MerCruiser Sterndrive Driveshaft 45-42634 Alpha One Gen 1 MR Lower Unit Gearcase
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- MerCruiser Lower Unit Drive Shaft Equivalent to 45-42634 used in all MerCruiser MR & Alpha One - Gen I lower units 1983-1990 <<<---Please make sure that the one you are replacing does not have a pre-load pin****
- If you are looking for one with a preload pin (1970-1982), please contact me and I should be able to help.
- Very little / Normal wear on the splines.
- I left the bearing on here, it should be good, but you will want to check it before installation and replace if necessary. This listing is primarily focused toward the drive-shaft itself. For your own piece of mind I would replace the bearing, but this is ultimately up to your discretion.
In a nutshell
- Used on all subsequent MR & Alpha One Gen I drives 1983-1990.
- In short, it replaces all driveshafts that did not have a preload pin.
They used the same Alpha One lower gearcase with all of the engines, as the upper gear case was responsible for the gear ratio.
They used the same lower gearcase with all of the engines 1983-1990 so your particular engine is not a factor here so this basically covers most (120hp 140hp 4cyl 165hp 6cyl 170hp 305 350 470 260hp 2.5L 3.0L 4.1L 3.7L 3.8L 4.3L V6 205hp 185hp 5.0L 5.7L V8 etc...
- Same as Sierra 18-2180
Other Parts Included as pictured
- Retainer 11-42632 / 82519 1 (GLM 23200)
- Race from bearing 31-36387A1 (Bearing is still on the shaft)
- Purchase with confidence!
1983 1984 1985 1986 1987 1988 1989 1990