K313 CVT Transmission Bearing Kit, 4-Piece Toyota Corolla

This is the four-bearing set you need on the bench when a Toyota K313 or K310 CVT comes apart. It covers B49-10UR (49 x 87 x 14 mm), B33Z-15UR (33.5 x 76 x 11 mm), B43-8 (43 x 87 x 19.5 mm) and YTM244618AM (24 x 46 x 18 mm) - the pulley shaft and differential support positions that carry belt clamping load every mile the unit runs. Also referenced as YTM244618AM in some parts listings.

The K313 is the belt-drive CVT Toyota put behind the 1.8L in the Corolla and Auris, and the K310 is its close relative. Both units load their pulley shaft bearings hard because the steel push belt has to be squeezed between the primary and secondary pulleys at high clamp pressure. When those bearings start to brinell or the races pit, you get a whine that rises with road speed and does not change when you lift off the throttle, plus metal in the pan and on the magnet. Once the bearing is loose the pulley shafts lose alignment, the belt tracks off center, and the ramp faces start to score.

Replace all four at once. There is no point reusing a bearing on a unit you already have split open - the labor to go back in is the expensive part, not the bearing. Press the old races out of the case and pulley shafts, clean the bores, then drive the new bearings square with a proper driver on the correct race. Set your shim stack and check pulley shaft endplay against spec before you close the case, because the bearing stack height controls it. Fill with genuine Toyota CVT fluid FE or the correct equivalent - a K313 will not tolerate a generic ATF.

Bearings are high-carbon chromium bearing steel. Kit contains one of each of the four bearings listed above. Ships from the USA.