Hey guys, I'm kind of new to this but anyway. I was told recently by my mechanic(my dad) that the rear end is going out in the Colony Park. I don't know much about rear ends or what really to do. All I know is that on the build sheet is says high ratio axle, and a 390 if it matters any. I'm not sure if its a 9inch and 8inch or even how to tell. My dads been busy working on my moms car to really guide me in anyway or to help. I'm not sure what rear ends would fit if I were to swap them or if I should try to get a shop in town to rebuild it. Any and all opinions and suggestions are welcomed as I am lost as what I should do.
Here's an axle chart for you. http://www.coloradok5.com/axleguide.shtml And another one: http://www.nationwideparts.com/differentials.htm A Ford Axle Tag Decoder: http://www.hotrodders.com/forum/ford-rearend-axle-tag-id-codes-posted-130274.html Any of the bigger Mercurys from about 1969 to 1972 would work. If you change the ratio, you'll also need to change the speedometer gear: http://www.steeda.com/products/speedometer_recalibration_gears.php Here's a Speed calculator for the speedo gear: http://www.superstallions.com/tech/calc/est_mph_ratio.aspx Clearer explanation of speedo and rearend gears: http://www.ffcobra.com/FAQ/speedo.html I'd check out the model groupings for your 1970 CP. They're shown here as from 1969 to '72 as well: http://en.wikipedia.org/wiki/Mercury_Colony_Park Then shop around for set. A Hollander manual might help narrow your search. Don't do this without some experienced help around, expecially if you're changing just the gears. Alignment is a precision job. If you got a similar axle, you'd still need some buddies to get it in and out. AND some BIG wrenches! Good luck.
Its either a 9" ford or a Ford WER axle it Has a cover on the back end that had 10 or so bolts going around it. My 70 Country squire has a WER axle and i will be swapping it to a 9" this spring. I'll assume since its a 390 car it has a 9" (stronger axle) and they rearely go bad ?
Well the high pitch whine and the fact that once we got it up on the lift that it had no rear end fluid in it. :-( we put some in but the pinion seal is all but gone and leaked out. Apparently the kid I bought it from got it from his grand dads field in Colorado.
well that will do it When you added fluid did you notice a cover on the back of it bolted on covering the gears?? Or do you have a pic? Then we can narrow it down, either way your going to need a rebuild or swap another one in.. Or atleast swap in a center section if its a 9"
This isn't very hard to do, but they are heavy so be prepared. A good set of ramps or jackstands, and a few hand tools will do it. A good dry place to work on helps too. There should be a tag on the driver's door with a bunch of numbers on it, one of those numbers will give you a code for axle ratio, and whether or not it has limited slip rear end. If you can post a photo, I can try to help with that. You probably want to stay with about the same ratio. You also need to know the spline count. Typically they are either 28 or 31 splines. I am more familiar with truck 9" rears. I believe trucks were 28 splines until 1973 in most cases. 73 they went to 31 splines. I am not sure about wagons. You could probably find that info on the net, or pull an axle and count the number of splines. It isn't very hard to swap in a new center section, lots of Ford guys do it to swap gears fast. They are heavy though, and good chance when you reinstall it you might mash a couple fingers trying to line up all the studs to get it on. At least I usually do. FYI, lots of people in my area call these pumpkins. In case you are on craigslist looking for one. A limited slip would be pricey if the seller is aware it has one. Good donors can be found at wrecking yards. A similiar wagon would be great if you can find one. If not, and you can determine what gear ratio, I'm guessing a wagon might have a 3.25 rear. That would be great, it's a popular ratio in most mid 60's to mid 70's half ton V8 trucks. Limited slips are pricey. If you gears are below 3.00, you might be able to buy a cheap center section of a Mustang guy. They usually want to get rid of those for something in the 3.50+ range for better acceleration.
