Tapered axle D44 FF conversion.

One of the guys on another forum has a tapered axle D44 with a FF conversion. Upon removing the axleshafts, the Power Lok axle spacer buttons came out. Are the spacer buttons required on a FF conversion?

 

no
with the FF, you no longer have an axle bearing that requires endplay.
the inner axle end would ride up against the button and provide for axle shaft endplay to be set at the outer end.
with FF, you only have the wheel bearings inside the hub, much like the front wheel bearings.
so you don't have the endplay tolerance to deal with

 

You know, that's what I figured but another guy brought up the point that there would not be anything to contol end play on the shafts since they basically ride on splines on both ends. FF shafts like an MB or 3/4 truck have a flange end to hold the shaft in place.

 

The snap rings in the hubs control the end play

 

I found out the FF axles he has do not have snap rings. I guess it won't hurt to reinstall the spacer buttons. They've been in there all this time. You guys agree?

 

I agree but make sure the buttons are not going to push outwards on the axle shafts, i.e. push them into the hubs causing thrust issues in the hubs or drive flanges themselves.

 

looking at the instruction sheet that came with my FF kit years ago:
"If using a powerlock, be sure the buttons haven't fallen out of the unit beofre installing the shaft."
No mention of remove them or not.
I took mine out.

 

Where can you buy flanged FF axles??

 

There were various manufacturers of full float type shafts to replace Jeep Dana 44 tapered type axle shafts.
AFAIK the OA axle shaft lengths could vary from one aftermarket manufacturer to another.

I have never seen rear full float axles with snap rings to control inward end float.
The centerblock spacer is normally used to control axle shaft inward end float.
The center block spacer will keep the axle shafts from contacting the pinion mate cross shafts.

The centerblock spacer for Powr-Lok differentials is a 3 piece assembly consisting of 2 thrust caps held together by a roll pin.
The small roll pin frequently shears off allowing the thrust caps to fall out of position when the axle shafts are removed.
By itself the roll pin is not important. It is only needed to hold the thrust caps in position.
Without removing the differential case you could probably install the thrust caps back into position by using some heavy grease.

I would reinstall the centerblock spacer to control inward end float of the axle shaft thus keeping it off the pinion mate shaft.
That is if the axle shaft OAL does not stick out too far into the driving flange.
The main concern is to get full spline contact inside the differential side gears and also inside the driving flange.

 

All of the Warn FF kits use a snap ring, Herm's axles can be had with a snap ring groove, all the ones R&P built back in the day had them (now can be had either way) Many of the old Smittybilt axles had them, some didn't.

 

I have a 4wheelparts FF kit (old) that does not have snap-ring grooves in the shafts. The kit was installed with a detroit locker and the centerblock was not installed, thus, allowing the axles to float inward. When I installed it, I didn't like how the axles could slide inward and limit the amount of contact area on the splines. I have lived with it for a few years with no issues, so I gues having as little as about 1/2-inch of the splines engaged in the hub is enough. If I were to do it again, I'd rather have axles that use a snap ring to limit inward "float". I think that if I were you, I would make sure the center block is installed since, as long as it is done correctly, it can't heart anything.

 

I have advised the fellow that it would be be a good idea to install the spacer buttons.