[Speargun]

As I get closer to completing my car I'm trying to think ahead and identify any issues that may pop up. One of them has to do with the rear end in the car.

I have a Dana 60 5 lug under the car. It has a 3.54 gear & locker, but it's a 5 x 5.5" lug pattern and it's about (iirc) 2" wider than stock. If I keep this rear end, I'll at least need to re-drill or replace the axles to the GM pattern so finding rims won't be such a PITA. The offset shouldn't be too much of an issue, but it is something to contend with.
I don't know how hard it is to find brake, or other repair/rebuild, parts as well.

My other options are to find a 9" or 12 bolt that fits the car locally, doubtful, or buy a new one for way more than I want to spend right now.

Some people say the Dana 60 is the best thing since sliced bread and others say that a decent 9" or 12 bolt is better.

What say the hive?

[i82much]

Dana is the strongest. Ford is the way to go, almost as strong and WAY easier to swap gears - you just get another center section. 12 bolt is fine if you have one or can get one cheap, but no real reason to pick a 12 bolt over a Dana 60 or 9".

[Speargun]

A buddy just told me that a Ford explorer rear end (8.8?) is a common swap. They come with a 3.73 posi and only need the spring perch changed.

Anyone done this?
Will an 8.8 hold up under 600-700hp?

[68azbird]

Why waste money
You can have that rear shortened and new axels cut and drilled for less than 1/4 the price of starting from scratch.

[JLMounce]

Yeah if you already have the Dana 60, I'd stick with it since it's a good rear-end. Just get the mounting flanges changed over. Personally I'd have the rear end shortened to the stock length because it makes finding off the shelf wheels much easier.

If you're planning on doing a custom wheel anyway, I wouldn't spend the money to have the axle shortened, just built the wheels to the correct offset.

[tom s]

Good but heavy compared to the others.Tom

[Chicagogoat]

As Tom S said, the Dana is the heaviest weight wise and heaviest gears with that massive 9.75" ring gear! The 12 bolt is a lighter assembly, perfectly at home in a street/strip ride IMO. The Ford 8.8 is a c-clip rear that's very similar to the 12 bolt. Most use the 12 bolt car versions, the 12 bolt truck version has a different gear set and a more rugged case which means more weight, also different cover patterns.

[danswrld]

Would be way easier to get a set of GM drilled (Yukon, Moser, Strange etc.) axles for your current Dana 60 than change the whole rear end. just my .02.

[tom s]

Unsprung weight is not the best weight for a race car.Tom

[Singleton]

Not a huge weight penalty.

From Hot Rod.com:
WEIGHT (POUNDS)
REAR AXLE COMPLETE

........W/O BRAKES .... W/BRAKES
12-bolt........ 171........ 210
Strange S60. 191........ 230
Currie 9-inch 174........ 238


http://www.hotrod.com/how-to/transmi...ear-axle-swap/

[J.C.you]

Originally Posted by Speargun

A buddy just told me that a Ford explorer rear end (8.8?) is a common swap. They come with a 3.73 posi and only need the spring perch changed.

Anyone done this?
Will an 8.8 hold up under 600-700hp?

Yes, 8.8 is a good rear. It is 4.5" bolt circle if you can go that pattern, unless you redrill. We did a S10 with a 8.8, bought a extra short side axle, shortened the long tube, installed the extra short axle, worked out nicely. I believe the final flange to flange measurement was 47 1/2"s. Cost of donor rear at u pull it was 80 bucs and 20 for the extra axle. Add the pinion to u joint adapter for 50 more clams. Best bang for the buck. Also add this rear has the disc/parking brake setup already on it.

[David Holmberg]

Keep what you have unless you have money to burn. If so, go with the S60.

[Speargun]

Originally Posted by J.C.you

Yes, 8.8 is a good rear. It is 4.5" bolt circle if you can go that pattern, unless you redrill. We did a S10 with a 8.8, bought a extra short side axle, shortened the long tube, installed the extra short axle, worked out nicely. I believe the final flange to flange measurement was 47 1/2"s. Cost of donor rear at u pull it was 80 bucs and 20 for the extra axle. Add the pinion to u joint adapter for 50 more clams. Best bang for the buck. Also add this rear has the disc/parking brake setup already on it.

I think I read that the 8.8 is 59 1/2" wide & has a 2" offset. So if I replace the short side tube & axle with another long side it should give me 61 1/2" width which, iirc, is just right for the 67 bird. The disk brakes are an added bonus.

When I look at the fact that 5x4.5 rims are a dime a dozen whereas 5x5.5 or customs are $$$$ and new Dana axles/seals, etc... are $400+ and I still have to find the correct drum brake parts or upgrade to disk, the 8.8 is looking pretty attractive.

Thanks for all of the input so far and keep it coming. I still have a little time before I have to make a decision, but I'd like to be armed with as much information as I can beforehand.



If I decide to sell, what's a Dana 60 like mine worth?

[i82much]

Originally Posted by Speargun

I think I read that the 8.8 is 59 1/2" wide & has a 2" offset. So if I replace the short side tube & axle with another long side it should give me 61 1/2" width which, iirc, is just right for the 67 bird. The disk brakes are an added bonus.

When I look at the fact that 5x4.5 rims are a dime a dozen whereas 5x5.5 or customs are $$$$ and new Dana axles/seals, etc... are $400+ and I still have to find the correct drum brake parts or upgrade to disk, the 8.8 is looking pretty attractive.

Thanks for all of the input so far and keep it coming. I still have a little time before I have to make a decision, but I'd like to be armed with as much information as I can beforehand.



If I decide to sell, what's a Dana 60 like mine worth?

Just my 2 cents, but I think unless you are doing road racing of some kind that rear drum brakes are actually the way to go. Even a lot of relatively late model pickups still use rear drums, they actually have more static clamping power than disc. They do overheat more easily, but given the relatively smaller portion of braking performed by the rear brakes, are you really going to overheat your rear drums?

And, here's the real reason I say stick with drum. In the event you have some kind of hydraulic failure and need the emergency brake to stop, what would you rather use - the rear shoes on your current drums, or on a disk brake style emergency brake?

[J.C.you]

Originally Posted by Speargun

I think I read that the 8.8 is 59 1/2" wide & has a 2" offset. So if I replace the short side tube & axle with another long side it should give me 61 1/2" width which, iirc, is just right for the 67 bird. The disk brakes are an added bonus.

When I look at the fact that 5x4.5 rims are a dime a dozen whereas 5x5.5 or customs are $$$$ and new Dana axles/seals, etc... are $400+ and I still have to find the correct drum brake parts or upgrade to disk, the 8.8 is looking pretty attractive.

Thanks for all of the input so far and keep it coming. I still have a little time before I have to make a decision, but I'd like to be armed with as much information as I can beforehand.



If I decide to sell, what's a Dana 60 like mine worth?

Yes, a lot of current wheels have the dual bolt pattern, 4.5 and 4.75". We are shooting for a 5.9 @ 3025lbs (do math on hp) this weekend with this stocker 8.8 rear with mini spool, so they can take some punishment. Gears are cheap too. Don't know what the posi setups are good for. There is a concern about the ring gear carrier being on the thin side with the stocker stuff. The stocker 31 spline axles are really beefy.

If this is a street car and not a dedicated race car, I like the 8.8.

[HWYSTR455]

How are you going to use the car, and what is the power level?

I've seen a number of local shops butcher rears shortening and modifying them. A professional rear shop that stand behind their' work is the best to use for something like that, say Moser or similar. You're for sure going to get a 'true' rear and quality work.

By the time you get a housing worked, tubes welded, shortened, big bearing flanges, etc, you're at the cost of a new housing anyway.

20 - 30 lbs of unsprung weight isn't something to shake a stick at. There's parasitic loss too, the beefier the rear, the more loss.

Have to consider the body too, 1st gen f-bodies don't have too much room under there, and in a number of options no way can you run a transvers muffler, and sometime no rear sway bar either.

Wheel options become a factor too if you don't have a 'standard' width rear. Add discs and it adds width too. If you have one made, you can compensate. Bolt in axles eliminate brake kick back, and big bearings take way more load, both great options.

I say a Moser 12-bolt is hard to beat for a 1st gen f-body, unless you have big power and focus on drag racing. A 12-bolt Moser housing built to order, is about 1200-1400 with options, and you can spend more than that having a used one worked.

.

[i82much]

Originally Posted by HWYSTR455

How are you going to use the car, and what is the power level?

I've seen a number of local shops butcher rears shortening and modifying them. A professional rear shop that stand behind their' work is the best to use for something like that, say Moser or similar. You're for sure going to get a 'true' rear and quality work.

By the time you get a housing worked, tubes welded, shortened, big bearing flanges, etc, you're at the cost of a new housing anyway.

20 - 30 lbs of unsprung weight isn't something to shake a stick at. There's parasitic loss too, the beefier the rear, the more loss.

Have to consider the body too, 1st gen f-bodies don't have too much room under there, and in a number of options no way can you run a transvers muffler, and sometime no rear sway bar either.

Wheel options become a factor too if you don't have a 'standard' width rear. Add discs and it adds width too. If you have one made, you can compensate. Bolt in axles eliminate brake kick back, and big bearings take way more load, both great options.

I say a Moser 12-bolt is hard to beat for a 1st gen f-body, unless you have big power and focus on drag racing. A 12-bolt Moser housing built to order, is about 1200-1400 with options, and you can spend more than that having a used one worked.

.

There is an article around somewhere dyno testing the three and showing the 9" with more parasitic loss than the Dana or 12 bolt. I seem to recall it having something to do with the position of the pinion gear but I haven't read it for a long time.

[Rob B]

Originally Posted by tom s

Good but heavy compared to the others.Tom

I had Moser build me a Dana for my car last year. The weight difference between all 3 rearends is around 20lbs or less coming straight from them.
The Dana also requires the least amount of HP to spin it. The 9" required the most. Does that make a difference in the overall performance of ones cars??? That's been debated all over the internet. My decision in going to a Dana was for the strength and honestly, it didn't cost that much more than the 12 bolt I had built for the wife's, car plus I was able to get 40 spline axles for the Dana, not the 12 bolt.
Once I added up all the extras to build a 9", it didn't make sense to me. I don't change gears enough for that to be a deciding factor.

[i82much]

Originally Posted by Rob B

I had Moser build me a Dana for my car last year. The weight difference between all 3 rearends is around 20lbs or less coming straight from them.
The Dana also requires the least amount of HP to spin it. The 9" required the most. Does that make a difference in the overall performance of ones cars??? That's been debated all over the internet. My decision in going to a Dana was for the strength and honestly, it didn't cost that much more than the 12 bolt I had built for the wife's, car plus I was able to get 40 spline axles for the Dana, not the 12 bolt.
Once I added up all the extras to build a 9", it didn't make sense to me. I don't change gears enough for that to be a deciding factor.

The reason people debate this so much is because the choices are all pretty close. The OP really can't screw this up if he goes with any of the 9", Dana 60, or 12 bolt.

I do seem to recall finding highway gears for a Dana 60 to be somewhat difficult but not sure if that is just for my specific carrier.

[Rob B]

Anymore, I wouldn't mess with a stock housing rearend unless it was exactly what I want/need for the application. You can build a rearend from Moser with big bearing ends, good 35+ spline axles, spool, gears, etc and all you do is put it in for not much more than a couple grand.
I spent $2400 on my Dana, with 40 spline axles, aluminum cover and to my dimensions. I was able to sell the 12 bolt I had under the car for a grand so I just applied that to the purchase of my Dana and everything worked out perfect.