Different length rear axle shaft threads on either side?

B

Banditorama

Senior Member
I was driving the car today when some nice gentleman in a Jeep informed me my rear driver's side wheel was wobbling. I got home and sure enough, with the rear jacked up it had about 1/4" of in and out play.

I took the wheel off and the axle nut was extremely loose. With the nut tight enough to take the slop out, the castle nut is ~1/8th of an inch further down than where the cotter pin goes. I attached a picture of both sides so you can see what I'm talking about

Anyone know what is going on here?

I noticed I have two different style drums. But, they're both the same overall length
 

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You have an early hub and a late hub. They should fit similarly but this shows that “somebody’s been here before”, so nothing is off the table. On the weird side, either someone has turned down the axle taper, opened up the hub, or both. You can figure out which by swapping sides. I’m not sure that installing the axle sleeves available from the vendor will give you enough movement.
 
JayJay said:
You have an early hub and a late hub. They should fit similarly but this shows that “somebody’s been here before”, so nothing is off the table. On the weird side, either someone has turned down the axle taper, opened up the hub, or both. You can figure out which by swapping sides. I’m not sure that installing the axle sleeves available from the vendor will give you enough movement.
Click to expand...

I don't think shims will do it either. With that much thread showing, the drum would be so far in that it would be rubbing the backing plate but the OP hasn't said anything about that so I assume everything is OK there. If that hub were shimmed enough to move the hub out that far, the brake shoes would not be fully within the drum.
If this is a driver car, I'd be tempted to use a different type of nut that doesn't rely on a split pin - maybe a Nyloc nut or a not so strong Loctite in there to hold it. That is assuming everything is otherwise OK when it's done up.
 
If it was loose enough that it was wobbling, and who knows how long it's been that way, I'd be concerned that the hub has been wallowed out. But as Planojc mention, if the drum hasn't been rubbing on the backing plate, I'd get a tapered axle shim from a vendor and snug it up good and tight, adding that missing flat washer behind the castle nut. It could be fine after that.
 
The drum does not rub on the backing plate (surprisingly). After I took those pictures I went out and got a couple 5/8 washers and put them on the shaft. The cotter pin now goes through the castle nut correctly with those under it.

Is this assemble supposed to have washers under it? Neither side did on this car

How would I get this much difference between the two shafts? Both axle housings are the same length on either side, the drums are the same length, and the backing plates are the same thickness.
 
Maybe the differential has been shimmed for ring rear pinion clearance and or bearing preload that has caused the assembly to move to one side ? Or maybe the rearend is needing major repairs, if it’s not noisy I would just keep an eye on it.
 
After doing some research, nothing about the way these were installed was right. Should be Hub then Fiber Washer then Steel Washer then Castle Nut. I had previously pulled off both the front and rear passenger's side drums and found new brake shoes/hardware on both and inspected the drums. Everything was new looking so I just put it back together how I found it. Lesson learned: just because the parts are new doesn't mean they were installed correctly

The rear hubs were put together as you would the front, meaning just snugged up. I'm reading that the rears are supposed to be torqued down to ~100lb/ft. I guess my plan of action is to get all the proper hardware, some of the axle shims, and re-assemble it all correctly. I'll get some Prussian Blue and check the taper fitment between the hub and axle. Then just go from there as to what I need to do to get it right

Hopefully it doesn't need a whole rear end rebuild or anything too major. They do a car show downtown on the 15th of each month from May through September that I've been wanting to go to since I got the car last year. I spent all of last summer going through the car and then missed last month's show because I had it torn apart replacing the head gasket.
 
Bigsnapper43 said:
From the picture it appears to me to be a '31 castiron drum. I've only seen a couple of these in my time.
Click to expand...

In the first picture or the second picture?

I measured the drum thickness on the front/rear passenger side when I went through them when I got the car last year due to having 0 braking power. All the components were basically brand new and the drums on that side were in perfect shape and had never been turned. I didn't bother checking the other side, I just adjusted them properly and its capable of stopping on a dime now. I figured someone wouldn't do a full brake job on one side and not the other. Now I'm not so sure

That's one more thing to inspect.
 
I see no mention of either of the axle keys being installed here!

If not maybe the axles on both sides have been spinning inside hub tapers.


In that case the tapers on both axles and both hubs could be worn!
 
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