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Hi -

After researching and reading, I'm a bit confused over what rear end would be on a 1969 GTO from the factory. From what I understand, it's a 10 bolt Safe T Track (posi) rear, but I've read a few things that seem to indicate that there were some that do not have the pontiac version of posi - but rather an open gear.

Can anyone fill me in on what exactly was shipped with these cars and if there were options, how can I tell what's inside without taking it apart? Housing numbers, etc?

Thanks for any info!
 

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The standard rearend for a base 400 350 horse 3 spd car, the base '69 GTO, was a gray iron housing Pontiac 8.2 10 bolt with 3.55 gears. The axles will be the std duty Pontiac 8.2 axles with RW507 sealed axle bearings. I've yet to find an original example of a late '69 model Pontiac A-body with tapered bearing axles & ive been pulling original axles, & differential parts for near 3 decades. Late '69 Firebird production, yes, they had tapered axle bearing axles.

Safe-T-Track was optional. With 3.55's, the Safe-T-Track (posi) carrier would have been a 4 pinion unit, & the center hsg will be nodular iron with a Julian date code, not the common gray iron center hsg. The gray iron center hsgs did not provide enough pinion support with smaller (less tooth) pinion gear ring & pinion sets. Pontiac went to the nodular iron center hsg in its lower ratio Safe-t-track & HD Safe -T-Track PONTIAC 8.2 rears, that began with '67 models. That tactic worked well in several applications, but was deemed inadequate as engine torque levels reached near 500 ft lbs.
 

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Can anyone fill me in on what exactly was shipped with these cars and if there were options, how can I tell what's inside without taking it apart? Housing numbers, etc?

Thanks for any info!
Here are the axle codes for 69, the code should be stamped on the axle tube and listed on your PHS report;

 

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