Iits the clutch type right (not the cone)
Mopar 8 1/4 posi unit
These are both cone style
$300USD by the time I get it will be $700NZD plus! So the best option would be to get this one
DANA TRAC LOK POSI 8.25" 27 Spline MOPAR Chrysler 75101X Differential Carrier | eBay and use my install kit and my 3.21 gear set out of my current rear end?
This one is clutch style.
If you have the horsepower that can spin both wheels at once, fairly easily – then either (clutch or cone) type will work just fine (providing it’s not wore out, already).
It is the cars that put enough power to only spin one tire (without limited slip) all of the time – are the ones that are hard on clutches (or cones).
The 3.21’s are nice for both town and highway usage.
3.55’s are really nice in town gear with some highway usage (limited but can be done).
3.73’s or lower (higher numerically) would be really fun in town but would get irritating on the highway.
If you were to keep your 3.21’s, you can switch out to limited slip in your garage (recommended for a specialist), especially if you do not remove the pinion gear from your housing. If a person is going through that much work, installing all new bearings would be the way to go.
I believe you have what it takes to press off/on the large bearings. Just keep any of the shims behind the large pinion bearing and reuse.
If you are changing out gears – like to 3.55’s, the setup is more involved and there I would HIGHLY recommend taking to a specialist.
It is getting the distance of the middle of pinion gear to the center of axle shafts – which is the hard part. If using a gear made by Chrysler, you can go from end/edge of pinion gear to centerline of axle shafts – so a little bit easier. Aftermarket gear set are slightly more involved (nothing wrong with using aftermarket gear sets). Once set up correctly – you don’t have to worry about it, again.
The ring gear bearings are much easier to setup.
Chrysler makes a special took that makes setting the ring gear easier. It is a 1-3/16” hex (note I might be off on the exact size – going by memory) tool that is inserted through the axle tubes to adjust those bearings. I have a low tech tool in my garage for that (ie: a C-body torsion bar works great) purpose.
Depending on year the housing was made as to clearance space – but many times you have space/clearance to get a pair of snap ring pliers in to perform the adjustments (but not in all cases) They make a tool to use – but these do not work as well as 90 degree angle snap ring pliers.
In your case, It sounds like 3.55’s or 3.73’s
will increase the “smile” factor, a lot. The limited slip is a must – and sense you are in there, you might as well do both (
in my opinion).
I have no problem using either new or used gears or limited slip unit – but am hesitant on recommending an unknown or used cone type carrier – only because they are non-rebuildable. I can do the work in my sleep blindfolded so if I can save a buck – so I will reuse a cone carrier.
That said, sense parts are not available at every street corner down under – and sense clutch kits are (and will be for a long time) available – I suggest getting a clutch type limited slip.
Gears – as long as gears are not rusty enough to cause pitting, new or used gears will be fine (if considering changing gears, that is).
In my case, I have plans on driving my cars every day including driving to car shows out of state. 3.21’s will be fine for me. If I need a lower ratio (higher numerically) – I have a pair of short tires I can toss on that will give me what I want (until I put normal tires back onto car). Speedometer/odometer will be off - but I'm only talking about temporary usage.
Unrelated, I do have a new set of aftermarket 8¼” 3.55 gears up for sale (or trade)
BudW