Looking for info on 8-1/4 rear end

[keith88]

Hi I have a 69 Charger with a 8-1/4 rear but it seems to be hard to find info on these in this car. Even in the manuals it dose not list them being in a 69 but i have heard that they were put in some small block car . Dose any know any info on these like what interchangeable ,what spline  (27or 29)and so on. What year will the parts work . I also would like to know if you can make a none posi a posi and what gears are available for them. Any info would be welcome ..thanks .

[Alaskan_TA]

The TSB about the 'new' 8 1/4" rear end is 32 pages long. Look for TSB D69-3-1 in the menu at http://www.hamtramck-historical.com/1969-Dodge-TSB-Index.shtml

[keith88]

Thank you some awesome info in that on a lot of stuff   Dose anyone know if the years are interchangeable, Like will the inerds work from a newer car?

[John_Kunkel]

Here's some additional info, can't attest to the accuracy.

http://www.dippy.org/forum2/index.php?topic=75.0

http://www.drivetrainshop.com/Chrysler_8_25_s/81.htm

[keith88]

Still looking for info on parts like is an 8 1/4 the same all years or when i buy parts is there a certain years that i have to stick with.I plan on changing the ring and pinion to 3:55  can it be any year? and how about the rebuild kit is there a year on that or will any work ? dose anyone know the answers to these questions.

[Charger74SE]

Still looking for info on parts like is an 8 1/4 the same all years or when i buy parts is there a certain years that i have to stick with.I plan on changing the ring and pinion to 3:55  can it be any year? and how about the rebuild kit is there a year on that or will any work ? dose anyone know the answers to these questions.

Year One has them but when you call them, they need to physically check the shim size in the kit. It must have the 3 inch dia. set and not the smaller set because the smaller ones are for a 75 and up diff. They also need to make sure that it has bearing set 47 in it which goes on each side of the ring gear case. 68 to 74 model 8.25 diffs used a smaller ring gear case bearing. In 75 they went to bearing set 37 which is a slightly larger bearing. This is a Timken bearing set number. Timken Bearings are the original bearings that were used back then. Timken has a website that you can download their automotive bearing catalog that covers the older model vehicles. They also has a cross reference catalog that you can download.
As for the pinion outer front and inner rear bearing, those are still the same size.
If you find just the bearing set with no shims then go to www.arizonaparts.com. Click on the Parts List and scroll down to part numbers starting at 2931960 to 2931978. These are the 3 inch dia shims for that diff. I started with my original shim which was a .073 and ended up with a .069 shim to get the correct gear mesh pattern.
Its getting harder to find parts for these old diffs.

[fy469rtse]

Keith , simple way is just to pull it down
press bearings off , the serial part numbers are on them ,
take them into the parts shop with you  ,  will save you time getting the right parts the first time 

[keith88]

So far i have bought a set of 3.55 for it and im going to buy the master bearing rebuild kit from motive that should come with everything it will need for a  rebuild of 69-75 8 1/4 rear. The only thing it dose not have are the axle bearing that they can get me for about $40 extra.

[Charger74SE]

Don't forget to change the speedometer drive gear to compensate for the new gear ratio.

[keith88]

Did that last year matter of fact i believe ill be putting the old one back in from what i see it will need that one with this gear.