AC 620 with Model 600 Farm Loader
Source: AC Operator's Manual, Model 600 Farm Loader, courtesy of Frank Heizler
In 1972 Allis-Chalmers introduced the 600 series, which actually helped define the now-booming niche of "compact tractors." Larger than a typical garden tractor, styled like a One-Ninety farm tractor, yet still not a stripped down ag or industrial tractor, the 600 series was a huge success. With a 2000 RPM rear PTO and a category-0 3-point hitch, it is a
versatile workhorse that can handle the same type and size attachments as much-larger tractors.
Allis-Chalmers later introduced the 608/610/611 series of small frame lawn tractors, adding "confusion" to the series number, since they have nothing in common with the 616 or 620. This "confusion" continued when the 620 later became the 720 . . .
Still missing is information on the 616 Special, a small-frame lawn tractor with a 16HP twin-cylinder engine.
Check out the new information on 608 and 610 lawn tractors from a 1974 brochure.
Click for a closer view
[Source: AC brochure, Building big ones has made our small ones better, 1974]