7 1/4 Questions

[NSdartSW]

I have currently have an open diff 7 1/4 in my ‘66 Dart and would like to upgrade it as I’m giving her some more power up front. It would be nice to go to an 8 3/4 sure grip but I haven’t found one I can afford. I have come across an offer for a 7 1/4 sure grip at a crazy low price so I want to make sure the 2 7 1/4s are interchangeable as I’ve found different answers depending on where I look. The only thing is the sure grip 7 1/4 says it needs spider gears, how difficult is that task? Is it something do able in my backyard?
Thank you

 

[Dana67Dart]

Contact Cass at Dr. DIFF. he will have the answers

 

[NSdartSW]

Ok thank you

 

[junkyardhero]

spider gears for early 7.25's are NLA, spider gears for sure-grip 7.25's are made out of rocking horse ****.

your best bet would be to post a wanted ad here and hope somebody turns one up or parts of one and you could use the two to make one, or maybe they have some NOS gears kicking around.

good luck man!

 

[NSdartSW]

spider gears for early 7.25's are NLA, spider gears for sure-grip 7.25's are made out of rocking horse ****.

your best bet would be to post a wanted ad here and hope somebody turns one up or parts of one and you could use the two to make one, or maybe they have some NOS gears kicking around.

good luck man!

So the spider gears aren’t specific to the sure grips? I could take ones from a working set up and put them in the sure grip one then right?

 

[RustyRatRod]

Spider gears for open or sure grip 7.25 rears are unobtanium. The only ONE place that might have any will be AMS Obsolete in Georgia. I rebuilt a 7.25 sure grip not long ago for a friend and they were the only ones in the country with a new clutch pack. It was almost five bills.

 

[junkyardhero]

So the spider gears aren’t specific to the sure grips? I could take ones from a working set up and put them in the sure grip one then right?

no the spider gears are specific to the sure-grip, at least to my knowledge they are.

open is 2 spider(pinion) gears, sure-grip is 4

(caveat, later 7.25's were cone type and utilized only two spider gears)

but you could absolutely swap the parts between a working and non working set up.

 

[RustyRatRod]

So the spider gears aren’t specific to the sure grips? I could take ones from a working set up and put them in the sure grip one then right?

No. They are different open to sure grip. Even the two pinion cone style sure grips have different spider gears. The one thing that all three share is that they are damn near impossible to find. I would upgrade to either an 8.25 or an 8.8 Ford. I just got done with a Ford 9" for my 64 Valiant. I still have less than 850 bucks in it. You cain't touch an 8.75 for that.

 

[1973dust]

That's almost too pretty to hide under a car.