My Orders
138-668-0 MTD - Overview
Models starting with 138-668-0
Click on the best match to narrow your results.
- 138-668-000 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-000 (1988) MTD Lawn Tractor (Mtd Lawn Tractor)
- 138-668-002 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-009 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-016 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-019 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-022 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-026 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-029 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-033 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-054 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-057 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-058 MTD Lawn Mower (MTD Lawn Mower Model 138-668-058 (138668058, 138 668 058) Parts)
- 138-668-058NE4146D (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-668-077 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
- 138-668-088 MTD Lawn Mower (MTD Lawn Mower Model 138-668-088 (138668088, 138 668 088) Parts)
- 138-668-098 (1988 -Style 8) MTD Lawn Tractor (Lawn Tractor)
Enter a part description. DIY Heroes keep it simple, eg. "belt" or "pump".
Search filter:
Clear Filter
Your search term must have 3 or more characters.
$6.40
In Stock
Lawn Mower Hex Washer Head Screw
Part #710-0599
This is an original replacement part sourced directly from the manufacturer. The screw is commonly found in yard equipment from Craftsman, such as lawn tractors, snow blowers, and edgers. This part is made of metal, and may be found in various locations in the machine, depending on model. Please be aware that there are different screws...Read more used in the machine. Refer to the parts diagram to be sure of ordering the correct part. You will require a wrench when replacing this item. The screw is sold as an individual replacement part.
Read less
$42.70
Special Order
Control Box-thrott
Part #831-0823A
The Throttle Box Assembly, or the Throttle Assembly, is a kit that includes the housing, handle, and hardware. It is black and constructed of steel and plastic. It can be installed onto the right hand upper handle, using a screwdriver and pliers, and is rated as Medium difficulty to install.
This kit contains the parts that control the ...Read moreamount of the air and fuel entering the engine. When the part breaks (likely due to fatigue) you will no longer be able to control the engine. If nothing happens when you move the handle, that means it has become disconnected. When the part is broken it must be replaced. Check your model number to ensure you are selecting the correct replacement part.
Read less
$10.54
In Stock
Lawn Mower Plastic Flange Bearing
Part #741-0487C
Made of durable silver plastic, this Flange Bearing is an authentic manufacturer-source replacement part for hundreds of models of lawn and garden equipment. It is used to allow a shaft to connect while moving smoothly and freely and is sold individually.
When this part malfunctions, you may notice the shaft becomes very sloppy or comes...Read more disconnected. To complete this repair, you will need a screwdriver, a socket set, and pliers.
Customers rate this repair as Medium difficulty.
Read less
$6.74
In Stock
Wsh, Bell., .34 x .872 x .06
Part #736-0242
Sourced directly from the original manufacturer, this Bell Washer is made of gold-colored metal and is sold individually, not as part of a kit or assembly. It is used to provide spacing between various part assemblies along a shaft.
If you hear a strange noise coming from the shaft area, or you notice the Washer is visibly worn or damag...Read moreed, it will need to be replaced. Refer to your owners manual to determine the exact location of this part.
Customers rate the difficulty of this repair as Medium.
Read less
$10.54
In Stock
Lawn Mower Brake Puck
Part #917-0678
When the brakes are applied, this brake puck presses against the brake disc in your lawn equipment to help slow down or stop it. The brake puck is in the brake assembly, which might be located near the transmission or the wheels of your machine. If you notice that the machine takes longer to stop or that there is a loud scraping or grindi...Read moreng noise when you push down on the brake, your brake puck may have worn out. If it is not replaced, you risk losing braking power, which leads to equipment damage or accidents. Before any repairs, make sure that your machine is turned off and that the spark plug is disconnected. To dissemble the brake assembly and access the brake puck, use pliers or a wrench to remove any bolts or clips holding it in place. With a screwdriver, pry the brake puck out of your machine. Since this genuine OEM part is sold individually, determine the number of pucks your machine needs by consulting your user manual.
Read less
$6.57
In Stock
Washer-lock 5/16
Part #936-0119
This Washer-Lock 5/16 is a silver, metal part that is sold individually and comes direct from the manufacturer. With a 5/16 Inch Interior Diameter and 1/2 Inch Outside Diameter, it is used to prevent the nut from backing off and becoming loose on the pulley shaft, and is attached to the drive belt pulley assembly. You will know if you nee...Read mored this because your owners manual will specify it, or the model number of your machine will correspond with this part. If the part is broken due to fatigue, the shafts will free spin when they should be locked together, and must be replaced.
Read less
$6.76
In Stock
Spring-extension
Part #932-0264
This is a genuine OEM sourced part that is not part of a kit or assembly and is sold individually. This Spring Extension, or Extension Spring, serves a variety of purposes, depending on your model. It is black, made of metal, and may be found in multiple locations on your machine.
This part needs to be replaced when it is worn, weak, dam...Read moreaged, or broken. Depending on its purpose, you may no longer have control of your machine when the spring breaks. You will need pliers to complete this repair.
Customers rate this repair as Easy.
Read less
$49.44
In Stock
Lawn Mower Grease Benalene (8 Oz)
Part #737-0300A
This 8-oz multi-purpose grease is an OEM replacement lubricant formulated for use in gear cases, transmissions, and chain cases on outdoor power equipment. It helps reduce friction and wear in high-load moving parts, supporting smooth operation and extending component life. Supplied in a convenient tube for easy application, it is an idea...Read morel choice for routine maintenance when servicing gearboxes, transaxles, or drive components that require consistent, heavy-duty lubrication.
Read less
$6.40
Special Order
Lawn Mower Air Valve
Part #934-0255
The air valve attaches to the wheel and is made of a durable material. This is a genuine MTD, Ryobi, Yard Machines, Bolens, Troy-Bilt, and Yard Man part sourced directly from the manufacturer for use in chippers, shredders, cultivators, edgers, lawn tractors, snowblowers, and trimmers. Keep in mind that this part is sold individually. Whe...Read moren replacing this item a set of pliers might be required during the installation process. It might wear out over time and will need replacing.
Read less
No Longer Available
Spring-extension
Part #932-0384
This OEM Extension Spring measures .62 x 6.12 inches. It is a silver, metal, individually sold, part. It can be installed with pliers and has been rated Easy to install by customers. (Note: Installation may require a lot of pull force to remove and reattach.)
The spring attaches underneath the tractor on the drive belt idler pully, to t...Read morehe axle support bracket, and is used to apply tension on the drive belt idler pully. If broken or overly stretched, likely due to fatigue, you will lose your forward and reverse drive, as the belt will no longer be able to transmit power. If this happens, the part must be replaced. Refer to your owners manual and model number to ensure you are selecting the correct part.
Read less
$23.80
In Stock
Trimmer Ball Joint
Part #923-3018
This authentic component is specially designed for MTD riding lawn mowers and garden tractors. It is supplied directly from the original equipment manufacturer. The ball joint is an important part of the steering mechanism. Over time it may wear out or get damaged eventually requiring a replacement to keep your unit functioning properly. ...Read morePlease make sure to refer to the appropriate diagrams of your model for the correct application of this part. Keep in mind this high-quality ball joint is made of durable metal with a rubber component and is sold as an individual item. You need a screwdriver and a wrench set to take apart the housing and perform this repair.
Read less
$16.33
In Stock
Cap-push
Part #726-0214
The Push Cap is a black plastic cap which secures to the end of a shaft to prevent injury. It can be installed with a hammer and is rated as "Easy" to install. If the part appears damaged or worn down in a way that could cause injury, it should be replaced. Refer to your make, model and diagrams to check if this is the right part for you.
Watch our pros, then fix it yourself.
See how others fixed this model. Time, tools, difficulty, and steps that lead to victory!
View More