Overview
The Omix-Ada 18880.12 is a mainshaft washer for T90 and T150 manual transmissions and is a factory style replacement. It fits 1974-1975 Jeep Cherokee (SJ), 1974-1975 J10 and J20 trucks, the 1967 Jeep Universal, and the Wagoneer (SJ) in the years covered.
The washer also appears in several CJ and Willys entries from 1946 to 1975. Because no thickness or dimensions are given, compare it to the original washer by part number before installing.
Key features
- Factory style replacement mainshaft washer
- Fits T90 and T150 transmissions
- Omix-Ada part number 18880.12 with UPC 804314066383
- Manufacturer fitment list includes SJ, CJ and Willys models
What the mainshaft washer does
A mainshaft washer sits between a gear or hub and a shoulder on the mainshaft, where it sets the small clearance that lets the gear turn freely. If the washer wears thin or its faces are scored, the gear can move too far, which often shows up as clunking when the clutch is released or a notchy feel when shifting into certain gears.
Before fitting a new washer, check the faces it contacts. They should be flat and free of grooves, since a damaged face will wear a new washer quickly. Keep the washers in the order they were removed, and note any spacers that go with them. Clearance is set during reassembly, so check each part’s fit before final installation rather than assuming the old stack is correct.
- Compare the old washer thickness with the new one by hand
- Check both mating faces on the gear and shaft
- Keep the washers and spacers in their original order
- Lubricate the parts with transmission fluid during assembly
Specifications
| Brand | Omix-Ada |
|---|---|
| Part number | 18880.12 |
| UPC | 804314066383 |
| Part type | Mainshaft washer |
| Transmissions | T90 and T150 |
| Style | Factory style replacement |
Vehicle fitment
The manufacturer list includes the 1974–1975 Jeep Cherokee (SJ), the 1974–1975 J10 and J20, the 1967 Jeep Universal, the 1967 and 1971–1975 Wagoneer (SJ) and the CJ3, CJ5, CJ6 and Willys CJ models in their listed years.
Vehicles and years outside these entries are not on the list, including the 1976 and later CJ models. Confirm your vehicle’s year, model and trim before ordering.
What’s included
Count the washers you receive before beginning the installation.