Premature Failure of Mitsubishi Galant Ring Gears

Torque converter rebuilders have been reporting an increase in the number of failed ring gears onMitsubishi Galantconverters. Most of the failed ring gears are found on 2006-2008 vehicles equipped with V6 engines, and the failures seem to occur soon after the vehicle's starter has been replaced.

在环形齿轮故障之前，大多数客户在启动期间报告听到噪音，然后是起动器非接合条件。在大多数车辆中，起动齿圈位于柔性板的外径上;当环形齿轮发生故障时，必须更换柔性板。在大多数三菱阴囊上，齿圈直接安装在转换器上，这使得更难以更换且更昂贵的更换。如果车辆的里程或ATF的外观使其状况transmissionquestionable, replacing the converter and overhauling the transmission may be a better option than simply replacing the converter. If it is a low-mileage vehicle and the ATF appears to be in good condition, it is possible to replace only the ring gear.

Unfortunately, the location of the ring gear on the Galant converters makes it impossible to replace the gear without disassembling the converter. The welds used to secure the ring gear to the cover are too close to the TCC reacting surface to allow the ring gear to be replaced with the converter still assembled.

A ring gear typically can be removed from the converter by machining the welds off on a lathe. On some models of the Galant the ring gear is mounted to the outer diameter of the converter cover. On the 2006-2008 Galant, the ring gear is mounted to the front of the cover directly adjacent to the four mounting pads. The close proximity of the ring gear to the mounting pads makes ring gear removal more difficult. On those converters, a milling machine is a better option than machining the welds off on a lathe. If you are only removing one ring gear, you can secure the cover directly to the bed of the milling machine, see picture.

If you are removing more than one ring gear, you may want to mount your cover to a turntable. To remove the weld, plunge into the weld until the milling bit contacts the ring gear (the ring gear is harder than the weld and has a different feel on the cross feed). Do not force the milling bit into the ring gear. If you do, the bit will quickly become dull.

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Why Did the OEM Ring Gear Fail?

在环形齿轮损坏的原因不是小孩ally clear, all known failures have been in vehicles with aftermarket replacement starters. The OEM replacement starter cost about $160, so customers often elect to go with an aftermarket starter that is about $40 less. In the short run, these customers did save $40, but in the long-run they also had to pay for the R&R of the converter, the cost of the replacement converter and opted to go back to the OEM replacement starters to prevent repeat failures.

Ed Lee is a Sonnax Technical Specialist who writes on issues of interest to torque converter rebuilders. Sonnax supports theTorque Converter Rebuilders Association.