parts are easy enough to buy but it's not as simple as just bolting them in,that job is best left to a pro.
You might want to watch both of these videos,it will give you a pretty good idea of what's involved.

If you don't have time check out the second video at 1.45 seconds in.

 

Thanks for the vids, I checked summit and didnt find gears for the rear end, love that site though

 

Let's say the gears in the differential are no good, how will I determine how loose to put the that yoke nut? Also I read when I was looking for a torque spec on that nut that one guy said he weighed 250lbs and he was "hanging" on the wrench and he said he never had any problems. So I don't know why this didnt happen to him.

 

Watch the video,he stopped at 24 lbs stating it was to be between 20 and 25 lbs.
I guess that guy was just lucky,I'd take his BS with a grain of salt.
Summit has tons of gear sets for your car in different ratios and makes.
https://www.summitracing.com/search/...20and%20pinion
That said, again you'd probably be in over your head trying to DIY.
There's plenty of shops in most places that specialize in this type of work,if I were you I'd either load the car on a trailer and take it somewhere to have the rear end rebuilt.
Unless maybe you have the money to upgrade to a 12 bolt or 9" Ford.
The other option is wrecking yard /craigslist part outs to buy a complete rear axle to swap in,this could potentially be less money and a fairly easy DIY project.

 

If he was "hanging" on the wrench, he was crushing the crush sleeve. Before I did anything, I would just pull the rear cover and have a peak. A new cover gasket is a couple dollars and if you use a clean pan and have the old bottles, you can save the gear oil...you did remember to put gear oil back in, right? Not being a ****, but I've seen it done because people get distracted doing something else.
Also check u-joint straps and caps.

I will say this, if you went a touch past, I don't believe that was the cause. If I remember right, pinion depth is determined by shims on the inner bearing. The spec you got was for the pinion bearing preload which is determined by the crush sleeve. A little bit is not going to crush the sleeve enough to throw things out of wack. It may have tightened the bearing preload up a smidge, but that is not nearly enough to burn the bearings up.

I know how this sounds, but I've had to change the pinion seal in the old Jeep with Dana 44A, which is also uses a crush sleeve, twice. Both times I zipped it off with the impact and zipped it back on (low setting) and despite that axle being run low on oil multiple occasions and being an aluminum housing (they were known for wiping bearings), 280k miles later and it still works fine.

Edit: Before I forget, there is usually a preload spec for new bearings and a spec for used bearings. Double check which one you did.

 

Can I buy a complete differential from summit? Withought the axles?

 

They are not a drop in unit so the answer is no.
The old cars like '55 Chevys had a drop in diff and could be swapped out completely assembled but not these.
You can buy all the parts but it has to be assembled in the housing,the axle tubes are attached.
First thing as I said and MKC said,pull the cover and find out what's going on in there.
Again probably the cheapest quickest fix if it's broken is buying a complete used rear axle,they can be had for a few hundred bucks and some elbow grease to install that pretty much any novice can do. But first let's see what's broken!

 

Good plan, was thinking if I need new gear was going to tow it to a shop and get them to rebuild the differential as it looks toi complex for a driveway job.

 

Messing with rear ends is nowhere near as easy as it looks. Its not supper complicated but it is very unforgiving as you can see by your attempt to replace the rear seal. One mistake or forgotten check can and you will end in a major failure/do over. I would suggest either buying an entire rear from a junk yard or buy a complete new bolt in rear. Let put it this way, even after being trained on how to rebuild a real the dealership I worked with had an experience mechanic over see me on my first couple rebuilds. This was not the case with automatic transmission or engine rebuild, I learned a lot form him that was not in the book.

Replacing gears means the whole rear needs to be setup.

Converting and old rear to a 4th gen requires welding and the know how to set up drive line angles.

You would want to get a rear form a 6 speed car since the gearing is different the only thing you have to watch for is getting a rear with or without traction control to match up your wiring.