Grind/Rattle Noise from Transaxle in Park and Neutral After Extended Cold Soak Following Case Cover Replacement or Other Internal Transaxle Overhaul (Replace Case Cover Assm.,Torque Converter, Filter)

This bulletin is being revised with updated Correction and Part information. Please discard Corporate Bulletin Number 04-07-30-032 (Section 07 - Transmission/Transaxle).

After a VT25E transaxle overhaul or case cover replacement (performed prior to the release of polyacrylate [PA] sealant, P/N 24233365), some customers may comment on a prolonged grinding or rattling noise that occurs during the initial start of the vehicle, immediately following an extended cold soak, or after the vehicle has not been driven or operated for several hours. The grind/rattle noise may be present in Park and Neutral and may last between one to ten minutes in duration, or until the internal transaxle fluid temperature reaches or nears normal operating temperature of 82°C (180°F).

Following a VT25E overhaul or case cover replacement using the old anaerobic sealant (P/N 22722716), excessive sealant inside the transaxle may cause oil pump filter restrictions, resulting in various performance issues and/or a prolonged grind rattle noise during initial start-up.

Evaluate the vehicle for the grind/rattle noise condition. If noise type and duration match the symptoms for this condition, thoroughly flush the transaxle oil cooler, replace the case cover assembly, torque converter, filter and transaxle oil cooler lines if necessary.

1. Verify the customer concern of prolonged grind/rattle from the VT25E transaxle during initial cold start.
2. Observe the type and duration of noise experienced.

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A grind/rattle noise that is only present for 1-3 seconds following initial engine start-up is considered normal, due to a short purge time necessary to remove any air in the inlet side of the oil pump. No repair is authorized for this type of noise and/or duration of noise following initial engine start up.

•	Noise not present during initial engine start-up, but is only noticeable during low speed driving maneuvers. For this type of noise condition, refer to Corporate Bulletin Number 03-07-30-051A.

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Noise is present between one to ten minutes in duration, in Park and Neutral and will gradually dissipate as the transaxle fluid temperature reaches or nears normal operating temperature. Proceed with replacement of the Case Cover Assembly, Torque Converter and Filter. Flush the cooler lines using the flushing procedures in Corporate Bulletin Number 03-07-30-022.

Important: Vehicles built with previous design transaxle oil cooler lines containing the oil bypass valve will need to have the transaxle oil cooler lines replaced. For vehicles built with previous design transaxle oil cooler lines, replace with new design transaxle oil cooler line, P/N  22724408. If no bypass valve is present, the transaxle oil cooler lines can be flushed with cooler and re-used.

For vehicles repaired under warranty, use: