It's finally time to get our transmission installed and finish up this project so we can go out and test it! First we have to prepare the Yaris chassis to accept this C60 hybrid, and that means many rounds of test fitting. I mentioned in Part 3 to use the empty fully assembled C60 case to do all of your testing, this means bolting it to the engine and installing the driver side mount while making the marks where you need more clearance. I tried using a huge hammer and also a pneumatic hammer to no avail, I had to get out the grinder and cut metal away to make enough room for the 6 speed.
You can see in the photo above exactly what I had to do to make enough room for the C60. The straight forward instruction here is to make a 8" long cut 1" back from the bottom edge along the under side of the frame rail. You then make a 2" cut upward on each end of the cut, and commence hammering to bend the metal inside the frame rail until it mates up to the edge of the lower cut. Now you need to weld all of these openings up, then grind it down smoothly again and apply some paint to prevent corrosion. Huge thanks to my buddies Mike and Jake for helping out with this part of the project, without their help I would have to pay someone to weld this up for me.
Now its time to install the transmission. The trick I use is to support the engine with a jack stand, put the transmission on a small stool and slide them up close. I then use a chain to hoist up the back of the transmission case until the gap between the engine and transmission is even all the way around. Now you just wiggle the transmission trying to line up the dowel pins, if you're struggling try putting the transmission in gear then turn the engine crank 1mm.
Once the transmission slides into place, install all of the bell housing bolts and the driver side mount. Now you can reinstall everything how it was with the C50, except the axles. The C50 shift linkage, shifter cables, and shifter cage seems to work fine so far, but I'll update as time goes by. So now lets look at the axle situation. I already tried my original 23 spline Yaris axles and they don't fit in the C60 differential, so with Sams help we found some axle spline references online. Thanks Sam!
You can see here that the Yaris has 26 splines at the hubs, and thats good since so does the Celica. The problem is there is no support bearing on the passenger side for the Yaris. When I was comparing my Celica and xD transmission internals, I noticed the differentials had the exact same measurements. So on a hunch I compared the xD axles here as well, you can see that the Xd and the Celica differentials take the same 20 spline axle. I already knew the xD has the correct 26 spline hub from our very first 2zr-swap project with Taylor, so I'm not concerned about the length difference. Now that is how you find axles for a custom project!
In the pictures above you can see the spline area differences between the two axles. The part of the shaft with the splines that slides into the differential only differs about 1mm in diameter between the 2 axles, but the seal surface has a 2mm difference. So at this point I would recommend a set of Celica OR xD axle seals to go with these axles, until I can compare the 2 seals and take measurements. Again, I got lucky that I used a xD transmission case so I don't have to change anything, just lube up the splines and seals and install.
The passenger side axle fit perfectly, but the driver side seemed a bit short. I don't believe its going to be an issue since I have all xD components in this car, but I will report back if anything doesn't seem right. Now that the axles are in its time to fill the trans with your choice of 75W90 gear oil through the standard fill hole first, then top off using the 6th gear fill hole just to be sure. Look around for any leaks and double check the axle nuts and ball joint fasteners. Lower the car on the ground and fill the coolant, reconnect the battery, and verify everything else on the car has been torqued down(wheels!) This next step is super important so pay attention:
Install the 6 speed shift knob! haha. Now you're ready to fire up the car and test the transmission with the wheels off the ground. Next you can go on a road test around the block, check for leaks or noises again. Try to circle around an area you know just in case at first, then once you're confident you can go further.
So far the car feels awesome, but Ive only driven it around the block a few times. Keep and eye on my YouTube channel for the release of my "6 speed Yaris first drive and impressions" video, Thanks for the support!
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