Bewick:
I was a great believer in the improvement that the Eaton axle made to the performance of the motor
The logic goes along the lines why use a gearbox when we can ( try to ) use the diff to do its job.
The fact that they went to all the trouble of making 13, 16, and 18 speed gearboxes and you probably won’t find anything made with a silly two speed axle now answers the question.An ‘improvement’ it ain’t it’s just illogical thinking.
I don’t follow a logic which says that the 2 speed axle was illogical. Eaton even made a 3 speed axle although AFIK it was never available in the uK. I accept that particularly with an overdrive gearbox one ratio is more or less wasted , but the same is so with a splitter box or even some range change boxes with a splitter for the high range. In the '60s and early ‘70s the more or less standard tractor unit wheelbase was 9’ 6" although some models were even shorter. Propshaft angle is a necessary consideration for a chassis that short, a factor helped by the two speed axle allowing an increase in ratios form the more or less standard 6 but without an increase in gearbox length. The splitter boxes of the time were could be troublesome far more so than the two speed axle itself , some gained an unwanted reputation. Even the fabled Fuller gearbox was not exempt from significant issues with its range change and it subsequent development twin splitter was the subject of major modifications. It and the Spicer could easily be damaged by incorrect assembly, both were a trap for the unwary.
The Fuller gained popularity for two main reasons : it was compact and it offered a model capable of accepting the torque output of the more powerful engines coming on stream; something which David Brown could not match. This influenced the more conservative hauliers in their purchasing decisions along with the increasing ability to poach fitters with experience of Fuller overhaul.
One might add that the flexibility and resilience of a Fuller 'box surpassed the ZF AK-80 and DB boxes. ZF & DB boxes were fine but required very precise handling. You could be tired at the end of a long working day with a Fuller and still get it right [Funnily enough, brilliant though the Eaton Twin-Splitter was, you could still get caught out when tired and drifting…]! Just my twopenny-worth!
cav551:
I don’t follow a logic which says that the 2 speed axle was illogical. Eaton even made a 3 speed axle although AFIK it was never available in the uK. I accept that particularly with an overdrive gearbox one ratio is more or less wasted , but the same is so with a splitter box or even some range change boxes with a splitter for the high range. In the '60s and early ‘70s the more or less standard tractor unit wheelbase was 9’ 6" although some models were even shorter. Propshaft angle is a necessary consideration for a chassis that short, a factor helped by the two speed axle allowing an increase in ratios form the more or less standard 6 but without an increase in gearbox length. The splitter boxes of the time were could be troublesome far more so than the two speed axle itself , some gained an unwanted reputation. Even the fabled Fuller gearbox was not exempt from significant issues with its range change and it subsequent development twin splitter was the subject of major modifications. It and the Spicer could easily be damaged by incorrect assembly, both were a trap for the unwary.
The Fuller gained popularity for two main reasons : it was compact and it offered a model capable of accepting the torque output of the more powerful engines coming on stream; something which David Brown could not match. This influenced the more conservative hauliers in their purchasing decisions along with the increasing ability to poach fitters with experience of Fuller overhaul.
The fact remains that the idea of minimising gearbox design and development in favour of multi speed diffs didn’t take off in everything from cars to top weight trucks to date.
Why was that assuming that the latter was the logical solution.Including in the car world at least some manufacturers bolting the gearbox to the diff not the engine.
dave docwra:
Some years ago I worked with a company who ran Seddon rigids with the 6354T engines & the working two speed axle made a massive difference compared to the failed ones which had been wound into high.
I always found some drivers could use them and others just left them in high to avoid the jangling from the back end.
Dave…
That always bothered me, I felt as a fitter that the grating of gears when ‘split shifting’ must be causing damage. However a former test driver told me to make the main change on the box itself and then, just before releasing the clutch pedal, operate the two speed and it will change with no noise, make the change when in neutral…it took a little practice and it actually worked! I found the electric shifts better than the cable operated vacuum ones though, and then you had BMC’s etc where 4th high was actually a higher gear than 5th low which could catch you out the first time! If you went 4th low/5th low/4th high and then 5th high all was well.
Pete.
Not sure if it was the Right or wrong way to use it, I would move the switch then ease off the throttle pedal to allow a smooth change.
Dave…
I always done the same, just pre-select , quiet, smooth , no problems with vacuum shifting–Toshboy
Well I never had problems with the good old Eaton two speed axles, I was taught how to use them by a lad who worked for Baxters on the Newcastle Quayside in the 50s, The late Jimmy Lawson, When operating the two speed shift you had to keep the throttle down to the floor, Then just lift your foot and bingo it changed into the gear that you had selected, These two speed axles gave a much improved fuel performance when driving a four wheeler Atki/Erf Etc with a four potter Gardner Engine, 4 LK 4 LW Range they used to run on fresh air in those good old days when fuel was very cheap. Regards Larry.
This Dodge tipper that we had Powered by a Perkins N/A Engine had the Eaton two speed axle, Along with a 5 speed ENV Gear box, It performed very well indeed, We had a swop flat body that we used for long haul stuff now and again just to suit customers requirements, It was a cracking motor to drive, It had plenty of power and was very fast if you know what I mean, , With a good payload , Regards Larry.
Lawrence Dunbar:
Well I never had problems with the good old Eaton two speed axles, I was taught how to use them by a lad who worked for Baxters on the Newcastle Quayside in the 50s, The late Jimmy Lawson, When operating the two speed shift you had to keep the throttle down to the floor, Then just lift your foot and bingo it changed into the gear that you had selected, These two speed axles gave a much improved fuel performance when driving a four wheeler Atki/Erf Etc with a four potter Gardner Engine, 4 LK 4 LW Range they used to run on fresh air in those good old days when fuel was very cheap. Regards Larry.
But you couldn’t keep the throttle down to the floor when changing from (for instance) 3rd gear/high axle to 4th gear/low axle or vice versa on a constant mesh gearbox and that was when you heard the ‘rattling’ from the back end until it found its way into mesh. That’s why I was shown to do the axle change after the main gear shift but just before releasing the clutch pedal, and if you timed it right and adjusted the rpm accordingly the axle change was silent. Or you could just turn the radio up, that worked as well!
Lawrence Dunbar:
Well I never had problems with the good old Eaton two speed axles, I was taught how to use them by a lad who worked for Baxters on the Newcastle Quayside in the 50s, The late Jimmy Lawson, When operating the two speed shift you had to keep the throttle down to the floor, Then just lift your foot and bingo it changed into the gear that you had selected, These two speed axles gave a much improved fuel performance when driving a four wheeler Atki/Erf Etc with a four potter Gardner Engine, 4 LK 4 LW Range they used to run on fresh air in those good old days when fuel was very cheap. Regards Larry.
But you couldn’t keep the throttle down to the floor when changing from (for instance) 3rd gear/high axle to 4th gear/low axle or vice versa on a constant mesh gearbox and that was when you heard the ‘rattling’ from the back end until it found its way into mesh. That’s why I was shown to do the axle change after the main gear shift but just before releasing the clutch pedal, and if you timed it right and adjusted the rpm accordingly the axle change was silent. Or you could just turn the radio up, that worked as well!
Pete.
Eaton had a man who went to users of the two speed axle demonstrating how to use it to the best advantage. He went with me for a couple of hours in a Dodge and told me always dip the clutch when changing the axle ratio, which makes sense because it eases the torque input on the diff. He taught me split shifting, for example, on a hill going from 4th gear low axle to 3rd gear high axle. All in all a very worthwhile two hours in his company. And I agree with Bewick, used correctly the two speed axle improved the performance of a lorry.
Lawrence Dunbar:
Well I never had problems with the good old Eaton two speed axles, I was taught how to use them by a lad who worked for Baxters on the Newcastle Quayside in the 50s, The late Jimmy Lawson, When operating the two speed shift you had to keep the throttle down to the floor, Then just lift your foot and bingo it changed into the gear that you had selected, These two speed axles gave a much improved fuel performance when driving a four wheeler Atki/Erf Etc with a four potter Gardner Engine, 4 LK 4 LW Range they used to run on fresh air in those good old days when fuel was very cheap. Regards Larry.
But you couldn’t keep the throttle down to the floor when changing from (for instance) 3rd gear/high axle to 4th gear/low axle or vice versa on a constant mesh gearbox and that was when you heard the ‘rattling’ from the back end until it found its way into mesh. That’s why I was shown to do the axle change after the main gear shift but just before releasing the clutch pedal, and if you timed it right and adjusted the rpm accordingly the axle change was silent. Or you could just turn the radio up, that worked as well!
Pete.
RADIO ■■? , the BMCs I drove were so noisy that you couldn’t even hear the grinding if you mistimed the change , the only radio I ever used was in a Commer ts3 , a huge valve set that took up half the passenger footwell and it only picked up a station when you were stopped .
I know you could change the ratio by slackening your foot off the accelerator but that is a practice I never indulged in as it cant have done the change motor much good IMHO ! But on the subject of how the Eaton two speed improved performance well I suppose I took it to the extreme by converting a single speed Eaton axle to two speed but this Borderer OJM 480L also had the Fuller 610 box which tuned it into an incredible machine ! both in terms of top speed but also for pulling power. You could keep it singing on the M/way grades as you only made a change when the revs dropped by 250 so I’m not kidding when I can say it could ■■■■ all over 8LXB’s and the early F88 and on more than one occasion a driver has come onto the services and then rushed across to look at this Atky and they were mighty surprised to see it was just a ■■■■■■■ 220 engine ! But TBH it was well over geared and not a spec that you would normally order but it was a bit indulgent at the time but it had a very decent Driver at the wheel, as well as cough ! cough ! mesl !
Well IMO If the two speed button was moved up or down when your foot was off the throttle this caused it to go between high & low then go back into whatever gear with a clonk. Not doing any good at all to the diff.Regards Larry.
