I was thinking of asking this a few weeks ago and the transbreak thread prompted me to do it

Has anyone actually run one of those nodular 8 3/4 cases from Yukon? (Or anyone else if they make them). Or do you know anyone that has? How did it hold up, what power/trans/weight and 60 ft?

I think Thumperdart has run one with success but his car doesn't see a lot of laps but it is fast!

In the end, you still have an 8.75. If you can source a dana housing they are cheap to build, especially when you consider the fallout of a broken rear end. You break the gear, and at minimum have to pull the trans and check the sprag and likely replace it. Do that more than once and you have arrived at your Dana 60.

There is probably some advantages to an S 60 housing but sourcing a housing and having it narrowed was way cheaper in my market.

I put one together for Bob {Prosport) in the green Duster he had for a while and it held up fine in a 10 second car. The case was pretty beefy with nice thick main caps. Just make sure you use the solid crush sleeve then you have the strongest 8 3/4 you can build.

Gus

I have one Moser built.
Nodular case, billet adjusters, etc.
Season before last I broke the rear in my Dart( see ET stuff in my signature) it was an older 489 case that had seen a lot of passes. I only footbraked it.
I only footbraked the new center section as well. Would like to try it using the brake, but don’t dare

I’ve built and used them. 3050lb Duster, 600hp, 9.9x’s, 1.3x 60’s with a transbrake and radials. No issues after 250+ passes. They can live under a light car. If your car is heavy, a Dana is the way to go, and is more efficient.

Another bandaid. It's still an 8.75. While you're at it, might as well waste some more money on one of those fab'd 8.75 housings.

If the housing isn’t the weak link then what do you think is the weak link in an 8 3/4?

Everyone runs an aftermarket housing for a 9 inch also, its not a bandaid for them?

To be clear I’m not saying that you’re wrong, because I don’t know, but I’ve not heard of anyone running these aftermarket housings and how much they strengthen an 8 3/4. I’d suspect they’d prevent pinion deflection to some degree over an OEM unit.

Ring gear

What about it?

I built my first Yukon 8 3/4 deal about 4 years ago and it runs, drives and is super quiet being I set the back lash tighter than most at about .007-.008 iirc. Not a lot off passes but I am on real slicks all the time now so we'll see how it holds up.....

Dom what weight and 60 ft, and how many passes so far?

The ring and pinion is the weak link. Also the style of centersection. You can't fix it.
All housings flex and need to be strengthened, but my point is you'll still kill gearsets in an 8.75 no matter what you do.

The 9" has WAY more aftermarket support, but a Dana is cheaper...if you don't mind limited gear ratio choices and a little extra weight. These 2 each have their place depending on budget and the application.

If you are interested, I carry a Yukon (lightweight nodular iron 489 casting with steel caps) as well as a Super-Duty nodular iron casting with Ford 9" style cr-mo caps:

https://www.doctordiff.com/8-3-4-nodular-iron-casting.html

Around 3000 lbs now with the QA-1 k member, lower control arms and Hotchkis heimed upper control arms. Only about 20 passes with a 1.33 best 60 at the track and lots of street miles...I have a new 8" DICE vert to go in to replace my 30 yr old 8" Continental so hopefully a new best is coming...Oh, always footbrake which helps....

At some point you will kill them sure, but there are guys going single digits GM 8.5s, Ford 8.8s, and GM 8.875s. I find it hard to believe that low 11s are the limit for an 8 3/4 ring and pinion based on the ring gear diameter alone.

A Dana is cheaper if you cut down a truck Dana and can get one for a good price - in some parts of the country its hard to find a truck Dana that people don’t think is worth $500. And you have to have the skill to narrow one or a shop around who can. I agree Dana 60 is the ultimate, but the aftermarket housing “band aid” might be pretty effective for a car thats not in the single digits at 3800 lbs. No one will ever know if they all go D60 or 9 inch Ford, just interested to know how much of a difference this makes.

If no one ran an aftermarket housing on a 9 inch I don’t think they would be in the conversation either, because their OEM housings are weak even with the built in crutch support.

I have run all three under my Savoy and it currently sits on a Dana. When I got into the 11's I pulled the 8 3/4 and put a 9 under it because I knew it was stronger than the 8 3/4 with both rears being stock. My 9 had a factory "N" case with 33 spline. Moser axles and spool. It did good and is now under a 67 Camaro running low 9's with the same 4.56 gears I installed 18 years ago. The guy with the Camaro had an early B-body Dana under it and we made an even up swap. My Savoy isn't that fast with the best 60 being 1.47 and best time of 10.91 at 124 mph.
I am currently collecting parts to put a 9 back under it just because it's easier to work on.

Gus

I'd say that there are many BB/SB Mopars in stock eliminator with #'s in the low 10's with 8 3/4 rears. Most R&P are changed every 300 passes or less. You see the weight transfer of those cars and the complete rear takes a pounding. The days of the good(metallurgical) R&P for the 8 3/4 are not so good anymore. India/Italy/China are not the best sources. The 8 3/4 doesn't sell enough to warrant "Good Quality" attention anymore. Had to find good Dana parts too. The 9" is glory kid now and all resources are going that way,

I had a set of 4.56 Masario Italian gears in a 9 inch that were really nice and never seemed to show any wear even after hundreds of passes. I wish I had another set but Summit changed suppliers and they no longer use them for their house gears.

Gus