Volvo B10M Mk IV DM's with 4-speed Voith transmissions

SBS2601D SG

We've known for some time that the existence of this peculiar gearbox on some of the early MKIV DMs. But this peculiarity must be the least covered for some reason. For the uninitiated, the 2nd overdrive kicks in only close to 60km/h and is therefore hard to identify under usual road conditions.

My other guess is that not all of the Voith MKIV DMs are of the 4 speed variant. The problem now is: which are the ones?

Everyone knows the ZF MKIIIs, but few can identify completely this interesting sub-variant.

Here's those I can confirm:

884S, 888G, 893R, 894M, 903X.

Anyone else know of any others?

It would be a pity if we do not share this rather interesting piece of information before their impending retirement.

^tamago^ SG

886L.

SBS2601D SG

A lot of the information floating around the internet regarding this chassis is not accurate as well.

Some of them do not use the THD102KF as believed. The performance difference and curve resembles more of the THD101GC....the same engine that powers the MKIIIs.

In short, you could technically have many combinations depending on which engine is mated to which gearbox.

An example would be that 893R and 894M are likely to have the THD102GD coupled to the Voith 4-speed. 908R, the THD102GC with the ZF4, and 909E, the THD101GD with the ZF4, 905R, the THD101GD with the Voith 3 speed.

Very confusing indeed.

AEW5001 SG

883, 888, 905.

Scania SG

15 of them. 883U-889D, 891X-894M and 903X-906M.

SBS 1000U SG

My other guess is that not all of the Voith MKIV DMs are of the 4 speed variant. The problem now is: which are the ones?

Everyone knows the ZF MKIIIs, but few can identify completely this interesting sub-variant.

Here's those I can confirm:

884S, 888G, 893R, 894M, 903X.

Anyone else know of any others?

It would be a pity if we do not share this rather interesting piece of information before their impending retirement.

Actually it is the best that someone can make a list of which Volvo B10M MK4 DMs uses.

- ZF

- Voith

- THD102GC

- THD101GD

THis model is rather interesting. Lots of combinations.

TIB1051D SG

Actually it is the best that someone can make a list of which Volvo B10M MK4 DMs uses.

- ZF

- Voith

- THD102GC

- THD101GD

THis model is rather interesting. Lots of combinations.

THD102KF, instead of THD102GC.

TIB1051D SG

Actually i dun rly mind checking them out. Just that i might take some time.

SBS2601D SG

15 of them. 883U-889D, 891X-894M and 903X-906M.

Do all 15 have the 2nd overdrive?

tib1051d> that would be most appreciated if you could help shade some light on this.

Scania SG

Do all 15 have the 2nd overdrive?

tib1051d> that would be most appreciated if you could help shade some light on this.

Unsure of that, but I think they should have the same specifications...its already such a small subfleet.

SBS2601D SG

It has come to my attention that these 15 MKIVs are not fitted with the THD101GC as earlier believed, but the THD101GD rather. This engine has a higher power rating.

I had heard talk that its 285bhp, which puts it in the class of the DH10A powered MKIV....which would appear to be the case indeed when one compares the performance of both MKIVs.

Yet another source, this time from Mike Davis, states that this particular engine develops 270++bhp (cant remember the exact figure)....but then he went on to state all 115 were fitted with the ZF4 which was clearly wrong. This figure also seems believable because the THD MKIV has a little more difficulty climbing slopes than the DH10A MKIV.

Obviously my backside is no accurate instrument and therefore I seek some light on this.

Scania SG

It has come to my attention that these 15 MKIVs are not fitted with the THD101GC as earlier believed, but the THD101GD rather. This engine has a higher power rating.

I had heard talk that its 285bhp, which puts it in the class of the DH10A powered MKIV....which would appear to be the case indeed when one compares the performance of both MKIVs.

Obviously my backside is no accurate instrument and therefore I seek some light on this.

And for the breakdown for the B10M fleet with respective power ratings for each engine:

Volvo B10M Mk I (THD100EC (245 hp)/??) - SBS9C (1) - Vanhool
Volvo B10M Mk II (THD101GC (242 hp)/ZF4HP500)- SBS1696L-SBS1895D (200) - WA 'PS' and DM
Volvo B10M Mk II (THD101GC (242 hp)/Voith 381.4)- SBS582M-SBS875T, SBS878K-SBS881A (298) - DM
Volvo B10M Mk II (THD101GC (242 hp)/ZF4HP500)- SBS876K and SBS877M (2) - DM
Volvo B10M Mk IV (THD102KF (245 hp)/Voith) - SH951M-SH970H, SBS2689B-SBS2838M (180) - Soon Chow and DM3500
Volvo B10M Mk IV (THD101GD (273 hp)/Voith)- SBS883U-SBS889D, SBS891X-SBS894M, SBS903X-SBS906M (15) - DM
Volvo B10M Mk IV (THD102KF (245 hp)/ZF4HP500) - SBS882Y, SBS890Z, SBS895K-SBS902Z, SBS907K-SBS996C, SBS1896B - SBS1999M, SBS2593T-SBS2688D (300) - DM & WA 'Strider'

All the above are -60/-61 buses with 12m/40 ft approx length

Unsure of whether the following two have uprated engines or not:
Volvo B10M-70 Mk IV (14.5m) (THD102KF/ZF4HP590) - SBS997A (1) - DM
Volvo B10MA-60 Mk IV (19m) (THD102KF/ZF4HP590) - SBS998Y (1) - DM

Taking a VIN as an example,

YV31MGC11JA018185 (SBS1840L if anyone is wondering)

The 6th and 7th digits of the VINs of Volvo B10Ms denote the engine type, of which the Volvo B10M Mk2s and 3s have GC; Mk4 DM with Voiths have GD; all other Mk 4s have 2F.

Which I believe EC denotes THD100EC, GC denotes THD101GC, GD denotes THD101GD, 2F denotes THD102KF.

I do believe that the choice of gearbox and the tuning of gearbox does affect the performance of the buses. Also, the same engine model may had slight tweaks over the years, which may account for certain differences. And lastly, every vehicle is different, even if they look the same, and have the same specs, they will still perform differently. So that may explain differences in apparent power throughout the fleet.

All in all, SBS (including SBSL) operated a total of 988 Volvo B10Ms with 7 different engine/transmission combinations and 12 distinct types of buses within the family.

Above information is to the best of my knowledge, do feel free to correct or add on.

SBS2601D SG

DM3500 would apparently be using the DH10A engine. The same that powers the B10TL and supposedly, the Batch III VO3X. 285bhp. Performance characteristics supports this...this B10M is easily the fastest amongst all other types.

billlmf SG

Basically those DM3500s are using THD102KF engine according from One Motoring, you may noticed that the chassis number was displayed YV31M2F15VA046544 (SBS2689B), with D10A engine should be 4A~~

Scania SG

Basically those DM3500s are using THD102KF engine according from One Motoring, you may noticed that the chassis number was displayed YV31M2F15VA046544 (SBS2689B), with D10A engine should be 4A~~

For the DH10A245 (ie those used on B10Bs/B10BLEs/B10Ls and select B10Ms elsewhere), they have A5 in their engine position.

Say a Volvo Bus VIN (excluding Olympians):

YV3(&&)((%%).................

The && represents the chassis model and the %% represents the engine model

For B10Ms, the chassis code will be 1M, for B10Bs R1, B10BLEs R4 and B10Ls R5.

For the engine code, besides those mentioned above, DH10A285 would have A6, and THD102KB (285 hp) would have 2B.

And my apologies as SBS998Y is using a THD102KB instead of a THD102KF as stated above as its VIN is YV31M2B15TA044974.

Here are a few examples:

B10M Mk 3: PZ1312S Big S’Holiday YV31MGD14PA031746 (THD101GD)
B10M Mk 4: PA964Z Woodlands Transport YV31M2B14TA045517 (THD102KB)
B10M Mk 4: PA3267H Westpoint Transit YV31MA6171A053774 (DH10A285)
B10B: 3559 (m/o 012) STA NSW YV3R12F16TA002416 (THD102KF)
B10B: m/o 8597 ComfortDelgro Cabcharge YV3R1GC15PA000194 (THD101GC)
B10B: 4371 MO ComfortDelgro Cabcharge YV3R1A5111A007953 (DH10A245)
B10BLE:SBS1688K SBS Transit YV3R4A512VA003102 (DH10A245)
B10BLE: This Example YV3R4A616Y1006751 (DH10A285)
B10L: 582 (582JVZ) Brisbane Transport YV3R5A518VA001030 (DH10A245)

Sources: Bus Australia Fleetlists, Brisbane Transport (enthusiast) fleetlist and own records.

The B10TLs use the D10A engine instead of DH10A.

Possible reasons why the Mk 4s/DM3500 feel powerful would probably be the newer model of Voith gearboxes and/or the different tuning of gearboxes. Also note that even though the THD101GD is rated at 273 hp, it produces 1040 Nm of torque @ 1400 rpm, while the THD102KF, rated at 245 hp, produces 1050 Nm @1250 rpm, but I am unsure whether the THD102KF would produce a substantial increase in performance (in terms of accleration) over the THD101GC.

TIB1051D SG

Alright. As i promised earlier, I tried doing up some confirmation of the buses. Only confirmed for SBS882Y to SBS910A. includes VIN and engine used currently.

0882Y - YV31M2F13SA043153 - THD102KF
0883U - YV31MGD16SA042482 - THD101GD
0884S - YV31MGD16SA042286 - THD102KF
0885P - YV31MGD10SA042476 - THD101GD
0886L - YV31MGD1XSA042288 - THD102KF
0887J - YV31MGD14SA042478 - THD101GD
0888G - YV31MGD18SA042290 - THD101GD
0889D - YV31MGD16SA042479 - THD101GD
0890Z - YV31M2F16SA043342 - THD102KF
0891X - YV31MGD14SA042481 - THD102KF
0892T - YV31MGD19SA042475 - THD102KF
0893R - YV31MGD11SA042289 - THD102KF
0894M - YV31MGD12SA042477 - THD101GD
0895K - YV31M2F17SA043401 - THD102KF
0896H - YV31M2F11SA043345 - THD102KF
0897E - YV31M2F11SA043166 - THD102KF
0898C - YV31M2F17SA043155 - THD102KF
0899A - YV31M2F19SA043156 - THD102KF
0900D - YV31M2F12SA043158 - THD102KF
0901B - Deregistered
0902Z - YV31M2F10SA043160 - THD102KF
0903X - YV31MGD12SA042480 - THD101GD
0904T - YV31MGD18SA042483 - THD101GD
0905R - YV31MGD18SA042287 - THD102KF
0906M - YV31MGD1XSA042484 - THD102KF
0907K - YV31M2F13SA043346 - THD102KF
0908H - YV31M2F15SA043154 - THD102KF
0909E - YV31M2F14SA043579 - THD102KF
0910A - YV31M2F10SA043580 - THD102KF

if you have noticed, those MKIV DM fitted with Voith gearbox originally come with a THD101GD engine, but some have been changed to a THD102KF unit.

TIB1051D SG

and basically to clear up some doubts.

B10M DM3500s are using THD102KF engine.
all our VOs (no matter 2-axle or 3-axle, Batch I, II or III) are using TD102KF engine.

as for B10BLE,
demo (1688K) - DH10A245
CNG - GH10B245

B9TL...
CDGE - D9A300
Wright - D9B310

SBS2601D SG

Very interesting read.

Another query is why the WA MKIVs appear better in performance than the DM MKIVs?

They should be using the same powertrain. Is the WA body lighter than the DM one?

SBS2601D SG

Slightly off-topic also, I was a surprised to conclude that the MKIV DM3500 was more than a match for the SMRT 0405s.

Side by side, with my lightly loaded 854 BC bashing the pedal, the packed and crowded DM3500 on 5 still could maintain abreast with my bus.

My bus was no slow-poke in case you wonder. The crazy Indian BC took only 20 min from Bedok Int to Hougang Sports Complex at around 10+PM when it should usually take 35 min. Bamboozling rocket speed all the way.

nfshp253 SG

The strange thing about the B10Ms are their seemingly slow speed at all times although they might going at 60 or accelerating hard.