Out of Sydney the load for an NR is 9-1300 tonnes depending on the ruling grades and much of the time 93s are used as an NR substitute .
Drivers that have had TTs 92s CEYs in coal service say they do very well and in some cases they claim the GEs do better than the GT46ACes . We don't have and probably never will have the EDIs and a TT at SFT is a rare bird and a hauled dead one .
Anyway everyone has their favourites with EMDs and GEs , like Holden's and Fords , and these are some of the claims that others who have driven them claim to be the case .
Firstly is that when starting Hunter style coal trains on grades the GEs do it a bit easier than the EDIs though the earthquake thing is real enough .
Secondly the EDIs are supposed to have a huge appetite for fuel compared to the GEs .
Third claim is that the 710 in GT46ACEs sits quite low in the frame so they get the shallow lower volume sump , these prime movers are said to be going through a lot of lubricating oil and that's a pain when there isn't a lot of sump capacity .
Now to load testing . Most interested here read about the Cowan Bank trials with 92s and SCTs , three of each with 4500 trailing tonnes and water sprays to simulate wet conditions . The result was that both types lifted the load easily enough but the SCTs were faster and this better suited the then Rail Corps time tabling requirements .
Since then later build C44ACi units with different inverters computers etc like CF44s CEYs 93s etc are out and about and no one seems to complain about how they perform .
The CEYs were said to be load tested up Zig Zag with up to 5300 trailing tonnes and could have done better to prove the point but I think the ask was 46-4800T for three units in normal service .
From time to time you hear rumours that an engine spits the dummy on a long twisty grade and the crew struggles on whilst ever the horse on its knees keeps the scenery moving . Hard to imagine two diesels getting the best part of 5000 up the river bank but vine seems to think it's a reality .
I have had zip to do with the EDIs other than crawling all over the one that was in our terminal after a rebuild to straighten things out . My observation is that yes the prime mover is low in the frame and that the screens / dash look a bit agricultural . The bogies are involved looking things and being semi steering , which some claim is BS , should in theory work better than the roller blades under the C44ACis .
I didn't look very closely at the traction motors on that TT and again if they are higher capacity ones than GEs they should work better overall .
So the question is how does more horsepower semi steering bogies and larger traction motors struggle to be line ball let alone better than at least the later C44ACIs ? I suppose if the tank is full the C44 is heavier so has a bit more weight on its driving wheels but better performance surely can't be put down to the hot plate - in a 93 anyway ....
Seriously though the later built units with different computers inverters software and a lil more horsepower may be enough of a difference over a 92 to tip the odds in their favour .
It would be interesting to rerun the Cowan Bank trial to see if more current technology shows the General how its done . The thing is that CEYS are doing it regularly anyway on the North and West and Illawarra and word is CEYs and 93s cope real well on Illawarra mountain as well .
A number of grey GT46ACEs are still sitting at Cardiff and they are said to be it for Australian built EMD based units , UGL is still churning out C44ACis and probably will while ever they can keep a sustainable production line going and make reasonable money out of it .
If / when PN Northern Coal needs more engines it will be interesting to see what they buy though you'd think the answer would be C44 ACHis since they blitz anything else made here .