Well, since I got a new camera for Christmas and I've been trying to document my preparations for Sno*Drift so far, I figured that I might as well post up some of the workings.
This is probably the single most expensive and time consuming improvement of all my preparation.
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I would be a lot further in it's installation but I got strep throat just before Christmas so I ended up not making any progress toward the end of last year and this is how the car looked for about a month.
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Transmission in the car
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Transmission out of the car
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Immediately after I took that picture my apartment manager drove by. Oops, busted. It's a good thing she didn't see where it ended up next.
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My kitchen table has more or less turned into a work bench, collecting various rally related items. The nuts on the ends of the primary and secondary shafts in the picture above ended up being the bane of the case split. Of course the shafts are on bearings so if you put a wrench on there it just spins the shaft. This required the nuts to be unstaked then hit with an impact wrench.
We had to drill the stake off of one of the nuts so that meant a trip to the dealer (since the auto parts stores don't sell those nuts) and if I had to order one, I might as well order both. They were about $20/each.
I finally got around to reading part of the Mazda3 build thread on specialstage.com which has the same differential. Apparently the trick to getting the nuts off is to shift the transmission into 1st or 2nd, then remove the roll pin from the 5th/Reverse shift fork (the exposed shift fork in the picture above) and manually shift the the fork into 5th jamming the transmission since it's in 2 gears at once.
Here is where I would show the break down pictures but I forgot my camera when I brought my transmission to my friend's house. After getting the lock nuts off of the primary and secondary shafts, the transmission actually came apart really easily. Since I was only working on the differential, teardown was pretty limited. The gearsets had to be removed because they were in the way of the ring gear but they just slid out.
The ring gear removal was a bit more problematic. The ring gear is riveted onto the differential so all of the rivets had to be drilled out. The rivet material was pretty soft so they came out fairly easily. Then we found out that the ring gear is pressed onto the diff housing. With a little heat, that came off pretty easily too.
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New diff w/ the ring gear
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The next hangup that occured was the fact that the ring gear holes were too small for the attachment bolts to fit through. The gear appears to be made from unobtanium and ruined the drill bit we tried to widen the holes with. This is going to have to go to a machine shop where they can hit it with carbide or something.
The next order of business was to remove the speedometer gear from the old diff and put it on the new one. Again, easier said than done.
We had to make a few of our own tools
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In the end, we were unable to pull that bearing off and resorted to this
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So that's as far as the build is. Advance sold me the wrong bearings so I'm waiting for the right bearings to come in along with the primary and secondary shaft nuts and the machine shops to open so I can go get my ring gear cut.
Paul
The Paul Donlin Experience
Driver, Owner, The Experience
This is probably the single most expensive and time consuming improvement of all my preparation.
I would be a lot further in it's installation but I got strep throat just before Christmas so I ended up not making any progress toward the end of last year and this is how the car looked for about a month.
Transmission in the car
Transmission out of the car
Immediately after I took that picture my apartment manager drove by. Oops, busted. It's a good thing she didn't see where it ended up next.
My kitchen table has more or less turned into a work bench, collecting various rally related items. The nuts on the ends of the primary and secondary shafts in the picture above ended up being the bane of the case split. Of course the shafts are on bearings so if you put a wrench on there it just spins the shaft. This required the nuts to be unstaked then hit with an impact wrench.
We had to drill the stake off of one of the nuts so that meant a trip to the dealer (since the auto parts stores don't sell those nuts) and if I had to order one, I might as well order both. They were about $20/each.
I finally got around to reading part of the Mazda3 build thread on specialstage.com which has the same differential. Apparently the trick to getting the nuts off is to shift the transmission into 1st or 2nd, then remove the roll pin from the 5th/Reverse shift fork (the exposed shift fork in the picture above) and manually shift the the fork into 5th jamming the transmission since it's in 2 gears at once.
Here is where I would show the break down pictures but I forgot my camera when I brought my transmission to my friend's house. After getting the lock nuts off of the primary and secondary shafts, the transmission actually came apart really easily. Since I was only working on the differential, teardown was pretty limited. The gearsets had to be removed because they were in the way of the ring gear but they just slid out.
The ring gear removal was a bit more problematic. The ring gear is riveted onto the differential so all of the rivets had to be drilled out. The rivet material was pretty soft so they came out fairly easily. Then we found out that the ring gear is pressed onto the diff housing. With a little heat, that came off pretty easily too.
New diff w/ the ring gear
The next hangup that occured was the fact that the ring gear holes were too small for the attachment bolts to fit through. The gear appears to be made from unobtanium and ruined the drill bit we tried to widen the holes with. This is going to have to go to a machine shop where they can hit it with carbide or something.
The next order of business was to remove the speedometer gear from the old diff and put it on the new one. Again, easier said than done.
We had to make a few of our own tools
In the end, we were unable to pull that bearing off and resorted to this
So that's as far as the build is. Advance sold me the wrong bearings so I'm waiting for the right bearings to come in along with the primary and secondary shaft nuts and the machine shops to open so I can go get my ring gear cut.
Paul
The Paul Donlin Experience
Driver, Owner, The Experience
