Technical data Resources (Engines and gearboxes)

[rookie_one]

Thanks for the info

And weirldy enough(or perhaps not), BOTH Euro5 and EEV engines use the same curve

[xXCARL1992Xx]

because it is the same engine but with better cleaning, EEV is still Euro 5 but just shows the truck is even more environmental friendly then needed for Euro 5, in the source he showed the engines are called Euro 5 EEV, E5 standard engines with better exhaust cleaning

[TurboJ]

The curves IRL would likely not be identical if the only change was the exhaust system - more complex after treatment system does usually increase flow resistance in the exhaust. However, as there is always some headroom in the power and torque output with factory programming, it is also likely that they could replicate the performance exactly, by simply adjusting the fuel and boost settings on the engine management. But as we don't have access to detailed information like that, I can only guess. At any rate, if the curves are truly an exact match, it should usually be possible if the changed exhaust system was accompanied by a suitable new programming of the engine controls. If the manufacturer did not do this, then having a different exhaust system would have some effect on the net power.

OTOH, the advertised curves themselves are not exact, so the possible changes to net output may well be within margin of error.

Then when manufacturers moved onto Euro 6 specification the new emission standard was so much tougher than before that most manufacturers needed to redesign many fundamental aspects of the engine package. In many cases this is when manufacturers switched from unit injectors to a common rail system, and also often from fixed geometry turbocharging to electronically controlled VGT. The bottom line with Euro 6 is that they needed to do a lot more than just change the after treatment system as was the case with EEV. Interestingly, to match (or usually improve) the overall performance of the older generation engines, manufacturers actually increased engine performance more than you can see on the paper data - a big portion of this increase is swallowed by the emission control systems, so in order to have same or better net performance on an Euro 6 engine, the gross power needs to be noticeably higher.

The fact that the latest generation engines are usually the most powerful versions of each respective engine just goes to show how far engine technology has come in the last 10-15 years. Despite being pushed ever harder with stricter emission limits, total power output still manages to grow.

[rookie_one]

Depend on the manufacturers.

Volvo is actually well known for managing to keep the exact same curve on the many revision of the Euro6 engines (all the way from euro6a to euro6c, some of them changed slightly with euro6d-temp and 6d), although it could be attributed to them simply rebrandings their engines, as they do seems to be a bit in front of the curve on emissions. Hell, the Euro5 and EEV version of the D16G750 have a very similar torque curve to the D16k750 Euro6a to 6c.

Also, small update :
MAN FINALLY got their damn Euro6d spec sheets out.

[rookie_one]

Asking for help from everyone :

I'm having lots of difficulties getting info on the DT12 transmission, especially the ratios.

If someone can get them for me, I would be very grateful!

Here the full list of what i'm looking for :
[ external image ]

Thanks

[rookie_one]

Well, still looking to find the HE, V and VX (equivalent to DC, OC and OD variants in the picture above), but at least I found the rest (equivalent to DB, OB (both equivalent to HL in the new family), DA and OA(both equivalent to the H in the new family) variants which are what will be mostly sold), I actually just had to stop looking in Detroit Diesel documentation and look into the JOBBERS documentation, which tell which one is equivalent to which Mercedes Benz transmission

According to this :
https://www.ultpowertrain.com/Content/I ... TB0620.pdf

DT12-DB and DT12-DHL equivalent to MB G211-12
DT12-OB and DT12-OHL equivalent to MB G230-12
DT12-DA and DT12-DH equivalent to MB G281-12
DT12-OA and DT12-OH equivalent to MB G330-12

And it's added to my archives!

[Snoman]

I was never able to find one single source for any detailed detroit info, but I basically came to the same conclusion as you did based on reported gear ratios and or torque ratings from many different publications. And yes finding service, repair or PTO manuals often give you the most info when the manufacturer refuses to give up the info in their press releases.

These are all the gearbox models I found from a 2018 Cascadia publication, obviously they are just separated by their max torque limits, but I could not find out why the 2 DB models had the M designation. So far only the Western Star is reported to have the newer vocational spec gearboxes available.

DT12-DA-1550
DT12-DA-1650
DT12-DA-1750

DT12-DB-1250
DT12-DB-1350
DT12-DB-1450M
DT12-DB-1550M

DT12-OA-1550
DT12-OA-1650
DT12-OA-1750
DT12-OA-1850
DT12-OA-2050

DT12-OB-1250
DT12-OB-1350
DT12-OB-1450
DT12-OB-1550
DT12-OB-1650

[rookie_one]

@Snoman a document I found and added finally told me which gearbox was what, at least for the OA and DA(also known as the H series) and the DB and OB(which are the HL series), basically these 4 are rebranded Mercedes gearboxes (I was able because the document in question came from a jobber and basically showed which transmission is equivalent to what)

For the torque ratings, I don'T have much info but I think those are related to the clutch and not the internals of the gearbox, it would not make sense for every DT12-OA/OH having the same internal as the G330 but lower torque ratings, unless the difference between each of the transmissions is the clutch.

Here for the equivalency, what I found :
[ external image ]

DB/DHL = G211
OB/OHL = G230
DA/DH = G281
OA/OH = G330

For the HE, V and VX, the V and VX were added to the 49X in-game by SCS in the latest beta, so we got the ratios now.

And the Transmission limit document from Detroit that I found showed this :

[ external image ]

We can see there that the HE and V are basically the same exact gearboxes, (even got the same internal Detroit Diesel name, DC1 and OC1), so the differences are probably only the programmation.

[rookie_one]

Small update : added a few EPA2010 brochure, including the EPA2010 PACCAR MX brochure

[galimim]

@rookie_one any chance of getting your hands on the new International A26 rating? IIRC you got your hands on some detailed torque and power curves