I've jacked up my parisienne to take a look at the steady bearing job at hand and had a look at the differential. It has the correct casting number 3789812 and the sideways P for a canadian posi but get this...it's got two metal gear ratio tags on it! looking towards the back..A solid round tag indicating 336's at 11:00 and one at 9:00 with two side clipped indicating 411's. What the dickens . Obviously something is afoot here as well (referring to 2bbl vs 4bbl on the 283).I'll jack it up again spin the tires and see what I've got. I would have guessed 308's based on my cruise home......We shall see.
The old ones had the tags, a round piece under a bolt, they cut pieces out to designate the ratio. Id bet 336s if you werent Erving 4000 rpm on the way home. Check all the casting numbers on the car, it seemed pretty stock to me. My 63 has 308s and was originally a 283 2 barrel powerglide too.
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63 Parisienne sport coupe (The Big GTO), black, maroon interior, 409 4 speed; former owner of a 59 El Camino, 63 Corvette SWC, 62 Chev Bel Air SC. 1963- Pontiac top selling car in Canada
Mahone Bay, NS Still not old enough to need an automatic
'64 Parisienne CS "barn find" - last on the road in '86 ... Owner Protection Plan booklet, original paint, original near-mint aqua interior, original aqua GM floor mats, original 283, factory posi, and original rust.
These tags,Pontiacanada, are not related to the diff lube ones. They are as mentioned just plain round metal tags with various bits cut off/out to denote gear ratio.I wiil post a link to look at...not sure if I can make it "live" though lol. I'll see if I can get a pic of mine to show you. http://www.60impala.com/differentialcodes.htm
Ok, I've jacked er up and spun the wheels and counted revolutions at the yoke....just under 3.5 which verifies 336 gearing. Here are a couple if pics of my headscratcher dual tags.Sorry the pics are sideways..round tag is at 11oclock , snipped tag at 9oclock looking toward rear of car.