Alas, the phenomenon has its own history on a number of threads in this forum. Sometimes its easier to ‘walk round’ it than it is to give it any more energy. Robert
robert1952:
…phenomenon…
Fine choice of word.
[zb]
anorak:robert1952:
…phenomenon…
Thank you, Anorak. It was carefully chosen: diplomacy is riddled with such euphemisms. Robert
No engine is complete without its gearbox. Here are a couple of interesting snippets from CM concerning the DKSE for the UK market. Basically, it tells us that the Continental version used a ZF Ecosplit and the UK version had a 9-speed Fuller, for the reasons given. I’ve often wondered though, if UK-spec DKSEs with LHD still had a Fuller box! Robert
From Commercial Motor article:
September 1979 saw the first major revision to the 2800 range, when DAF announced a super economy version of its 1160 engine, labelled the DKSE. The new power plant was turbocharged and intercooled, as per the original DKS motor, and produced 276hp at a much lower 1,800rpm.
Torque-wise, the DKSE delivered 929lb/ft at 1300rpm and gave a relatively narrow green band width of 350rpm. To cope with this DAF switched to a ZF 16-speed, synchromesh gearbox, which supplied enough ratios to give good driveability. At the time, UK truck drivers enjoyed a higher national speed limit than their European counterparts, so a Fuller nine-speed unit was used for British deliveries. The RTO 9509A’s top cog allowed 66mph at an engine speed of 1800rpm.
From later Commercial Motor article:
March 1982 DAF Fuller 9 speed
Multi-mesh DAF
THE DAF FT 2800 DKSE tractive Fuller RTX 11609A gearbox.
It replaces the current Fuller RTO 9509A on all DKSE vehicles as from March 8, 1982. Both gearboxes are nine-speed constant mesh but the RTX 11609A gearbox was designed for a higher torque capacity: 1,560Nm (1,150Ibft) against 1,288Nm (950Ibft).
DAF says that the increased torque capacity has been achieved by multi-mesh gearing, which means that are always two or more gear teeth in contact at any time. Loads imposed upon the individual gear teeth are thus reduced. The multi-mesh gearing, it is claimed, also provides a smoother torque flow with reduced noise levels.
The gear change pattern on the FT 2800 DKSE is now a normal ‘H’ pattern. The gearbox ratios of the RTX 11609A are said to give similar road performance as the old unit, with an improvement in driveability. There is claimed to be significantly better gearing between the first and second ratios, too.
The RTX 11609A gearbox gives the DAF 2800 DKSE a maximum road speed at governed revs in top gear of 66mph, with a maximum gradient stop and restart of 1 in 3.7.
I looked on the DAF site, and found that its history is very well documented. The P680-based engines are here:
daf.com/en/about-daf/daf-history?page=2
Below is their cutaway drawing of the DKA1160. I daresay those with experience of stripping a P680 can identify some of the improvements. Cav551, are you still here?
robert1952:
No engine is complete without its gearbox. Here are a couple of interesting snippets from CM concerning the DKSE for the UK market. Basically, it tells us that the Continental version used a ZF Ecosplit and the UK version had a 9-speed Fuller, for the reasons given. I’ve often wondered though, if UK-spec DKSEs with LHD still had a Fuller box! RobertFrom Commercial Motor article:
September 1979 saw the first major revision to the 2800 range, when DAF announced a super economy version of its 1160 engine, labelled the DKSE. The new power plant was turbocharged and intercooled, as per the original DKS motor, and produced 276hp at a much lower 1,800rpm.
Torque-wise, the DKSE delivered 929lb/ft at 1300rpm and gave a relatively narrow green band width of 350rpm. To cope with this DAF switched to a ZF 16-speed, synchromesh gearbox, which supplied enough ratios to give good driveability. At the time, UK truck drivers enjoyed a higher national speed limit than their European counterparts, so a Fuller nine-speed unit was used for British deliveries. The RTO 9509A’s top cog allowed 66mph at an engine speed of 1800rpm.From later Commercial Motor article:
March 1982 DAF Fuller 9 speed
Multi-mesh DAF
THE DAF FT 2800 DKSE tractive Fuller RTX 11609A gearbox.
It replaces the current Fuller RTO 9509A on all DKSE vehicles as from March 8, 1982. Both gearboxes are nine-speed constant mesh but the RTX 11609A gearbox was designed for a higher torque capacity: 1,560Nm (1,150Ibft) against 1,288Nm (950Ibft).
DAF says that the increased torque capacity has been achieved by multi-mesh gearing, which means that are always two or more gear teeth in contact at any time. Loads imposed upon the individual gear teeth are thus reduced. The multi-mesh gearing, it is claimed, also provides a smoother torque flow with reduced noise levels.
The gear change pattern on the FT 2800 DKSE is now a normal ‘H’ pattern. The gearbox ratios of the RTX 11609A are said to give similar road performance as the old unit, with an improvement in driveability. There is claimed to be significantly better gearing between the first and second ratios, too.
The RTX 11609A gearbox gives the DAF 2800 DKSE a maximum road speed at governed revs in top gear of 66mph, with a maximum gradient stop and restart of 1 in 3.7.
DAF really lost the plot with that.They already had everything they needed either in the form of the ZF 12 speed constant mesh splitter or the 13 speed fuller.The idea of the 9 speed fuller and even worse synchro eco split were just a retrograde attempt to fix something that wasn’t broke.Luckily I never drove a synchro 2800 only the 12 speed ZF and later the 9 speed fuller in the ATI which you’ve referred to.On that note I’d have put it less diplomatically ‘UK drivers’ ( rightly ) preferred the Fuller to the eco split’.But DAF chose to save a few bob by using the nine speed instead of the 13 speed’ thereby creating a mismatched transmission which contradicted the arguable fuel efficiency advantages of the ATI engine. 
I had a 2800DKSE on a C plate, I don’t know about 276hp, mine had 276spp (Shetland Pony Power)
Carryfast:
robert1952:
No engine is complete without its gearbox. Here are a couple of interesting snippets from CM concerning the DKSE for the UK market. Basically, it tells us that the Continental version used a ZF Ecosplit and the UK version had a 9-speed Fuller, for the reasons given. I’ve often wondered though, if UK-spec DKSEs with LHD still had a Fuller box! RobertFrom Commercial Motor article:
September 1979 saw the first major revision to the 2800 range, when DAF announced a super economy version of its 1160 engine, labelled the DKSE. The new power plant was turbocharged and intercooled, as per the original DKS motor, and produced 276hp at a much lower 1,800rpm.
Torque-wise, the DKSE delivered 929lb/ft at 1300rpm and gave a relatively narrow green band width of 350rpm. To cope with this DAF switched to a ZF 16-speed, synchromesh gearbox, which supplied enough ratios to give good driveability. At the time, UK truck drivers enjoyed a higher national speed limit than their European counterparts, so a Fuller nine-speed unit was used for British deliveries. The RTO 9509A’s top cog allowed 66mph at an engine speed of 1800rpm.From later Commercial Motor article:
March 1982 DAF Fuller 9 speed
Multi-mesh DAF
THE DAF FT 2800 DKSE tractive Fuller RTX 11609A gearbox.
It replaces the current Fuller RTO 9509A on all DKSE vehicles as from March 8, 1982. Both gearboxes are nine-speed constant mesh but the RTX 11609A gearbox was designed for a higher torque capacity: 1,560Nm (1,150Ibft) against 1,288Nm (950Ibft).
DAF says that the increased torque capacity has been achieved by multi-mesh gearing, which means that are always two or more gear teeth in contact at any time. Loads imposed upon the individual gear teeth are thus reduced. The multi-mesh gearing, it is claimed, also provides a smoother torque flow with reduced noise levels.
The gear change pattern on the FT 2800 DKSE is now a normal ‘H’ pattern. The gearbox ratios of the RTX 11609A are said to give similar road performance as the old unit, with an improvement in driveability. There is claimed to be significantly better gearing between the first and second ratios, too.
The RTX 11609A gearbox gives the DAF 2800 DKSE a maximum road speed at governed revs in top gear of 66mph, with a maximum gradient stop and restart of 1 in 3.7.DAF really lost the plot with that.They already had everything they needed either in the form of the ZF 12 speed constant mesh splitter or the 13 speed fuller.The idea of the 9 speed fuller and even worse synchro eco split were just a retrograde attempt to fix something that wasn’t broke.Luckily I never drove a synchro 2800 only the 12 speed ZF and later the 9 speed fuller in the ATI which you’ve referred to.On that note I’d have put it less diplomatically ‘UK drivers’ ( rightly ) preferred the Fuller to the eco split’.But DAF chose to save a few bob by using the nine speed instead of the 13 speed’ thereby creating a mismatched transmission which contradicted the arguable fuel efficiency advantages of the ATI engine.
I drove a 2800 DKSE with a 9-speed Fuller and it was a great wagon to drive. No plot-loss there! Robert
hey Robert, nice to read, in the UK there was a complete other view on gearboxes as here.
But for some customers, stayed to build in Fuller’s till the XF came, not to loose them.
The DKSE was standard Ecosplit, but on special wish, you got a Fuller. It was a good puller for the only 280hp’s
But 90@ 1800rev was the max. Later with the ATI DKXE 90@15/1600rev’s was a disaster and because at that time the norm was already 330hp.
What’s the differents about a RTX, what means the X ■■? was there a lot difference to drive ■■?
Eric,
robert1952:
I drove a 2800 DKSE with a 9-speed Fuller and it was a great wagon to drive. No plot-loss there! Robert
That was only meant in relative terms IE still nice to drive but the 12 speed ZF or 13 speed Fuller were better.In which case the description provided in the article shows the flaw in the idea of using the 9 speed v 12 speed ZF or 13 speed Fuller.IE wider than necessary ratios v a narrow optimum torque band.On that note as I said the move to 9 from 12 or 13 was a retrograde one.
tiptop495:
What’s the differents about a RTX, what means the X ■■? was there a lot difference to drive ■■?Eric,
Personally I preferred the 12 speed ZF splitter in the early 2800 over the 9 speed Fuller in the ATI.
tiptop495:
hey Robert, nice to read, in the UK there was a complete other view on gearboxes as here.
But for some customers, stayed to build in Fuller’s till the XF came, not to loose them.
The DKSE was standard Ecosplit, but on special wish, you got a Fuller. It was a good puller for the only 280hp’s
But 90@ 1800rev was the max. Later with the ATI DKXE 90@15/1600rev’s was a disaster and because at that time the norm was already 330hp.
What’s the differents about a RTX, what means the X ■■? was there a lot difference to drive ■■?Eric,
I think the X = extra teeth. The RTX was a multi-mesh engagement for smoother gear changes. Robert
I`ve had a few 2800 ATIs and they were pretty gutless but nothing compared with the 95 310 ATIs they should have been delivered new with a blindfold
[zb]
anorak:
I looked on the DAF site, and found that its history is very well documented. The P680-based engines are here:
daf.com/en/about-daf/daf-history?page=2
Below is their cutaway drawing of the DKA1160. I daresay those with experience of stripping a P680 can identify some of the improvements. Cav551, are you still here?
It is quite a few years since I worked on a 680, but fewer since I did on a 600 to which I am mentally referring; most recent however being the pre war E102 overhead cam 8.6 below.
The DKA 1160 differs from the Leyland with a Bosch injection pump and a completely different inlet manifold, which as referred to in the text is ‘tuned’ - This would seem to indicate that DAF beat MAN to the game in spite of all the fuss MAN made about their ‘new’ system. The DAF DKA oil filter is mounted in a slightly different place and the engine now has an oil cooler. From memory DAF also fitted an engine breather to the rear o/s block door and did away with the shaft driven alternator arrangement Leyland had used for so long.
tiptop495:
hey Robert, nice to read, in the UK there was a complete other view on gearboxes as here.
But for some customers, stayed to build in Fuller’s till the XF came, not to loose them.
The DKSE was standard Ecosplit, but on special wish, you got a Fuller. It was a good puller for the only 280hp’s
But 90@ 1800rev was the max. Later with the ATI DKXE 90@15/1600rev’s was a disaster and because at that time the norm was already 330hp.
What’s the differents about a RTX, what means the X ■■? was there a lot difference to drive ■■?
Eric,
The was an RTO, an RTOO, an RT and an RTX. The O stands for Overdrive, so the RT was a direct drive 'box. I dunno what the X stands for. I think the extra teeth was an across-the-board update, so it might not be that. There is a thread about Fullers on here somewhere and, IIRC, someone posted a link to a site which explains all the Fuller codes.
The X means overdrive as well I seem to recall. ‘O’ seems more logical,so an improved version maybe?
ramone:
I`ve had a few 2800 ATIs and they were pretty gutless
Compared to the 2500 they were still flying machines.We had one at our depot which was quicker to the point where the fleet engineer took an interest in the tacho traces coming back from it.It turned out that it had been supplied from the factory with a 3300 spec motor by mistake. 
Sorry to mislead you. The RTX did not denote multi-mesh: you could get an RT with multi-mesh (see the 2 scans below). In the meantime I’ve looked up the RTX. Eaton says that O = double overdrive and X = overdrive with direct shift pattern (ie H not U shaped). ‘Overdrive models with X instead of O (like the RTX 11609B) have their full complement of forward and reverse speeds arranged with a direct shift pattern instead of in a standard overdrive pattern.’ Robert
Just out of interest, here is the Multi-mesh red herring:
robert1952:
Sorry to mislead you. The RTX did not denote multi-mesh: you could get an RT with multi-mesh (see the 2 scans below). In the meantime I’ve looked up the RTX. Eaton says that O = double overdrive and X = overdrive with direct shift pattern (ie H not U shaped). ‘Overdrive models with X instead of O (like the RTX 11609B) have their full complement of forward and reverse speeds arranged with a direct shift pattern instead of in a standard overdrive pattern.’ RobertJust out of interest, here is the Multi-mesh red herring:
10
Great bit of detective work the direct drive v over drive shift pattern thing often creates confusion.While in the case of the ATI the range change was also selected by movement of the lever not by a switch.One of the advantages of the ZF 12 speed splitter not only being more gears but also 6 of them being pre selectable splits.
At that time certainly one of the gearbox manufacturers was telling you not to preselect… I thought it was ZF.