GM 12 bolt mini-spool install and Poly Performance SF shafts

[fromme]

I was looking for something to replace the Aussie locker in the rear axle, but with a small price tag. I heard a GM 12 bolt mini spool can be made to fit in a Toyota 9.5 carrier so I decided to try it for myself.

I picked up a Richmond Gear mini spool from Amazon for $62 shipped.

Remove the Aussie locker or spider gears if you haven't stepped up to a locker yet.

I started by installing the two side gears. They need a hair taken off where they slide in to the carrier. About .0010 is all. I used some emery cloth and just made them shiny. They fit right in.

You will need to grind a little on the c-clips. They need to be ground to a horseshoe type shape. They need to fit in the wide grooves on the side gears.

 

[fromme]

Next I turned my attention to the shafts. I had ordered a new set of alloy shafts from Poly Performance. They are overpriced IMO, but they are also the only SF shafts available. I cried once and pulled the trigger. One thing I noticed is the factory shafts are actually larger until they neck down at the splines. Kind of strange to me, but I am not a metalurgist so I don't have an opinion on why.

I did not have the foresight to buy new wheel studs. So I hammered out the old ones and pressed them in the new shafts. I'll get some studs later and press them in the old shafts so they will be functional spares.

I went ahead and reused the dust shield that was on the back of the factory shafts.

I slid the shafts in the axle and then installed the c-clips and snapped the shafts back out which pulls the c-clip tight against the side gears.

I slid the two center blocks in place and then installed the center pin. I did not have to grind on the center blocks like I read. They went in snug, but it was no problem.

 

[fromme]

Great, I think I'm done. Now here's where there was a minor problem. I had no axle end play on the left side, but excessive end play on the right side. I'm running 5.29 gears, which as you know has a pretty small pinion gear. As a result the carrier is set up over toward the right a good bit more than it would be with stock 4.10 or like gears. This is a factor with the mini spool since the ends of the shafts do not contact the center pin, and there is no spacer or side thrust washers used with it.

Even though the destructions said not to use the side thrust washers, I chose to remove the right side gear and install a thrust washer using it a shim. It worked, and frankly it made the whole set up look better. Before I felt that there was too much clearance between the two side gears where the blocks fit in to the grooves. This not only tightened up that distance, but fixed the excessive end play on the right side.

 

[lcwizard]

not surprised it's a close fit. The most common locker for the 40 in the 70's was a 12bolt
gov-loc. Very minor machining. Mainly had to slot the ring gear hole a tiny bit to match the bolt circle of the cruiser ring gear

 

[fromme]

To sum it up, this was a cheap and easy install. Will it work? I hope so. Driving it around so far has been great compared to the Aussie. No more clanging and bucking, and sudden unloading. I can coast and decelerate around a corner and it's smooth.
The downside is the obvious, lots of tire scrub, occasional tire squalling and I will wear tires out sooner. But it's not my daily driver so I don't care. The pluses outweigh the minuses.
I should have done it instead of the Aussie. One day maybe I'll have the extra cabbage and can do an ARB, but this fits the bill in the meantime.

 

[fromme]

not surprised it's a close fit. The most common locker for the 40 in the 70's was a 12bolt
gov-loc. Very minor machining. Mainly had to slot the ring gear hole a tiny bit to match the bolt circle of the cruiser ring gear

Interesting. It would stand to reason that a full spool may fit then?

I suppose at this point, I'm limited to the strength of the carrier. Hope it holds up.

 

[Fast Eddy]

I suppose at this point, I'm limited to the strength of the carrier.

I'm guessing the PP shafts will give before the carrier. Pretty sweet setup. I'm not a fan of the Lockrite either.

Fix your sig.

 

[Poser]

Interesting. It would stand to reason that a full spool may fit then?

It very well may work, however, what is your remedy for the c-clips used with the semi-float Land Cruiser rear axle?

 

[bsevans]

not surprised it's a close fit. The most common locker for the 40 in the 70's was a 12bolt
gov-loc. Very minor machining. Mainly had to slot the ring gear hole a tiny bit to match the bolt circle of the cruiser ring gear

The GM gov-loc has to be one of the worst lockers ever designed. There are so many components that make up this locker. Once they start to wear this locker is a time bomb. The custom differential shop I use here in Tucson has pumpkins on the wall that housed a gov-loc when it let go blowing a hole in the housing. It did not take a lot of convincing to replace the gov-loc in the rear axle of my GM vehicle.

 

[fromme]

It very well may work, however, what is your remedy for the c-clips used with the semi-float Land Cruiser rear axle?

I suppose that would be impossible without doing a custom external c-clip elimantor.

 

[lcwizard]

I wonder if the 12 bolt c-clips would fit a cruiser axle. Either way it doesn't look as if you had a ton of grinding. By the way cruiser c-clip are available in different thicknesses

 

[fromme]

I could use a thicker c-clip as there's still more shaft end play than I'd like. But i needed to get it back together. Next time I have the cover off i'll try a thin one on the left and a thicker one on the right.
Know where to source these c-clips?

And no, it didn't need much grinding so it's not really an issue.

But to be clear you will have grind any c-clip with this set up using cruiser shafts. The 12 bolt shafts are either 'longer' at the end or the shafts can be pushed in farther so the c-clips don't have to slide through that cut out on the side gears; the recess on the shaft clears it and clips can be simply slid on. That cut out is strictly for the center blocks but its the only way to get the clip on a cruiser shaft.

 

[lcwizard]

Try ARB they include an assortment of thicknesses in their semi float air lockers, otherwise Toyota...
if they haven't discontinued them too

 

[HunterMcC1]

I have run a Richmond mini-spool in 40 with 40" boggers for 6 years and never had and issue... they come out pretty easily too... nice write-up!

 

[bustanutley]

It very well may work, however, what is your remedy for the c-clips used with the semi-float Land Cruiser rear axle?

It does work, but, we use the 35spline verity with shafts that have mini truck semi float bearings.