It will be Dynashift, not Dyna4.
Dynashift is a four speed synchromesh gearbox with a high and low range [ a proper low and high range box, not a splitter]. This gives eight mechanical gears, shifted by a gear lever, augmented by a close ratio four speed powershift, giving a total of 32 forward and 32 reverse speeds, many overlapping in their mechanical gears. A very very well respected gearbox which was later replaced by the Dyna6 which is a six speed powershift with four synchronised gears but with a robotised change rather than by gear lever, giving 24X24 ratios.
Any pic of inside please? Doesn’t look dear compared to others at the moment. Is it 120hp?Couple of pics
Used to drive a speedshift 5455 then a dyna 4 5455, night and dayI should explain, for those that are unaware, that the range of tractors was split in two, probably to make up for the demise of the Coventry models that were latterly the 4300 series.
The French electronic tractors that were the 6200 series were split into the 5400 series which have the Speedshift transmission. That has an eight speed synchro gearbox with a rather coarse two speed splitter. Later replaced by the Dyna4 [NOT Dynashift]. A second higher specification range, which is based on the same chassis, is called the 6400. This has a plusher quieter cab with far more standard and optional features available and inherited the 6200’s Dynashift transmission, later replaced by the Dyna6.
While Dynashift and Speedshift was discontinued when the Dyna4 and Dyna6 were introduced, both the D4 and D6 continue in production today, although after nearly 15 years of production with only minimal refinement they must be nearing the end of their production life in 2022. The new 8S models may hint at the eventual replacement for these two old transmissions.
Old they may be, but they are still good transmissions and probably now at their peak of refinement.