I don't know much about it but it shows up as an attachment in my 650B/660B (58K-up) tractor parts manual. Apparently it provides hydraulic fore and aft movement of the scraper hitch thus changing the axle loading. Looks to be something available in the early 70's as it is not described in my earlier 666 77F tractor, 20G scraper Service Manual.
Just occurred to me that as an attachment it wouldn't be described in the regular service manual. This particular one is a "5D7060 Traction Control Unit" but I couldn't find any info about it other than the parts diagram.
Place where I worked many years ago had 3 mid '60's build 630B's that were fitted with it. The front wheels could be raised quite a distance off the ground, I used to have a photo of 2 of them parked nose to nose with the front wheels raised up....long since lost unfortunately.
Rusted , thank you very much . This is the right solution . A pity you don't have the picture . But you can make another one by buying 2 666 scale models and putting them in the right position . Have a nice day .
I remember reading about this in service magazines in the early'70's and my understanding was that it was fitted on two axle tractors and lifted the front end to transfer the whole tractor weight on to the drive axle, the positioning of the bottom hitch pins below and forward of the drive axle was designed to keep the front wheels on the ground for best steering but lifting the front end and standing on the diff lock pedal could get the machine out of a sticky patch.
I remember reading about this in service magazines in the early'70's and my understanding was that it was fitted on two axle tractors and lifted the front end to transfer the whole tractor weight on to the drive axle, the positioning of the bottom hitch pins below and forward of the drive axle was designed to keep the front wheels on the ground for best steering but lifting the front end and standing on the diff lock pedal could get the machine out of a sticky patch.
Back in 1966, there was 9 Triple 6 scrapers working on I-29 north of St Joseph, Mo. 6 were equipped with this attachment. While sitting, when the control valve was screwed down, it would only lift some weight off of the front wheel, not off the ground. However under a pull, those front wheels would come right off the ground and thus added weight to the drive wheels. Operator had to be carefull if one drive wheel would be on soft dirt, the opposite wheel would try to jacknife the tractor. As I recall, those machines did not have differential locks. With two D9 G's pushing, they could pick up a load in short order in that Loes soil. In places, they cut the banks straight up and down. Still standing today with out slipping. If they had cut the banks on a slope, it would wash badly. As a feild mechanic, I would ride standing behind the dash where I could hear the exhaust real well. Under a load, that ol turbocharger would blow and the exhaust would sound like it was a gas turbine. Those were the "Glory Days" of moving large amounts of dirt. They also used large twin engine Hyster compactors. High powered D3304's powering twin D6 C Power shift transmissions,also equipped with small dozer blades. Bill Walter
Thank you guys for the stories and the drawing . We may be sure this construction is something we don't come across every day .
The Netherlands , johan7
D7 3T
D4 7U
no.4 grader