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New Yamaha 115–130HP 2/4-Stroke (1984–2014) Replacement Lower Unit – Aftermarket – Standard Rotation – Fits 20″ & 25″ Shafts – 3-Year Warranty
Original price was: $1,330.89.$1,199.00Current price is: $1,199.00.
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New Yamaha 75–100HP 2/4-Stroke (1984–2017) Replacement Lower Unit – Aftermarket – Standard Rotation – Fits 20″ & 25″ Shafts – 2.0 & 2.3 Gear Ratios – 18 Spline – 3-Year Warranty
Original price was: $1,330.89.$1,199.00Current price is: $1,199.00.
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Manufacturer Warranty: 3-Year
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Return Policy: 60-day, hassle-free returns
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Description
High-quality aftermarket replacement lower unit for New Yamaha 75–100HP outboards.
Designed to fit a wide range of Yamaha 2-stroke and 4-stroke models from 1984 to 2017.
Available in 2.0:1 and 2.3:1 gear ratios for 20″ and 25″ shaft lengths.
Painted black – can be repainted to match OEM finish.
Specifications
| Feature | Details |
|---|---|
| Horsepower | 75HP to 100HP |
| Stroke Type | 2-Stroke & 4-Stroke |
| Rotation | Standard (Right-Hand) |
| Gear Ratios | 2.0:1 and 2.3:1 (based on model variant) |
| Shaft Lengths | 20″ and 25″ |
| Paint Color | Black (Can be repainted to match original) |
| Fits Models | F75, F80, F90, F100, 90TLR, E75, and more (See model list below) |
| Exclusions | Not compatible with 2016+ Yamaha 4-stroke models ending in “B” |
| Warranty | 3-Year |
| Brand | SEI |
Technical Guide
90-404-A20 (2:1 Ratio / 20″ Shaft / 2 Stroke / RH Rotation) fits the following Yamaha Models:
- 90TLR Series:
- 2009-2005: 90TLR, 90TLRD
- 2004-2002: 90TLRC, 90TLRB, 90TLRA
- 2001-2000: C90TLRZ, 90TLRZ, C90TLRY, 90TLRY
- 1999-1997: C90TLRX, B90TLRX, 90TLRX, C90TLRW, 90TLRW, B90TLRW, C90TLRV, B90TLRV, 90TLRV, C80TLRV
- 1996-1991: 90TLRU, C75TLRU, 90TLRT, C75TLRT, 90TLRS, C75TLRS, 90TLRR, C85TLRR, 90TLRQ, C85TLRQ, 90TLRP, C85TLRP
- E75/P75 Series:
- 2000-1997: E75MLHY, E75MLHX, E75MLHW, E75MLHV, P75TLHX, P75TLHW, P75TLHV
- 85/90ETL Series:
- 1990: 90ETLD, 90ETLDA, CV85ETLD, CV85ELD
- 1989: 90ETLF, CV85ELF
- 1988-1984: 90ETLG, 90ETLH, 90ETLJ, 90ETLK, 90ETLN
90-404-B20F (2.3:1 Ratio / 20″ Shaft / 4-Stroke) replaces the following Yamaha Models:
- Replaces some F75, F80, F90, and F100 Yamaha gear cases on 4-Stroke Engines with 20-inch drive shaft.
- Does not fit 2016-present 4-stroke engine models ending in “B”.
- Color: Black (Can be painted to match).
- Models:
- F75 Series:
- 2017-2012: F75LA
- 2011-2005: F75TLR, F75TLRD
- 2004: F75TLRC
- 2003: F75TLRB
- F80 Series:
- 2003: F80TLRB
- 2002: F80TLRA
- 2001: F80TLRZ
- 2000: F80TLRY
- 1999: F80TLRX
- F90 Series:
- 2017-2012: F90LA
- 2011-2005: F90TLR, F90TLRD
- 2004: F90TLRC
- 2003: F90TLRB
- F100 Series:
- 2003: F100TLRB
- 2002: F100TLRA
- 2001: F100TLRZ
- 2000: F100TLRY
- 1999: F100TLRX
- F75 Series:
90-404-B25F (2.3:1 Ratio / 25″ Shaft / 4-Stroke) replaces the following Yamaha Models:
- Replaces some F80, F90, and F100 Yamaha gear cases on 4-Stroke Engines with 25-inch drive shaft.
- Does not fit 2016-present 4-stroke engine models ending in “B”.
- Color: Black (Can be painted to match).
- Models:
- F80 Series:
- 2000: F80TXRY
- 1999: F80TXRX
- F90 Series:
- 2017-2012: F90XA
- 2011-2006: F90TXR
- 2005: F90TXR, F90TXRD
- F100 Series:
- 2003: F100TXRB
- 2002: F100TXRA
- 2001: F100TXRZ
- 2000: F100TXRY
- 1999: F100TXRX
- F80 Series:
Additional information
| Weight | 85 lbs |
|---|---|
| Dimensions | 23 × 13 × 26 in |
| Ratio/Shaft/Motor |
2.0 Ratio/20" 18 spline/2-Stroke/RH Rotation ,2.3 Ratio/20" 18 Spline/4-Stroke ,2.3 Ratio/25" 18 Spline/4-Stroke |
Reviews (26)
26 reviews for New Yamaha 75–100HP 2/4-Stroke (1984–2017) Replacement Lower Unit – Aftermarket – Standard Rotation – Fits 20″ & 25″ Shafts – 2.0 & 2.3 Gear Ratios – 18 Spline – 3-Year Warranty
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Pamela Gibson –
No special tools needed. Done in a coffee break!
Taylor Hendrix –
The unit’s grease ports are strategically placed for easy maintenance. Installed it in 40 minutes, and performance has been flawless. OEM should take notes!
John Simmons –
No more overheating issues. Runs like new!
Alexander Wood MD –
Why I waited so long? This unit revived my boat. Smooth, reliable, affordable. Don’t hesitate—buy it now!
Edward Smith –
Rugged housing handles storms. Budget-friendly beast!
Darren Wells –
The packaging included foam inserts to prevent shipping damage. Installation was tool-free, and the unit meshes perfectly with my motor. No leaks or noise—highly recommend!
April Watson –
The included torque specs ensured a proper installation. Two months later, the unit performs like new—no noise, no leaks, no regrets. A perfect aftermarket solution!
Emily Lopez –
The packaging included foam inserts to prevent rattling during transit. Installation took 30 minutes, and the unit meshes perfectly with my motor. No vibrations or leaks—extremely impressed!
Emily Parks –
The unit’s grease fittings made maintenance a breeze. Installation took 40 minutes, and performance has been flawless through 15 hours of runtime. OEM should take notes!
Megan Gonzales –
I’ve used this in both freshwater and salt—zero issues. The stainless steel components stay pristine, and the shifts are crisp. A reliable, affordable solution!
Robin Washington –
Mounted yesterday—handled a full day on the water flawlessly.
Amber Le –
Survived saltwater testing—zero corrosion. Solid engineering!
Mr. Nathan Hernandez –
Perfect for DIYers. Saved $$$ on mechanic fees.
Veronica Cox –
The customer team replied to my midnight query in minutes! The unit is quiet, durable, and leak-proof. A standout in aftermarket parts—highly recommend!
Anne Thornton –
Tested this in icy lakes and tropical waters—no issues. The stainless steel gears handle temperature swings effortlessly, and the shifts stay precise. A four-season workhorse!
Aaron Jackson Jr. –
Everything arrived securely packaged with all hardware included. Installation was a breeze—no missing parts or confusing steps. After two months of heavy use, it still runs like new. Worth every penny!
Johnny Greene –
This unit survived a month-long expedition in Alaskan waters. No corrosion, no leaks, and shifts are as smooth as day one. OEM engineers should take notes!
Danielle May –
Reduced vibration by 90%. Feels factory-new!
Carrie Jones –
Great support—quiet and durable. Standout product!
James Watts –
The unit’s powder-coated finish resists chips and scratches. Installation took 35 minutes, and performance is flawless. Why spend more on overpriced OEM parts?
Andrea Stephens –
I’ve tested this unit in saltwater for three weeks, and there’s no sign of corrosion. The gears engage smoothly, and it’s noticeably quieter than my old OEM part. Highly recommend for marine use!
Kimberly Morris –
Not a single leak. Performs like it’s brand new.
Kimberly Patterson –
Direct replacement—no modifications needed. Works perfectly!
Eric Calhoun –
This unit saved my boating season. Installed in under an hour, it’s outperformed my old OEM part with smoother shifts and better fuel efficiency. Worth every cent!
Jamie Vaughn –
Pre-greased fittings saved me 30 minutes of messy work. Installed solo, and it’s been flawless through 50 hours of runtime. DIYers, this is your holy grail!
Shannon Jacobs –
Installed this on a 2005 motor—fit like a glove. Smooth engagement, no vibrations, and saved $700. Vintage boaters, this is your fix!