Fitment issues Duff coil spring lower cups and custom axle

[Mountaineer1]

New member, in a bind. Literally. The build is a 66, East Coast Gear Bronco axles with GM 1/2 ton steering ground up. The issue I am having is the James Duff lower coil retainers contacting the larger Inner C on the custom D44. See Pics.

Now I think I have some potential solutions in varying degrees of P.I.T.A. and cost.

1. Clearance Duff cups
2. Clearance C or re-drill cups
3. Put original cups on T. Rex arms and purchase the sway bar brackets that sammich between the cups and the upper arm
4. Same as 4, but use Migs retainers.

Comments
1.&2. I don't want to clearance the cups, and I certainly don't want to cut inner C's. Further, redrilling the cups may create unforeseen spring and sway bar fitment issues down the road.
3. Will O.G. cups sit right on Duff arms, and will they fit the Duff springs?
4. Are Migs' retainers oversized like Duffs? If not, will they clear? (Migs, I need some dimensions) And if so, will they fit the Duff springs?

Yes, I know I need to do the update bio thing, and yes, I have contacted Duff. One of the ideas they had is listed above. I will not tell you which one it is. This is not a Duff issue. This is a custom axle issue. The axles were listed as direct fitment, and they probably do fit with the stock parts.

Thanks for the help and ideas in advance.

https://i.postimg.cc/GmSPgK36/IMG-4628.jpg
https://i.postimg.cc/jdthDCk3/IMG-4629.jpg

 

[EPB72]

I have migs cups on y Rex arms and older duffs coils the coils fit the retainers with zero slop possible very slight interference fit,, I don’t run a sway bar so no comment on that ,,,, like the fact that the migs retainers has the little step down to account for the end of the coil like oe as apossed to the others that are just flat ,, Or clearencing what you have should work as well ? The norm most everything needs some work to make fit ,,

 

[migs]

Thanks for the interest. Yes, my coil cups are oversized compared to the factory ones but I believe slightly less in diameter than the flat cups.

The base of mine are roughly 5-3/4” in diameter, but I did offset the bolt holes to match the same spring placement of the factory cups.
One other factor in the offset was to aide in clearance issues I was having with the flat cups and custom track bar riser brackets.

So that does mean that it places more of the cup base towards the knuckle side, and that dimension is just under 3-1/4” from the center of the bolt holes to the outer edge of the base.
And it does get tight in that area, but the outer edge does start to rise up there which can help in some instances and may possibly clear with something such as a sway bar bracket piece spacing it up.

Oh, and yes they should work with any of the aftermarket or stock Bronco coils, haven’t ran into any issues with that.

 

[DirtDonk]

Where will your coils fall naturally? In other words, center the axle without the track bar, and let the coils hang.
Reason I’m asking this is, if the coils hang inward, even slightly, you could re-drill the holes in the existing spring cups to move them inward.
If that doesn’t put them in a natural position however, what about spacing the cups upward?
If you weld a plate to the base of the cup, moving them upward a given amount, how much higher would they have to be to start clearing the weld and/or the steering yoke (inner-C)?

Or is the interference just too much for that, and you would have to raise them to an unnatural height?

 

[DirtDonk]

And yes, I understand that if you modify them, they can’t be returned. So if returning them is even one of the options, then neither of my suggestions hold water.
But if either one looks like a possibility, it might be worth the gamble.

 

[hsach]

OP I have the same issue as you. Front is a Tom's Mag Dana 44, and the Duffs cups interfere. I decided to clearance them, pretty easy job and I will take them back off to powdercoat. I also thought about picking up some of Mig's cups, but decided to see how much material needed to be removed. If I wasn't going to run a swaybar, I would use Mig's, didn't know about his until after I purchased the current ones.

 

[Mountaineer1]

So the east coast gear axles I have use a 1 ton C. Thicker and taller. I think I would need to take about a quarter inch or more out of the cup. I have a welder and am capable of it but I want to entertain options first. I like the mig cups and if they are tighter than the duffs and I have any clearance I would like to go that way. MiGs reached out and he is a right on kinda dude. He’s sending me a set for testing. I’ll post an update on it. I may use his cups if they fit and either use the Tom’s Hellwig brackets or cut the brackets off the Duff and weld them on to MiGs.

In case anyone wants to know these are my axles
https://eastcoastgearsupply.com/i-23994626-66-77-early-bronco-dana-44-front-axle-assembly.html

https://eastcoastgearsupply.com/i-23994628-66-77-early-bronco-rear-9-axle-assembly-35-spline.html

 

[Madgyver]

Get past it and trim corner of cups. Make them fit.
Coils are round and you don't need full support of those massive cups.
I have the same issue with my planned build of my D60. My solution= Trim the coil cups, They don't need the corners, just cut enough so they clear without touching.
I had an issue on the Firebronco with the GM 1 ton TRO install hitting the aftermaket gear cover.
My solution... see pic

Remember no rules. Make it work and enjoy your ride....