TH400 Shift Kit 1965-1990 ACA-1800 OEM

Overview

Aftermarket shift kit for TH400 automatic transmissions, 1965-1990 model years. Direct-fit replacement built to OEM specifications. Trusted in shops nationwide for TH400 rebuilds and repairs.

Common Symptoms This Part Solves

Soft, mushy, or sloppy shifts; slipping between gears under load; clutch wear from cushioned engagement. A shift kit firms up shifts to OEM-correct or performance specs and reduces clutch slippage.

Specifications

• Transmission: TH400
• Part Type: Shift Kit
• Brand: Aftermarket
• Part Number: ACA-1800
• Year Range: 1965-1990
• Quality Level: Premium Aftermarket

Fitment

Fits GM, Chevrolet, GMC, Cadillac vehicles equipped with the TH400 automatic transmission, 1965-1990 model years. Cross-check your transmission ID tag and existing part number before ordering. Contact us for fitment verification on borderline year-model combinations.

Quality & Service

Free shipping on orders over $99. Same-day shipping on in-stock parts. All parts are sourced through verified suppliers and inspected before fulfillment. Questions about fitment or installation? Contact our team — we know TH400 transmissions inside and out.