JASPER, IN - Jasper Engines & Transmissions is making an update to the turbine half of the General Motors M 4L80E converter and has also recognized a high-wear item on the rear-wheel drive Chrysler overdrive transmission cases.
The update centers around a common problem where the fins pull out of the turbine, according to Craig Leuck, Jasper transmission division manager. "Every one of the fins are bent over and staked to the inside, and the outside, of the 4L80E turbine itself," said Leuck. "Over time, and vehicle use, the fins will get loose, pull themselves out of the turbine, and make metal to metal contact with the pump half of the converter."
Jasper brazes 100-percent of the turbine fins with a paste and a heat treating process. "Every one of the fins is brazed on the inside, and the outside, of the converter," added Leuck. "This ensures the fins stay in place, and there's no metal-to-metal contact."
Jasper also recognized a high-wear item on the rear-wheel drive Chrysler overdrive transmission cases.
"When cores come in for remanufacturing, Jasper has found RWD Chrysler overdrive transmission cases with an enlarged hole for the dipstick tube," said Leuck. "The hole becomes enlarged over time because the dipstick tube will move around inside the case."
Jasper will use a special reaming tool to oversize the diameter of the dipstick tube hole. A brass bushing is then driven into the case and held in place with sealant. "This update is made before the assembled transmission undergoes submersion testing in water, and checked for leaks," added Leuck.