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Got the new 9 inch from Doctor Diff

A Dana 60 does require LESS hp to turn.
True, but the low setting hypoid ratio that causes a 9 to eat more power than a dana, also results in longer, stronger teeth on the ring and pinion, contributing to overall strength. I think that if the 9 actually ate a lot more power than a dana, there wouldnt be ten nine inchers under racecars for every dana.
On the other hand, when the time comes to upgrade my 8 3/4 , im gonna buy a dana.
 
I went with a Quick Performance Ford based 9" rear axle assembly in my wife's 65 GTO after the factory crappy Pontiac rear gears exploded.
It's way overbuilt with the options I chose, but I never have to worry about any failure in that assembly, ever...
I already had a Dana 60 in my V-code Roadrunner, so I put money into the Strange chromoly steel driveshaft, slip yoke, pinion yoke and U-Joint caps-ALL chromoly steel. 1350 solid U-Joints.
When I get all the over the top stuff I bought squared away, those areas will be ready to go when I have to dump another pile of money on building out my Bill Mitchell Products 541 aluminum RB motor. Everything aft of the block is ready!
Very nice setup AndyF, and I have no doubt that you did it right.
 
The 9 inch will replace the S60 that is currently under the Duster. I got a new S60 with 3.23 gears from Doctor Diff last summer for the Coronet.
View attachment 1030214
What boxes did the 9" check that the S60 didn't?

The reason I ask is that will probably upgrade my 8-3/4 in the future, and what you are taking out is what I would have gone with.
 
What boxes did the 9" check that the S60 didn't?

The reason I ask is that will probably upgrade my 8-3/4 in the future, and what you are taking out is what I would have gone with.
Simple. Gear ratio available in a nine not available in a dana 60, as previously stated by Andy.
 
That’s because every heat manufacturer put tons of r&d into the 9. Had that been done on the 8 3/4, there would be **** loads of gears too choose from. And just a tad bit more info, those 9’s use a Green style bearing, so there goes the theory that Timkens are the best.
 
Ok so the ratio. Didn't know what was available for what.
Roughly twice as many ratio choices available in a nine, compared to a dana. And some of the available choices for a dana are ludicrously low. A 6.17? How about a 7.17?! Until a little while ago, you couldnt get anything higher than a 3.54 for a dana either.
 
That’s because every heat manufacturer put tons of r&d into the 9. Had that been done on the 8 3/4, there would be **** loads of gears too choose from. And just a tad bit more info, those 9’s use a Green style bearing, so there goes the theory that Timkens are the best.
My 9 inch uses the big Set 20 tapered roller bearings. They are a sealed bearing so you don't need an adjuster but they are a tapered Timken roller bearing rather than a ball bearing. https://www.strangeengineering.net/product/3-150-1-562-tapered-axle-bearing-with-seal-ea.html/
 
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Uh, you could get 4.10 in a Dana 60 back in the day.

Sounds good Andyf.
 
Roughly twice as many ratio choices available in a nine, compared to a dana. And some of the available choices for a dana are ludicrously low. A 6.17? How about a 7.17?! Until a little while ago, you couldnt get anything higher than a 3.54 for a dana either.

Yep, the Dana 60 gear choices are what you would expect for a truck rear end rather than a car rear end. I have the first set of 3.23 gears that Doctor Diff produced for the Dana 60 in my Coronet. They work pretty good with my Doug Nash 5 speed but if a 3.08 gear was available I would've gone with it. A 3.08 would be perfect with the 3.27 first gear in the Doug Nash. I suppose I could switch my Coronet over to a 9 inch but I just don't think I'm up for all the extra work.
 
Uh, you could get 4.10 in a Dana 60 back in the day.

Sounds good Andyf.
Yep, and a 4.10 is lower than a 3.54. Until Dr Diff had 3.23s made for dana 60, a 3.54 was as high as you could get. Thats why there is such a thing as a dana 61. Higher gears than you could get in a 60. Looks the same as a 60, but the pinion is in a different location in the case. Most common ratio in a 61 is 3.07.
 
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Yup, my brain fart. You’re are correct.
 
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