How To Recondition a Sure Grip Cone

-
RustyRatRod

RustyRatRod

I was born on a Monday. Not last Monday.
FABO Gold Member
Joined
Jun 7, 2010
Messages
104,699
Reaction score
102,194
Location
Georgia
RustyRatRod submitted a new Article:

How To Recondition a Sure Grip Cone

This is a how to on reconditioning a cone style sure grip unit. This is not a boni-fide approved repair in any book or manual. I have done a LOT and I mean a LOT of them like this and never had a problem.

I am doing this unit for our member "73SwingerBuild". As you can see, it's a pretty clean unit out of the box. To disassemble it, simply remove the eight bolts on the ring gear flange. The preload springs will push the unit apart.

EDIT: This thread is purely a how to. I don't intend for it to be a discussion of the operation of the unit. We have more than one thread where we can argue about that. Please don't clutter the thread with discussion or arguments of operation. Thank yall for understanding.

View attachment 1714969839

Once apart, here is what you have. Two screw type cones that lock into each half of the differential case when power is applied. It is a very good design, but, not rebuildable by any approved method. But we are gonna fix all that up.


View attachment 1714969840


A side shot of the unit shows how it is assembled.


View attachment 1714969841


Sorry for the blurry pictures. I am tired and I was shaking. Here is one half of the differential case. You can plainly see where the action takes place here. The cone screws into the case and locks into position locking the axle to the case when power is applied.


View attachment 1714969842


Another shot with the flash. There's no mistaking what happens here. The cones seat hard in the case halves and lock the axles to the case causing the sure grip function.

View attachment 1714969843


Here are the sure grip cones. You can clearly see where they have bottomed into the case, rendering the sure grip function useless. Other than this wear, the unit is in very good condition. The shiny area on the outer edges in this picture will be where the machining takes place. Once this area is machined down, the cones will seat against the sides of the case again and restore the sure grip function. When I am done, it will likely drag the outside tire a little bit on tight turns until it breaks back in because it will be like new again.


View attachment 1714969844


Here is the unit exploded. As you can see, there are not that many pieces. It is not a complex unit. I like simple and simple is what the cone type sure grip is. When I get the shims and get the machining done, I will go over the reassembly.

I hope you have enjoyed this so far.

View attachment 1714969845


Here is the unit all cleaned up, blown off and sprayed down with PBlaster to keep it from flash rusting. The spider and side gears look great with minimal wear. I'll get the cones machined later today and the shims may even be here later today as well. We'll see. The old tapered axle in the background is used to line the cones and side gears up. It would be a double barrel bastard to line up once it's together.

View attachment 1714969846


Alright, here we go. To assemble, first, you need two 30 spline 8 3/4 axles. Clamp one in the vise, as shown and slide the small side of the case over it. Like this:

View attachment 1714969847


Oh yeah, I almost forgot. Here are our freshly machined cones, ready for installation.

View attachment 1714969848


After dumping a little 90 weight into the case half in the vise, take the cone and slide it over the axle splines and into the case half.

View attachment 1714969849


Next is our shim that helps restore preload and gear mesh. Don't forget to add a little 90 weight as you go.

View attachment 1714969850


Next, add the side gear, and a little 90 weight.

View attachment 1714969851


Next, assemble the thrust block, spider gears and spider gear washers, bottom spring plate and install the cross pin and it's retaining pin.

View attachment 1714969854



Now, install the preload springs and the upper spring plate. Don't forget to slob some 90 weight on each time you add a part.

View attachment 1714969855


Next comes the opposite side - side gear and shim. Don't forget the 90 weight!

View attachment 1714969856


Now comes the remaining cone.

View attachment 1714969857


Now lower the flange half of the case over the assembly.

View attachment 1714969858


Start two bolts across from each other. You're going to have to push the case halves together to start the bolts, because we've shimmed the unit back up to where it once was. Just get the two bolts started a few threads and leave them loose.

View attachment 1714969859


Take axle number two and install it in the top case half to align the side gear with the cone. Make SURE the axle goes through both the cone and the side gear. If it does not, it will be impossible to align them once the unit is torqued down. You will have to loosen it all back up.

View attachment 1714969862


Get all of the bolts torqued down and remove the axles. Here is the unit all reconditioned and ready to go.

I hope you have enjoyed this. I did. It was fun.

View attachment 1714969864
Click to expand...

Read more about this article here...
 
Last edited:
It'll be probably Monday before the shims get here so yall bear with me.
 
Super...gooood stuff man...and with pics...simple and easy..you are the man RRR...about time somebody showed how its done....when doubters become believers
 
jos51700 said:
Where do the shims come from?
Click to expand...

That's proprietary. I caint divulge all my secrets. I did a lotta measuring and figgerin years ago and found some that work. This is gonna end up around 100 or so bucks plus shippin. I'll be more than happy to do some more for yall if you want me to.
 
Heya "Trip"

Good stuff. Thanks for sharing!
I love this stuff.
 
Hey rusty, while I still disagree with some of the description of operation of these units, its a really cool thread to show guys how to refresh one, kudos to you on that!
 
Sorry I have not gone further with this yet. I overdid it today movin some stuff around. I will update as soon as I get more done.
 
You must log in or register to reply here.
-

Back
Top