Production run
Toro 20339 partsSerial 315000001–315999999
Belt 38990, gear 59502, cover 490-2012 and fuel treatment 130-2393 all start being listed here. Of the nine 20339 listings, all open, the one below has none.
At your boundary
What changes at the edges of this run
Drive belts
—→38990at 315000001
22 Inch Drive Belt for Recycler Mower 38990 is among this range’s accessories and is not among those of the listing directly below.
The two listings are consecutive, so this serial is where the belt starts being offered. For a 314-series machine Toro lists no belt at all.
Covers and storage
—→490-2012at 315000001
Smart Stow Cover 490-2012 appears here and is absent from the 314 listing.
Same edge, and it is one of four parts arriving on it. Four unrelated items on one serial reads to us like a listing being extended, though Toro states no cause and that reading is ours.
In detail
This production run
Four of the parts this site holds start being listed for the 20339 at this serial, and none of them stops afterwards.
Toro names, for this range, the 22 Inch Drive Belt for Recycler Mower 38990, the Replacement Front Wheel Drive Internal Gear 59502, the Smart Stow Cover 490-2012, and Premium Fuel Treatment (0.5 oz.) 130-2393. The listing directly below — 314000001–314999999, the earliest Toro publishes for this model number — names none of the four as accessories of their own.
Because those two runs are consecutive, the serial is the edge itself rather than a bracket around it. All nine of the listings Toro publishes for the 20339 have been read, which is what makes that claim available.
The engine maintenance kit is not part of this boundary. It is 20234 here, as it is in the run below and the run above, and it changes to 130-8148 at 400000000 — six runs further on, with its own page.
Four unrelated parts arriving on one serial is worth reading carefully. Our own reading is that a listing was extended rather than a mower redesigned — a belt, a gear, a cover and a fuel treatment have no common cause we can think of. Toro states no cause on any of these pages, so treat that as our inference and not as something the listings say.
Confirmed
What we have recorded for this serial range
We record the part categories this site covers. Toro’s own listing for this range carries other accessories besides.
Engine maintenance kits
Engine Maintenance Kit for Briggs & Stratton Engine 20234
Listed by Toro as Engine Maintenance Kit for Briggs & Stratton Engine on its official parts page for model 20339, serial range 315000001–315999999.
Drive belts
22 Inch Drive Belt for Recycler Mower 38990
Listed by Toro as 22 Inch Drive Belt for Recycler Mower on its official parts page for model 20339, serial range 315000001–315999999.
Wheels and drive gears
Replacement Front Wheel Drive Internal Gear 59502
Listed by Toro as Replacement Front Wheel Drive Internal Gear on its official parts page for model 20339, serial range 315000001–315999999.
Covers and storage
Smart Stow Cover 490-2012
Listed by Toro as Smart Stow Cover on its official parts page for model 20339, serial range 315000001–315999999.
Fuel treatment
Premium Fuel Treatment (0.5 oz.) 130-2393
Listed by Toro as Premium Fuel Treatment (0.5 oz.) on its official parts page for model 20339, serial range 315000001–315999999. This is a fuel treatment rather than a fitted part.
Not listed here
Listed for a neighbouring run, but not this one
Absence from a parts listing is not a statement that a part does not fit. It is the manufacturer not saying.
130-8148 Not verified
Toro does not name Briggs & Stratton EXi Engine Maintenance Kit Replacement (130-8148) among the accessories on its parts page for model 20339, serial range 315000001–315999999.
137-4837P Not verified
Toro does not name Replacement 11 in. Rear High Wheel for Push and Front Wheel Drive Lawn Mowers (137-4837P) among the accessories on its parts page for model 20339, serial range 315000001–315999999.
Every run we opened
Unchanged across the runs we opened
If you are close to the edge
Serial numbers near a boundary
The lower edge is the one to check. A serial below 315000001 falls in a run for which Toro lists no drive belt, no front-wheel gear, no cover and no separate fuel treatment, so a misread digit here changes what this site can tell you rather than changing a part number.
Other runs
Other production runs of the 20339
Toro publishes 9 parts listings for this model number. We have opened 9.
Method
How we established this
We opened all nine of Toro’s parts listings for model 20339, the count taken from the serial-range selector on the listings themselves, and compared the accessories they name within the part categories this site records. The pages carry further accessories we hold no record for — engine oils, grass bags, a striping kit, and fuel products other than 130-2393. This listing also carries an XRef entry to 137-4837 under part number 119-0313 which is not in this site’s dataset; no claim on this page depends on it.
The common mistake: Reading “appears at 315000001” as “was redesigned at 315000001”. What appears is an entry in a catalogue. Whether the part itself is new is not something a parts listing states, and this page does not guess.
Provenance
Sources
Last verified against these sources on August 20, 2026.
- 1
Parts — 22in Recycler Lawn Mower with SmartStow, model 20339, serial range 315000001–315999999
The Toro Company · Primary source · Accessed August 20, 2026
Toro’s official parts listing for this model and serial range, reached from the serial-range selector on the model’s other listings. Within the part categories this site records, its accessory list names 20234, 38990, 59502, 490-2012, and does not name 130-8148, 137-4837P. The page carries further accessories this site holds no record for, among them engine oils, bags and fuel products other than 130-2393.
- 2
Parts — 22in Recycler Lawn Mower with SmartStow, model 20339, serial range 314000001–314999999
The Toro Company · Primary source · Accessed August 20, 2026
Toro’s official parts listing for this model and serial range, reached from the serial-range selector on the model’s other listings. Within the part categories this site records, its accessory list names 20234, and does not name 38990, 59502, 130-8148, 137-4837P, 490-2012. The page carries further accessories this site holds no record for, among them engine oils, bags and fuel products other than 130-2393.
- 3
The Toro Company · Primary source · Accessed August 17, 2026
Lists 20234 (Engine Maintenance Kit for Briggs & Stratton Engine), 38990 (22 Inch Drive Belt for Recycler Mower), 59534P, 59502 and 490-2012. The range selector names eight further serial ranges for this model number.
- 4
The Toro Company · Primary source · Accessed August 17, 2026
Lists 130-8148 in place of 20234, and adds 137-4837P (Replacement 11 in. Rear High Wheel). Still lists 38990 and 59502.