Medium
1-2 hours
Transmission 121-9178
OEM part for: Toro
Part Number: 121-9178
$124.05
In Stock
Ships within 1 business day 
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Product Description ?
- Shaft is Approx. 20.5" Long
- Classification: Part
- Weight: 2.15 lbs.
- Shipping: Ships Worldwide
Frequently Purchased Together ?
Compatibility
This Transmission will fit the following 110 machines. Confirm this part works with your model, and view the detailed model diagrams and repair help we have to offer.
Toro
Show More Compatible ModelsThis item works with the following types of products:
- Lawn Mower Parts
This part replaces obsolete part #: 115-4652
Customer Part Reviews ?
Average Rating (out of 5):
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Excellent service n quick response!!!
Guest -
August 31, 2021
Verified Purchase
Quick repair
This was the fastest repair ever,easy website to navigate and quick delivery. Price was good including shipping. I will definitely use them again. Check them out your self.
Butch from East Have,Ct.
Andrew -
May 9, 2020
Verified Purchase
Git er done
The right part, the right price, the right fast delivery, I'd say it was all right!
Guest -
April 15, 2020
Verified Purchase
the part installed without difficult even though there were slight differences in the way the belt pulley was attached to the diffferential.
My mower is working fine again now. thanks!
Guest -
June 27, 2019
Verified Purchase
Arrived on time and installed easily.
Arrived the shipment within the time promised. Installation was very easy and the lawn mower now works very well. No need to push really hard anymore.
Guest -
November 17, 2020
Verified Purchase
Questions & Answers ?
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Does this fit my product?Questions & Answers for Transmission
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Customer Repair Instructions ?
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part.
Transmission stopped pulling on my Toro personal pace walk behind mower
Alan - April 28, 2016
👍 8 of 9 people found this instruction helpful
Tool Type
Lawn Mower
Difficulty
Medium
Time
1-2 hours
Tools Used
Screwdriver, Socket set, Wrench Set, Spring clip pliers
Found easy to follow repair instructions on U Tube. followed the step by step instructions. Very easy, just took me a little extra time than the experts seeing how I don't do this kind of repairs every day. Replacement parts from Ereplacement parts .com came very quickly and I will certainly use them again.
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The lawn mower was no longer self propelled
Michael - June 27, 2016
👍 4 of 4 people found this instruction helpful
Tool Type
Lawn Mower
Difficulty
Medium
Time
1-2 hours
Tools Used
Pliers, Socket set, Wrench Set, grease gun
1. Figured out how to take the drive transmission out.
a. Removed the handle, plastic and metal shrouds underneath,
b. Removed the drive wheels and metal side plates holding the transmission.
c. Loosened the belt guide at the engine.
d. Removed the drive belt.
e. Removed the transmission from the side plates. Detach from the control cable.
2. Install the new drive belt around the engine pulley, Tighten the belt guide.
3. Do the reverse of the dis-assembly. Grease all rotating parts
4. Start lawn mower and check operation.
a. Removed the handle, plastic and metal shrouds underneath,
b. Removed the drive wheels and metal side plates holding the transmission.
c. Loosened the belt guide at the engine.
d. Removed the drive belt.
e. Removed the transmission from the side plates. Detach from the control cable.
2. Install the new drive belt around the engine pulley, Tighten the belt guide.
3. Do the reverse of the dis-assembly. Grease all rotating parts
4. Start lawn mower and check operation.
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Lost self propelled
Glenn - September 7, 2018
👍 1 of 1 people found this instruction helpful
Tool Type
Lawn Mower
Difficulty
Medium
Time
30-60 minutes
Tools Used
Socket set, Nutdriver
Parts Used
Followed excellent video on YouTube.
Removed blade
Removed belt covers
Removed belt
Removed axle pins
Slid out axle/transmission assembly and replaced it
Removed blade
Removed belt covers
Removed belt
Removed axle pins
Slid out axle/transmission assembly and replaced it
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Mower needed a new transmission
David - July 2, 2018
👍 1 of 1 people found this instruction helpful
Tool Type
Lawn Mower
Difficulty
Medium
Time
30-60 minutes
Tools Used
Pliers, Socket set, Wrench Set, Nutdriver, Adjustable Wrench
Parts Used
I had watched the video on You tube to see the repair actually in action. This helped in the process of the repair
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Transmission failed
L - July 9, 2017
👍 1 of 1 people found this instruction helpful
Tool Type
Lawn Mower
Difficulty
Easy
Time
30-60 minutes
Tools Used
Screwdriver, Pliers, Socket set, Wrench Set
Parts Used
1. Look up on U-Tube how to replace unit followed most of the direction not all of them.
2. After disassembly found that the bushing and bearings on for the axle were bad.
3. When replacing transmission also get the bushing and bearings for the axle
4. Pick up at local shop and replaced both sides
5. The actual work time was about on hour.
2. After disassembly found that the bushing and bearings on for the axle were bad.
3. When replacing transmission also get the bushing and bearings for the axle
4. Pick up at local shop and replaced both sides
5. The actual work time was about on hour.
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Lawn Mower would not self propel
Paul - September 26, 2016
👍 3 of 5 people found this instruction helpful
Tool Type
Lawn Mower
Difficulty
Medium
Time
1-2 hours
Tools Used
Screwdriver, Socket set, Wrench Set, Nutdriver, Adjustable Wrench, Square Head Socket, Snap Ring Pliers
Parts Used
Removed the blade, removed belt cover and pulleys. Removed both belts. Removed rear wheels and the right side axle holder, slid transmission out. Replaced transmission and re-assembled.
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Rear-wheel drive wheel would spin when making a turn (transmission). Rear wheel squeak (bearing).
Ralph - January 20, 2022
Tool Type
Lawn Mower
Difficulty
Medium
Time
1-2 hours
Tools Used
Screwdriver, Socket set, snap ring pliers, putty knife or scraper
Parts Used
1. Remove rear wheels.
2. Remove drive belt covers.
3. Remove one rear wheel support bracket.
4. Remove transmission.
5. Remove bearing from each rear wheel support bracket.
6. Re-assemble in reverse directions.
2. Remove drive belt covers.
3. Remove one rear wheel support bracket.
4. Remove transmission.
5. Remove bearing from each rear wheel support bracket.
6. Re-assemble in reverse directions.
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Self propel would not engage.
William - August 31, 2021
Tool Type
Lawn Mower
Difficulty
Easy
Time
30-60 minutes
Tools Used
Screwdriver, Pliers, Socket set, Wrench Set, Snap Ring pliers.
Followed instructions on the video.
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Transmission grinding
Jeffrey - September 2, 2020
Tool Type
Lawn Mower
Difficulty
Easy
Time
30-60 minutes
Tools Used
Screwdriver, Pliers, Socket set, Adjustable Wrench, snap ring pliers
Disassembled the parts connecting to the transmission taking note where everything went. Removed the transmission and put the new one in. Reassembled the parts connecting tothe transmission. Works like a charm.
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Transmission pulley wore out
JAMES - August 27, 2020
Tool Type
Lawn Mower
Difficulty
Easy
Time
1-2 hours
Tools Used
Socket set, snap ring pliers, Square drive screw bit
Parts Used
Followed Youtube instructions from ereplacement parts.
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OEM stands for Original Equipment Manufacturer and means the part you’re buying is sourced directly from the manufacturer who made your product. At eReplacementParts, we sell only genuine OEM parts, guaranteeing the part you’re purchasing is of better design and of higher quality than aftermarket parts.
Our product descriptions are a combination of data sourced directly from the manufacturers who made your product as well as content researched and curated by our content & customer service teams. This content is edited and reviewed internally before being made public to customers.
Our customer service team are at the ready daily to answer your part and product questions. We have a dedicated staff with decades of collective experience in helping customers just like you purchase parts to repair their products.
All our part reviews are solicited directly from other customers who have purchased this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
Based on data from past customer purchasing behaviors, these parts are most commonly purchased together along with the part you are viewing. These parts may be necessary or helpful to replace to complete your current repair.
All our installation videos are created and produced in collaboration with our in-house repair technician, Mark Sodja, who has helped millions of eReplacementParts customers over the last 13 years repair their products. Mark has years of experience in selling and repairing both commercial and residential products with a specialty in gas-powered equipment.
This data is collected from customers who submitted a repair instruction after replacing this exact part. Customers can rate how easy the repair was to complete and how long it took. We aggregate this data to provide a repair rating that allows customers to quickly determine the difficulty and time needed to perform their own repair.
