need help in determining why some people keep the small bolt pattern up front instead of large bolt pattern. My rear is 5 on 4 and ahalf with weld wheels want to get weld wheels for the front to match. Also do you have to use a short tail shaft tranny for the a body. I have a 340 and found a rebuilt 727 long tailshaft.Thanks

 

The automatics, either 904, or 727 are long shaft for an A, but the 904/ 727 ARE different length, so if you are swapping between the two, you'll need to deal with the driveshaft

If you have a console shifter, make sure the trans you get has the holes cast into the trans housing for the shifter shaft mount.

Who knows on brakes. I dropped a Ferd 9" in my rear, and have not converted the front, matter of time, arthritis, and weather. I junked out a 73 and 74 A for the front disc parts. Soon as I get time, mine will get updated.

Carryin' two spares is no fun.

 

I think you are wrong The 904/727 tail shaft length did Not change. The 727 is longer than the 904. The 4 speeds did have different tail shaft lengths for A & B body. To use something like the later Volare disks 4 1/2 bolt pattern You need to change the control arms and the spindle to get the larger ball joint to match the later spindle for the disk and the brake caliper with mount

 

If you can't find F-Body stuff at your yards around you look for a M-body they have the same front brake set up. They are more common now than an A or F body.

 

Most of the the time it is easier and more practical to upgrade the rear before they move to the front. You can get the large bolt pattern axles for a-bodies pretty easy now since several shops either shorten B/C-body shafts or make their own replacement shafts.

The change to large pattern on the front becomes a little more complex, but not hard to do. You need to either find all the uppper arms, spindles, ball joints, break calipers, and disc brake master cylinder off a '73 and up disc brake car, or you have to buy a "kit." With the salvage yards crushing more often now, you made find it difficult to find a donor vehicle that hasn't been stripped already. The kits are a little more pricey, but will provide you with a one-time stop and shop option.

Several rim manufacturers are actually starting to make the smaller bolt pattern an option (such as Coy's) which could encourage someone to maybe convert the rear back to the small pattern. I personally, like the idea of the large pattern for strength and more wheel options. Just a thought.

Oh, I have a "long shaft" 727 in my car now. Fit was perfect (just like the factory did it). I believe the short shaft 727 was a 4 wheel drive thing.

 

Here is a shot of the 727 installed and 7260 u-joint driveshaft installed.