rear end swap

[bronco9588]

I have a 73 charger and I want to do a 8.75 to dana 60 swap. I am considering dropping off my 8.75 to the mechanic to match my dimensions. I am looking at 3.73 gears, tremec .68 OD and a powertrax limited slip unit.

I would like to put 4 wheel disk breaks in for safety. And figured this could be done while the rear end was being worked on.

I was just wondering what people thought of 3.73, dana 60, tremec trannys, powertrax.

I have yet to find a tech article on a rear end disk conversion, and don't know where to start to find rear disk breaks.

Thanks.

[peg leg]

Can be found at many suppliers. Best bet is to pick up a copy of Mopar Muscle magazine and peruse the ads. SSB, Inline Tube and more are listed there.
Be careful locating the spring perches. I believe the axle tube diameter on the sixty is larger, and this will effect the perch location, for proper diff. angle. The proper way to locate them is to mount the axle without the perches, and adjust axle position with an inclinometer.
The Mopar books seem to like 3-6 degrees down angle, as I recall.
I have a Dana Powerlock in my 8 3/4, and like it a lot.

[bronco9588]

so you are saying that the spring mounts should be the same angle on the dana 60 as it would have been on 8.75. However, the diameter is larger, and therefore if you try to match the placement, you will be off in angle. I just want the angle to match the drive shaft mount.

[Ray Bell]

Rear disc brakes for 'safety'?

I often wonder about these comments. In many ways, drums are better than discs on the rear.

For a start, your e-brake will generally work better. But the main point is that rear brakes only carry about 20% of the braking load in most cars, with 80% on the front... they are underworked.

Discs only come into their own in constant heavy braking situations, where fade becomes a problem with drums. Of course, they also don't need adjusting, but a decent set of rear drums won't have to be touched very often either... even assuming there's no self-adjusters.

[Stoga]

I've often wished that my 04 Ram had rear drums, especially after I replaced both rear disk/e-brake drum assemblies and a caliper last year. My wallet still aches in remembrance! Now if you're doing a LOT of high speed performance driving or just want the more custom look of disks for show, then go for it.
But, I agree with Ray, if you don't have a good reason for replacing them, leave the drums, they'll do just fine on the rear.

[peg leg]

The larger the diameter, the lower the perches are from centerline. That is why you must use an inclinometer to set the angle correctly.

[bronco9588]

If you go with the dana 60, what is the diameter difference between the 8.75 and the dana? (I just mesured mine with a tape mesure and it looks like it is 3 inches in diameter) Wouldnt you need larger u bolt and the plate the shock absorber attaches to?

[ehostler]

The 8.75 and Dana 60 rear use the same diameter tube. I've done a few 8.75 to dana swaps and never had to replace the perches, shock mounts, etc.

[bronco9588]

Originally Posted by peg leg

Be careful locating the spring perches. I believe the axle tube diameter on the sixty is larger, and this will effect the perch location, for proper diff. angle. The proper way to locate them is to mount the axle without the perches, and adjust axle position with an inclinometer.
The Mopar books seem to like 3-6 degrees down angle, as I recall.
I have a Dana Powerlock in my 8 3/4, and like it a lot.

did you have to adjust the perch location?

[ehostler]

No, the perches were already at the proper location and angle. That's because the Dana that I used came from a B-Body.

[bronco9588]

since the axle tube diameters are the same, than I should be able to replicate the exact demisions on the 8 3/4 wrt the perch location. (Unless the drive input is different on the dana that would warrant a change in the angle of the drive input?)