Scion XD/XA/Yaris compatibility

[Justaname]

I hope this is okay. I dont have a yaris BUT I have a scion XA. The scion forums are pretty shy on information for the XA. I want to know if the scion XD transmission with fit in a scion XA or if I can put a yaris transmission in my XA. The XA has the same final gearing as the XB(4.31) so at 70mph the car is at 3500 rpms, very loud and bad gas mileage on the highway. I have seen the thread where someone put a yaris trans in the XD(slightly different final drive in the stock XD 3.94 IIRC or something like that). If its a direct bolt in that could work for me, or if the yaris trans can be bolted in without too much work that would be great too. Anyone here know for sure what can go into what?

[Dodge Aries K]

As far as I'm aware the Scion xA is basically a Toyota Echo/Yaris underneath and mechanically. I wanted to get an xB trans and put it into a Echo I used to have. As far as I saw and thought it SHOULD work but I have no physical proof to back that up.

[Bluevitz-rs]

xA is built on the first gen platform. Not compatible with xD or Yaris.

[CrankyOldMan]

The Echo is also based on a C150 manual gearbox, which is narrower than the C50 from the xD/Yaris/xA/xB. And the xD gearbox is only partially compatible with the Yaris--the differential has incompatible splines and the axles are a different length.

[Justaname]

The Echo is also based on a C150 manual gearbox, which is narrower than the C50 from the xD/Yaris/xA/xB. And the xD gearbox is only partially compatible with the Yaris--the differential has incompatible splines and the axles are a different length.

Yes, but will the XD trans fit in the XA?

[CrankyOldMan]

Apologies, I lost track of the original question. The only guaranteed way I know of to get a different final drive without fitment issues is to change the pinion shaft and ring gear. That requires a full tear down of the gearbox and disassembly of the pinion shaft, or a donor gearbox to swap the internals from. The external mounting points and shift linkage are probably different, so a 1:1 swap probably won't work. Take a look at my transmission teardown gearbox comparison thread for details. If you're reasonably handy with tools and can follow the repair manual, it's not a terribly difficult job. There's a few specialty tools that will make it easier, but the gearbox can be torn down and put back together in a weekend, easily.

I would stay away from the xD gearbox unless you're prepared to mess with drive shaft fitment issues, since you'd be changing out the inboard stubs to get the xD splines, and the length is probably different. There's a recent thread where someone made the swap and it was a big headache trying to find axles that connected the xD gearbox to the Yaris hubs.

Gearbox comparison thread: http://www.yarisworld.com/forums/showthread.php?t=38477