What do I use for a rear end for my car??

[green69rt]

While my car is off at the paint shop I have several things to work on so they will be ready when it gets back.  One thing is the rear end.

The pics below show the unit as it exist today.  A 489 case open rear with 2.76 gears (I think) So....

First, the car... 1969 Charger RT clone.  Either a stroked 400 or a slightly warmed over 440.  Probably in the 400-499 HP range.  Street driven a lot (at least that is my intention.)

I have a mechanic that I have a lot of confidence in so he will do the rear rebuild.

I started my search by looking on the DR Diff site.   It has a nice package on this page

http://www.doctordiff.com/8-3-4-489-case-third-member.html        but requires some option choices.  So, I have a couple of questions.

First question - The Dr Diff site requires that I choose between a clutch type and a True Trac unit (for an extra $175.)  Why would I spend the extra money?   

Second question - then it asks about the yoke..7290 or 1350.  I have no idea what this means.  ANy comments would help.

[cdr]

get the clutch sure grip

it should have a 7290 u joint,but could have a 7260

[cdr]

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CDEQ0gIoADAA&url=http%3A%2F%2Fwww.driveshaftspecialist.com%2FHTML%2520measure%2FUJ%2520ID%2520Guide.html&ei=MGE6UteUFcWR2wXRkoHYDg&usg=AFQjCNGMckPOzE7N2JuXjtWNDZlPSY9A7g&bvm=bv.52288139,d.b2I


this should help

[green69rt]

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CDEQ0gIoADAA&url=http%3A%2F%2Fwww.driveshaftspecialist.com%2FHTML%2520measure%2FUJ%2520ID%2520Guide.html&ei=MGE6UteUFcWR2wXRkoHYDg&usg=AFQjCNGMckPOzE7N2JuXjtWNDZlPSY9A7g&bvm=bv.52288139,d.b2I


this should help

Well, it might be clear to you, Charlie but it's a mystery to me.  Maybe you should come take a look.

[cdr]

i can do that. 

[green69rt]

i can do that.  

Just say when. Lunch is on me... TANSTAAFL!!

[cdr]

get the 7290 yoke.

[green69rt]

get the 7290 yoke.

That will probably work as the my drive shaft will need a complete rebuild.  It is a rusty hulk!!  So I can choose my own parts.

[fy469rtse]

Shit Mitch , if I new you offering lunch I would have answered you earlier, you can reuse a lot of that, definitely true trac , or if you can get your hands on it a track lock cica 68?'s, use the casting numbers , last three digits 489,  I use dts for bits or more recently the diff man ,
Mitch ask for the kit that eliminates the crush sleeve in your 489 centre, there's a kit solid pinion spacer, more work for them to set pinion depth with shims , but a lot stronger. 7290 is for the universal size big block that 1350 is ford, and won't match differential yokes on shaft or slip yoke,
Ask about or google search on the traclock , great unit, pulled units apart that have never been serviced , could through thence back together with new bearings and gaskets,
Recommend putting spinning your axles in a lath if you can, will show up any buckles in axle or mating surface for rims to bolt up to, if the later you press straight and then skim them in the lath, eliminate potential vibrations later
Use the timken axle bearings, and don't let them talk you into the green type bearings, again easier for them with less set up work and eliminates axle end play adjustments, factory setup the best, stick with it