[455guy]

What parts go first? Gears then ring and pinion?

[79GP6.6L]

Add me to the list of people who shot the spider gears through the rear cover! Cracked the differential and chipped a few teeth off the pinion gear too...all at once! That was on the stock unit. I could have been upset, but instead I thought it was pretty funny and saw it as a chance to upgrade.

My gas tank was not harmed, though.

[455guy]

Hindsite is always 20/20 right ;o)????

[455guy]

I have a 400 5 speed so the torque wouldn't be anywhere near that of a 455..Mainly street but will tow as well as hit the track once in a while.I could do stronger spiders and axels for less then 300.00 and I already have the rear with 63 k miles original so I might as well use it. A bud said he'd sell me a 69 gto 12 bolt for 500 but I hear it's not fun to get it in and set up. As well as being wider and worrying about tire clearance..

[Bill Eveland]

The last one I took apart , the pinion lost every bit of gear on it. This was just in a stock s-10 Blazer 4wd. I think they got stuck in the snow.
Don't waste your money on the 7.5.
The 69 12 bolt is about 3" wider, if your buying axles anyway, go with the 12 bolt aand have the housing narrowed or a bolt in g-body 9" housing. If your buying axles anyway that would be a great time to get the Moser axle ends that use the ford big bearing ends and stock gm brakes. The backing plate will have to be opened up for the bigger bearing.
South side machine lift used to have lower control arms to mount the older 10/12 bolts into a G-body.
Another friend of mine did something similar to what Colin was talking and used a rearend from a 68-74ish Nova and welded the backets on the housing. The brackets are available from some of the stock car building websites.

[crossbreed455]

I have taken out posi, axles, gears, and the spider gears. I even had a TA cover on the rear. That was behind a 450 horse motor. I went to a 9" it has been in the car for 6 years not a problem with it. Do yourself a good thing and buy a 9 or a 12 and save money for the long road ahead.

mike m.

[79GP6.6L]

If I remember correctly there were two...this was about 10 years ago...During cruising I would sometimes hear a rattle from the rear, as if there was a rock or something inside one of the drums.

The second, it only did this two or three times, but from a stop I would get a clunk upon accelerating...if I had to guess I'd say it was caused by the pinion landing on a chipped/broken tooth of the ring gear. At the time I figured the parking brake wasn't releasing.

I've gained a lot of automotive knowledge and training since then, and I laugh that I never thought to pull the cover off the rear and check it out.

[455guy]

Yea, I'd like to have a 9" in there but I already have the 7.5 rear and don't have the $$ to upgrade. I'll be nice to it and only beat on it when needed !!What were the warning signs your rear was on the way out?

[455guy]

What parts go first? Gears then ring and pinion?

[455guy]

Anyone have a Southside mahine part number on the conversion corntrol arms? I've looked and find it.

[242177P]

Don't know for certain, but I heard that Southside went out of business?

[455guy]

What engine,car,trans,axel ratio and weight were involved in the ker-splosion??

[bmpmdf]

Spiders thru rear cover, punched hole in gas tank. Bad night street racing ! LOST HALF A TANK OF THE GOOD FUEL !!! UGH !!

[Fast 82]

I suggest you change to a 8.5 10 bolt from the Grand Nationals it will last behind a 455 the 7.5 will not last it will be just throwing money away "my oppinion". I have a 82 Grand Prix with a 455 and I switched to a 9" Ford from Moser with 31 spline axles. No Problems! The other thing with the 7.5 they have small axles. If you are looking to buy a Grand National Rear end give me a call I have a line on one.

[customizedcreations]

I ll second the blown up spider gear setup. I threw my gears out the back and through a fence at the track. Street tires , 2.41 gears and a stock 400 in a 78 GP. Ran a few 13's , put some stickier tires on the back , and bang. I installed a another 7.5 with a 2.73 posi, and went a whole year and then sold the car. Ran 12.50's no problems. Just let the tires spin a little and you ll be ok. If you hook up, thats when you have trouble.

[Fast 82]

Yeah the rear end that my buddy has is going for $850.

[455guy]

I've looked and CAN'T find it..

[455guy]

Sounds like most kersplosions are at launch on stickies. A 400 or even a high revving 350 would minimise the shock of the torque and save those poor spider gears. I think I'll get new spiders and have them cryo treated and see what happens. I'll let everyone know how it goes. This will be a 95% street 5% strip car so I think I'll be fine.. Famous last words???? Heheheh

[79GP6.6L]

Options? Well, you could always try this...
http://www.thirdgen.org/newdesign/te...nguprear.shtml

Here's one more regarding the amount of power a modified 10 bolt will hold up to.
http://www.ws6transam.org/10bolt.html

Don't mind the links, I also own an 89 Formula. They use 10 bolts as well, but with different mounting points. And don't get me wrong, I'm not defending the 10 bolt. I'm just posting this for those who are curious about its durability.

[Colin]

An 8.5 would most likely be plenty strong enough.