I think the 400/420s great machines but the additional cost of attachments are a turn off for me. I would lean towards the 420 of the two. From WFM:
The John Deere 400 series Garden Tractors
The year 1975 brought many changes to the John Deere garden tractor line. Engines were now enclosed and rubber mounted. The 100 series that had been the staple of the line since the beginning was replaced by the 200 series tractors, the 140 was replaced by the new 300. Styling was changed to more closely reflect the styling on the full size farm tractors, and headlights were integrated into this styling. OSHA put greater emphasis on operator safety. And horsepower was up across the board. No where was this more prevalent than in the new 400.
Imagine your surprise, visiting your friendly Weekend Freedom Machines dealer to buy a hydrostatic filter for your less than a year old 140, when you see the new 400. If the new styling wasn’t enough of a shock how about the sheer size of it! And the features, including POWER STEERING! For 1975 the 400 introduced the following new features:
- Twin cylinder air-cooled 19.9 horsepower Kohler KQ532 with oil filter.
- Two speed hydrostatic transaxle.
- A rear mounted 4.5-gallon fuel tank.
- Power Assisted steering.
- Three spools of hydraulics, 2 remote and 1 for the rockshaft.
- PTO driven mower deck and snowthrower.
- A 60” mower deck.
- Rear PTO drive for towed and three point attachments (optional).
- Rockshaft installed Category “0” three point hitch (optional).
How much bigger was a 400 than a 140? The wheelbase was six inches longer, the overall length was 8 inches greater, and the track was seven inches wider than a 140 with its rear wheels set out. Not only that, but it was 250 pounds heavier. The front tires were the same size as the rear tires on last years Model 70 Lawn Tractor. It was a tractor in the world of lawn mowers, and its new 60” deck could eat an acre every 30 minutes. The impact at the time must have been similar to when the 5010 was introduced.
Of course, a tractor this size needed specially sized attachments. Allied equipment suppliers were once again quick to provide attachments for the commercial user including front loaders and rear backhoes, trenchers, 3-point mounted flail mowers and rear post hole diggers. Deere had a full array of factory attachments ready for the introduction of the 400. All were configured to make the most of a tractor this size. Factory offered attachments are as follows:
- A 60” mowing deck (shaft driven)
- # 50 Snowthower (shaft driven)
- #56 Front Blade with Hydraulic lift and angle
- # 35 Rotary Tiller, operated off of the optional rear PTO and 3-point hitch.
- #15 Plow with a 12” bottom.
- #20 Front Mounted Loader.
Deere obviously introduced the 400 to take on all the competition, which at that time was primarily Bolen’s HT-20. But with power steering as standard, and the backing of Deere’s parts network, it took the wind out of the competition’s sails. It took International 5 years to match it with the Cub Cadet 982. It is considered by many to be the first “Super Garden Tractor”. And the number of these tractors still being used today is a testament to the people that built them.
The Model 420 and 430
For eight years, the 400 ruled as monarch over the Deere Lawn and Garden line. Thankfully it did not suffer the same growing pains that the 300 series did. In 1983, Deere replaced the 400 with an all-new design; the 420. It was quieter, stronger, and had a few more features than the 400 it replaced. As with the 400, it was an immediate success. Features included:
- Two-cylinder 20 horsepower Onan B48G air cooled engine with cast iron cylinder liners
- First use of annunciator lights incorporated into dash panel.
- Electromagnetic clutch for both front and rear PTO.
- Redesigned fender deck resulting in a more "squared off" appearance with greater operator protection and comfort and a rear mounted 6.5-gallon fuel tank.
- Redesigned front axle to allow more weight bearing capacity. Replaceable spindle bushings.
- Transaxle manufactured by Tecumseh, with a Hydraulic oil cooler, two speeds, and differential lock
- True hydrostatic power steering. A first on a Lawn and Garden tractor.
- A reserve fuel tank that allowed 15-30 minutes extra operating time.
- Three spools of remote hydraulics.
The greatest contributions that the 420 brought to the table were the hydrostatic power steering and the new Onan engine. The steering allowed a turning radius of 26 inches, the same as a 318! With the 60-inch deck, three point turns were all but eliminated. The Onan engine had a long resume of commercial and industrial applications. It was quieter, and had greater torque rise than the Kohler it replaced. By this time, more compact tractors had reached the marketplace, with Deere entering it in 1979 with the 750 and the 850. These Yanmar-sourced diesels helped to fill the gap between the garden tractor line and the farm tractor line. As such, the new 420 was slightly lighter than the 400 it replaced. Emphasis was placed on operator comfort and convenience. Deere offered the following attachments:
- 50- or 60-inch mower deck with shaft drive
- 50- or 60-inch rear grooming mower
- 48-inch rotary tiller
- 54-inch front blade
- 46-inch front snow thrower
- 47-inch 2 stage snow blower
- #20 plow
- #44 front loader
In 1984, Deere introduced the 430, Deere’s first tractor to combine a diesel engine with hydrostatic drive and power steering. The 430 utilized a Yanmar 3-cylinder water-cooled diesel, and all of the features previously found on a 420. Turning radius and attachments remained the same, but weight was up; 1170 pounds. The heaviest, strongest John Deere garden tractor ever. The 420 and the 430 stayed in the garden tractor line until 1992, with the introduction of the 425 series. Many consider these to be the best that John Deere ever built, perhaps the best in the industry. No other garden tractor combined all of the features and stamina, convenience and versatility that epitomized the 400 series.