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Good luck, Dougo. If you're replacing the bearings because the rear wheel wobbles a bit, know that in a vast majority of cases, it's NOT due the bearings but an inadequate press-fit dimension on many factory stub axles. The very hard bearings running loose causes fretting of the mild steel axle, wearing a channel in the shaft surface. Less than 0.001" of wear will cause a wobble and I've seen 0.125" or more. Do not bother trying to fix a bad axle; I've repaired dozens and I recommend using a far stronger billet axle, or the replacement units from the vendors, made of better steel to the right dimensions. Note you'll also need a hydraulic press & some other uncommon tools.
You should also ensure that the rear-wheel play is not in the bushings or the pivot rod that holds the uprights to the A-Arms. My bushings were worn, and that's where my rear-wheel play was coming from.


See the write-up on #5357 in the Specific Car Forum..... My buddy made me a set of bushings, but I believe the vendors sell them too.

You probably want to grease those bushings while you are working on your suspension, as well.
Here is the home made one we've been using. It was made from a 1-11/16" 3/4" drive socket.

Here (http://pantera.infopop.cc/eve/forums/a/tpc/f/7350045562/m/8731056356) is how we held the axle assembly while loosening the axle nut, YMMV.

Holding the axle is only part of the battle, keeping the socket on the nut is the other part. The 2x4 enabled us to put down pressure on the socket, otherwise it just pops up and disengages. Again, YMMV, but somehow you'll have to do the same.

I suppose an impact wrench would also work for the loosening, though it may shear off the little fingers if you pound away for too long.

Good luck.

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Larry's homemade unit is designed as the original OEM Ford socket, with external teeth.

While certainly functional, it is known to slip off the nut, or to shear off one of the four teeth.

There is an improved version that hopefully is the only version still being sold by the vendors.

I bought mine from Mark Johnson at IPSCO. One-man machine shop with excellent attention to detail and quality.

Socket accepts a 3/4" drive, or a 1 1/4" socket.

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A couple of other details: first, on the threaded end of each axle will be a stamp- either 'D' or 'S'. S- 'sinistro' denotes a LEFT-HAND Thread. Owners have BROKEN original sockets trying to unscrew a nut the wrong way.

And the torques you're dealing with are 'above 300 ft-lbs'. for both thread nuts. They can be considerably higher if someone added Lock-tite to the nut. Don't be worried about stripping threads- SAE says that thread size will hold 1100 ft-lbs in mild steel. Large torque wrenches are occasionally available cheap on E-Bay because they're so bulky. Even though the handles dismount for storage. Air-impact wrenches, whacking the nut notches with a punch and other blacksmith techniques are NOT advised. I bought a 0-600 ft-lb Snap-on torque wrench for less than $100 off E-Bay some years ago. Snap-On still makes that model for $500 retail.
Bosswrench and others,
Yea, thanks for all the support! I swear this forum has the best people on it. Why I'm I doing this axle thing? The inside bearing on the R/R is spinning in the housing. I noticed this a couple years ago, I've kinda ignored it. I want to fix now. I'm also going to do the "A" arm bushing while I have everything apart. No doubt I'll find something whilst I dig into this project. Oh, also I've got George in my "hood" for all the info that one could need.
Dougo, there are tolerances on everything mechanical and while the bearings are supposed to be slip-fit in the upright and a light-press-fit on the stub-axle, I've seen cars in which this was reversed. If the bearing has been spinning inside, it may have thrashed way more clearance in the cast iron upright than DeTomaso planned. It is not a real simple fix, but if a new bearing is still a sloppy fit, what you can do is strip the upright, take the upright and a new bearing to a local machine shop (mom & pop places are best) and ask him to bore the thrash-marks out and shrink-fit a steel spacer in, then bore that for a proper fit on your new bearing. Far cheaper than finding a spare upright.

My friend Shelly's solution likely will not work for you. She's very cute and had much the same problem with her Pantera. Shelly put on a scoop-neck top & short skirt, then went to a bearing supply house in San Jose, CA with her parts. She told me she got the undivided attention of 3 countermen who spent hours going through their entire stock of bearings to select-fit a couple to her upright and stub axle, without machining. Then they wholesaled the bearings to her. Man, sometimes life ain't fair... Good luck.
One other point to remember is that the axle nuts are cinch nuts with a cut in them and distorted thread so they can feel tight and yet not be fully tight. These style nuts are designed to be single use.

I also recommend to check tolerances on all the spacers and renew the chamfered thrust washer on the axle. The axles were rebuilt on one of my cars and the thrust washers not replaced; I had to rebuild them again within a couple thousand miles.

Julian
Part #17; part #12 is the hardened load-spreading spacer that touches the flange & outside bearing. The #17 washer has a flat side and a conical side; many of us put the flat side against the tapered cut in the splined axle adapter (#16), to cause the washer to flex and act as a belleville-spring, further locking the axle nut. There are no known factory directions for any of this & both washer positions work.

If you decide to order new nuts ($16 ea), there are some different ones that have been used over the years. One OEM is a lightweight half-height nut that has little for a wrench to grab and after a few uses may so round off the notches that you can't torque it using a factory wrench with tab ends. It is not split. The second OEM nut is a full-height split style and withstands reuse better. And some vendors have repopped the nuts in a better grade of steel- usually, the split full-height style. So what you get may look different. As Julian said, the full-height type are horizontally saw-cut 1/3 of the way around so the top twists under final torque, locking the nut. Untightening may, or may not untwist it to the original point. Make a note of the run-in torque when starting to tighten a used nut, and ADD that to the 300 minimum ft-lbs needed: if run-in takes 30 ft-lbs, tighten to 330 ft-lbs minimum. Higher is better; lower is flirting with disaster and guessing is even worse.

Before assembling an upright, hang the stub axle from a wire and smack the flange with a steel hammer. If the axle is cracked, it will sound dull; a good axle will ring like a bell. The crack will ALWAYS be in the chamferred area where the shaft and flange meet, and may not be visible. I once weld-repaired a worn axle, and had the hidden crack snap in two in the driveway as the car was being rolled out for a test drive. I've found cars with rewelded flanges..... scary!

Finally, p/n 14 is a mild steel spacer that often gets chewed up on one end or the other. Some shops lathe-cut or dress the spacer ends flat. I don't bother. The inner bearing is located by the spacer, not by a step in the upright bore, so it moves in or out during torquing. But at some point, a dressed-flat spacer will be shortened enough that the splined outer adapter (#16) will bottom on the stub-axle splines (#11) that are tapered in depth on the part furthest away from the nut, before compressing the spacer. Bad things then occur and you get to do this all over again.

For those that want to play around in here, the Gr-3 used optional 10" wide Campys & 295-50 tires, and to counteract the expected extra traction from big tires, there was a double-row inner ball bearing used. This bearing was the same OD as the stock single-row bearing & drops in. To compensate for the extra bearing width, the steel spacer was shortened the exact same amount. With GT-5 and -5S cars and their 12" wide Campys, the inner bearing was again widened and changed to a straight roller (NOT tapered) bearing. The spacer used here was about 1/2 the length of stock. This non-tapered roller bearing is NOT a drop-in; it's the same OD as the front ball bearing so it requires a remachined upright- stock on the wide-bodies. Note that with proper bearing press-fit and non-pro-race use, NONE of these optional wheel bearings are needed with giant tires.
Just to be clear #12 the outer conical thrust washer is what was bad on my GT5.

Also if taking Jack's advice on alternate bearings be aware that later GT5 axles are completely different than earlier cars, they are a stepped axle on the outer side and a lot harder to come by.

Julian
Hi Kid and Julian,
thanks again for the reply.
It looks like that there is a big difference between the axles from a regular Pantera and a Pantera Si.
The outside of the nut from a Pantera Si is 38mm
The inside is about 23,5 mm.
It's for sure that the Pantera Si has a lot of different parts and body panels, axually the Si is a complete different car
Simon
quote:
Originally posted by Bosswrench:
Dougo, there are tolerances on everything mechanical and while the bearings are supposed to be slip-fit in the upright and a light-press-fit on the stub-axle, I've seen cars in which this was reversed. If the bearing has been spinning inside, it may have thrashed way more clearance in the cast iron upright than DeTomaso planned. It is not a real simple fix, but if a new bearing is still a sloppy fit, what you can do is strip the upright, take the upright and a new bearing to a local machine shop (mom & pop places are best) and ask him to bore the thrash-marks out and shrink-fit a steel spacer in, then bore that for a proper fit on your new bearing. Far cheaper than finding a spare upright.

My friend Shelly's solution likely will not work for you. She's very cute and had much the same problem with her Pantera. Shelly put on a scoop-neck top & short skirt, then went to a bearing supply house in San Jose, CA with her parts. She told me she got the undivided attention of 3 countermen who spent hours going through their entire stock of bearings to select-fit a couple to her upright and stub axle, without machining. Then they wholesaled the bearings to her. Man, sometimes life ain't fair... Good luck.


Thanks for the advice. I'm sure you know with everything you have worked on, you never know what your going to find until you open it up. we will see what's happening when I get it apart. If I remember I'll shoot some photos' so others can learn, or beware. BTW, I look terrible in short skirts...Plus I always cut myself when I shave my legs.
I could check the tread one of these days.

Locking pins is what we use, put I'd be surprised nuts so small would be available with pins - the pin bolts would then become extremely small, and other than that, forces on a car axle are nothing to what we deal with. Some Loctite (red or blue) would do the trick too!
The nut is deeply inset into the splined halfshaft end, causing difficulty with most pins or safety wires. When I experimentally converted a couple of uprights to tapered roller bearings in the '90s (which don't need the bearing spacer nor high torque on the axle nut), I drilled a small hole through the side of the splined adapter, tapped it and ran a long 10-32 allen bolt thru. The end of the little bolt is positioned to enter a notch in the stock nut and mechanically locks the assembly.

The allen bolt could be safety-wired, but in 15 years of test driving, I've not seen any movement of either the allen bolt or the axle nut, which is only torqued at 8 ft-lbs in this installation. Due to the close placement of my little bolt to the center of rotation, no imbalance has ever been detected, either. But for perfectionists, TWO such bolts 180 degrees opposed would solve this apparently theoretical problem.
It's a Snap-On model 602-AL, 3/4" drive. The handle pops off the shorten the assembly for storage; everything appears to be stainless and/or chrome plate. A 3" dial tells you the torque but because you're 3 ft away from the dial when working the handle, it has a drag-along needle that forms an electrical contact powered by a AA battery. This arrangement lights a penlight bulb at your preset torque so you need not have a helper leaning over the dial. Worked fine the dozen or so times I used it. When I was building rocket motors for NASA, my crew used a 0-1000 ft-lb variant with the same lightbulb to torque nozzle bolts. It had a 1" drive and should have come with wheels....

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