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MTD
Riding Mowers & Tractors

Model # 13A878XS099 Official MTD lawn tractor

Here are the diagrams and repair parts for Official MTD 13A878XS099 lawn tractor, as well as links to manuals and error code tables, if available.

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Owner’s manual
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Model diagram and schematic

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Showing 10 of 456 parts  |
Lawn Tractor 42-in Deck Bagging Blade 942-04308
#30

Mower deck/spindle diagram

Lawn tractor 42-in deck bagging blade

Part #942-04308

Replaced by #942-04308A

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Manufacturer substitution
This part replaces 942-04308. Substitute parts can look different from the original.
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Lawn & Garden Equipment Cotter Pin, 1/4- To 5/16-in 714-04040
Lawn & garden equipment cotter pin, 1/4- to 5/16-in

Part #714-04040

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Lawn & Garden Equipment Hex Flange Nut (replaces 753-05549, 912-0417a) 712-0417A
Lawn & garden equipment hex flange nut (replaces 753-05549, 912-0417a)

Part #712-0417A

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Ace Lawn & Garden Equipment Self-tapping Bolt, 5/16-18 X 3/4-in (replaces 1724491, 1740496, 1909304, 910-1260a, Gw-7101260) 710-1260A
Ace lawn & garden equipment self-tapping bolt, 5/16-18 x 3/4-in (replaces 1724491, 1740496, 1909304, 910-1260a, gw-7101260)

Part #710-1260A

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Lawn Tractor Ground Drive Belt, 2/3 X 90-4/5-in (replaces 754-0467a, 954-0467) 954-0467A
#69

Transmission diagram

Lawn tractor ground drive belt, 2/3 x 90-4/5-in (replaces 754-0467a, 954-0467)

Part #954-0467A

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Lawn Tractor Bearing (replaces 741-04124) 941-04124
#16

Steering diagram

Lawn tractor bearing (replaces 741-04124)

Part #941-04124

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Lawn Tractor Steering Sector Gear 617-04094
#1

Steering diagram

Lawn tractor steering sector gear

Part #617-04094

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Troybilt Lawn Tractor Mandrel Assembly 918-06991
#1

Mower deck/spindle diagram

Troybilt lawn tractor mandrel assembly

Part #918-06991

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Lawn Tractor Steering Shaft 938-05078
#15

Steering diagram

Lawn tractor steering shaft

Part #938-05078

Replaced by #738P07154

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Manufacturer substitution
This part replaces 938-05078. Substitute parts can look different from the original.
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Lawn Tractor Wheel Cap (replaces 731-0484a) 931-0484A
#13

Steering diagram

Lawn tractor wheel cap (replaces 731-0484a)

Part #931-0484A

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Main causes: punctured tire or inner tube, leaky valve stem, damaged wheel rim…

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