I build lots of rears in my little one man shop. Parts are expensive so you only want to do this once. Getting used parts is a crap shoot. Building a Dana from a truck can be done but it is time consuming and can be done wrong. I’ve got a Dana in the shop right now that was not set up properly but it was still working. I would hate to have bought it as a good unit then opened it up to have to rebuild it. I don’t like spending money twice. They are one tough rear end, though. I’ve had plenty of 8 3/4 that have not faired that well even with street use. The rear end you need is for a 71 up b body and is a little more difficult to find in any form but an oem Dana is kinda rare. But not in high demand like an ebody so they don’t bring the ebody price tag with it. HOWEVER, I just happen to have something that might interest you. It’s an original 72 b body Dana 60 that has not been modified. As a matter of fact, it has been completely restored. I got it in parts deal so I don’t have the big dollars in it that the original purchaser did. It has everything new, axles brakes, sure grip, 3.54 gears and even powder coated. It was built by DoctorDiff. It is a first class unit and ready to bolt in. If you are interested, PM me and we can talk.

I can't tell you what better suits your car, but I can share what it cost me to build a Dana.

Got one off of Craigslist that was pulled from an 83 F250. All in it was about $2600 with all new parts except the ring and pinion and included disc brakes.

Almost identical to my experience. Cut down Dana 60 from a truck, welded on car ends and used a spool and Dr. Diff axles. Under $1k total and ran identical to what the 8 3/4 did the week prior. I run 3.54's.

A lot will depend on how the car is used also. I can tell you this that I bracket raced a 340 Dart back in the late 70's and early 80's. It was a 4-speed car and ran low 12's with a best ever et of 11.94 @ 113. Now when I launch a 4-speed car the gas pedal goes to the floor when the clutch comes out. In 4 years of racing the Dart I broke at least three 8-3/4 rears. Tore all the teeth of the ring gear once. Broke the pinion teeth once and broke the carrier once. Now fast forward to today and I have my 63 Sport Fury with the 8-3/4 rear in a heavier car. But my 63 is a 727 auto car. Its run 10.70's and it has never broke the 8-3/4 in it. I only race it about twice a year but its been on the road and raced some since 2011. The stick shift driveline is much harder on the rear if you run the car hard since it shocks the drivetrain. With an auto street car and street tires that don't hook the 8-3/4 should hold up fine. But with stickies it will depend and with a stick car it will be even worse. Ron

The gear fails first, resulting in the broken cap. The pinion deflects.

Always?

If so, That means an upgraded Cap mod is essentially worthless?

Wonder if the OEM cap flexes at all, facilitating less then ideal R&P teeth loading, leading to their failure.

If somebody gives you an 8-3/4 for free, go with it. If you are going to have to spend money, it's a Mopar, it looks better with a Dana under it.

I couldn't get 3.91s for my S60 from Strange about 2 years ago. Talking with Strange and Dr. Diff, 3.91s are not available from most (or all?) gear manufacturers for the Dana 60 / S60. I heard that some 3.91s out there are not cut correctly and will at the very least exhibit excessive noise. I wanted to upgrade from a 3.73 8-3/4 in my e-body to a Dana and ended up settling for the 3.73s because I thought the 4.10s would be too steep. I rest well at night knowing the S60 can take anything I throw at it drag racing with a big block 4-speed.

8.75 will be fine. Better yet save some money and get a Furd 9"

I was given this today. If I could get a housing for $100 would it be a good build to spend the money on good content and run it on the street? Sure grip, 3.91 and disc brake conversion.

Inside

Starting with a clean sheet of paper I would go with a 9" with NO FORD PARTS at all. Get a strong nodular center section from Strange and a Daytona pinion support and you will be fine with 35 spline axles and 4 pinion clutch style differential unit.

Gus

[quote=fourgearsavoy]Starting with a clean sheet of paper I would go with a 9" with NO FORD PARTS at all. Get a strong nodular center section from Strange and a Daytona pinion support and you will be fine with 35 spline axles and 4 pinion clutch style differential unit.



This is what the guys running in the 3's run. Next time at a big meet, look and see if I made that up. Actually, you won't see a Dana in those pits, anywhere.

I went that way a long time ago and I am still glad I did. Well, something else to ponder.

I run a Dana but if I was in a class where frequent gear changes were required I would certainly run something different.

A Dana looks good under anything. Here’s my S60 3.73 gears and a Detroit Locker in my Dart. It’s behind a Passon 5 speed trans.

Dude how nice is that! There are several nice upgrades within the camera lens. Is all that necessary or did you do it just because you wanted too?

Thank you. It's probably not necessary. I mini tubbed and did a spring relocation. Decided on a fuel cell and cut the trunk out and formed a box to hold the cell. Disc brakes are not needed but I wanted them. I made the hard lines, and used off the shelf DOT Russell soft lines going to the calipers. The suspension is Bill's RMS Street Linx, an older setup I bought 10 years ago when I started working on the car. I didn't like the bolt on brackets on the axle, so I ordered a weld on version from him, just to clean it up. When I put a Dana under my other car, (68 Fastback) I'm gonna stick with leaf springs. Seems to make things less complicated. LOL