[coriollis]

Originally Posted by Mpower

Do you have any more details on the FE & reliability issues of the
was the Sharma accident due to product failure?

AFAIK, the FE was abysmal. I remember coming from Hyderabad to Pune in Sri Kalleshwari travels, the bus was just flying. But when asked about the FE, the answer was 1.5 kmpl (single axle). Volvo generally returns 2.3 to 2.4 in case of pedal to metal style driving.

I travel at least for 10 days a month, I have yet to meet a driver who is satisfied by the Merc product.
Disadvantages listed are:
1. Brake problem.
2. AC failure.
3. Very high NVH.
4. Very costly spares.

One of the driver in VRL, who was with prasanna travels earlier said that drivers refuse to drive Merc due to their lack of confidence in braking. He left the job as he was put on the Nagpur route on which they ply their pair of Mercs.

Sharma accident was on Bangalore Mumbai route. AFAIK it hit some vehicle from behind damaging the entire frontal facia. This is clearly due to lack in good braking power.

Cheers,
Abhijeet

[Dodge_Viper]

Don't they have strict standards regarding crucial components like brakes? Now poor brakes on such a huge vehicle, whether it's a bus or truck is a sure recipe for disaster.

[Ashley2]

Originally Posted by Mpower

Do you have any more details on the FE & reliability issues of the engines?
What is lacking in the cooling system and was the Sharma accident due to product failure?

Originally Posted by coriollis

AFAIK, the FE was abysmal. I remember coming from Hyderabad to Pune in Sri Kalleshwari travels, the bus was just flying. But when asked about the FE, the answer was 1.5 kmpl (single axle). Volvo generally returns 2.3 to 2.4 in case of pedal to metal style driving. ..

By any chance Mercedes was better than Volvo in terms of fuel performance and parts pricing. Infact this was the selling point of Merc over Volvo in many STU's and private operators. Big shots like KPN, Neeta were importing parts of Volvo directly from middle east to save part price. But in case of Mercedes the landed OE price was itself cheaper by almost 30%.
What went completely wrong was the reliability factor. When reliability becomes question mark, people will lose confidence in the product - that too in the level of 1 cr product.

With all this there is no single Mercedes Benz running in Mumbai - Bangalore route, and its all either Volvo or Ashok Leyland ( Taken for granted that this route is the testimony)

Wrt cooling system, Volvo has a PTO driven (hydraulic) system where in Merc has a regular RFD (belt driven). Though performance wise there is no issue, the Volvo's type is more sophisticated and trouble / maintenance free. So when Merc was with old school type, that didn't fetch the premium as the Volvo.

Sharma's accident does'nt mean that braking is an issue in Merc but it was perceived in that manner.
One information was in earlier coaches, there was higher brake lining wear (this doesn't mean reduced braking) as the retarder was not foot pedal integrated. This was later retro fitted by Merc.

[Tejas Ingle]

Originally Posted by Ashley2

By any chance Mercedes was better than Volvo in terms of fuel performance and parts pricing. Infact this was the selling point of Merc over Volvo in many STU's and private operators. Big shots like KPN, Neeta were importing parts of Volvo directly from middle east to save part price. But in case of Mercedes the landed OE price was itself cheaper by almost 30%.

Mercedes actually is also less prone to being off road due to technical issues, but once off road, the spares aren't available quickly. The bus also is more stable on road due to broader suspension setup, it has no cooling problems in ghats and has a better pick-up. The body is stronger and hence safer.
One interesting fact that I came accross was that few operators allow inexperienced drivers on Mercs because of the robustness of the vehicle. At the same time, the bus is not plying on long routes because of spares issue.
There are better chances of improvement though since Daimler India Commercial Vehicles (DICV) is handling the product now. DICV is commercial vehicle oriented and is taking better care.

[audioholic]

I cant find the post but someone mentioned that Mercs come with drum brakes. Is it really true?
And arent volvos equipped with ABS too?

Originally Posted by Tejas Ingle

The body is stronger and hence safer.
One interesting fact that I came accross was that few operators allow inexperienced drivers on Mercs because of the robustness of the vehicle. At the same time, the bus is not plying on long routes because of spares issue.

Could you elaborate how the body is stronger and safer? Pardon me, as I have no idea about bus construction. Hence I would like to know more.

However, I do not agree with the point that inexperienced drivers must be allowed just because the vehicle is robust or so. Moreover, drivers must be trained to handle the extra power and controls rather than anything to do with robustness. With the power that a merc or a volvo offers compared to a conventional bus, and the various equipment like retarder, etc that is offered in addition, drivers must be trained to use them. That is what Volvo does in training new drivers. I dont understand how a robust bus can mean that a non experienced driver can drive the bus.

[Tejas Ingle]

^^Yes, Mercs have all drums.

[Ashley2]

Originally Posted by Tejas Ingle

....The bus also is more stable on road due to broader suspension setup, ..... The body is stronger and hence safer.

You are right about the suspension setup.
Mercedes has a stable suspension than Volvo and so is the reduced body roll. This is also complemented by the fact, Mercedes ULW also higher.
Apart from this Mercedes Benz has higher luggage space, higher ground clearance (wrt retarder position), Increased engine oil change frequency, better dummy axle tyre life etc.

Also engine was more efficient and SFC was superior considering the fact 12L, 360hp Vs 9L 340hp of Volvo.

There were no body related issues like windscreen crack.

Originally Posted by Tejas Ingle

....There are better chances of improvement though since Daimler India Commercial Vehicles (DICV) is handling the product now. DICV is commercial vehicle oriented and is taking better care.

To settle down all the issues, Mercedes was to launch a new product in 2012 itself. But that has not taken place due to organisation restructure.
May be with new team on board, fresh service and products can be expected.

[Tejas Ingle]

Originally Posted by Ashley2

Increased engine oil change frequency,

Also engine was more efficient and SFC was superior considering the fact 12L, 360hp Vs 9L 340hp of Volvo.

There were no body related issues like windscreen crack.

To settle down all the issues, Mercedes was to launch a new product in 2012 itself. But that has not taken place due to organisation restructure.
May be with new team on board, fresh service and products can be expected.

I guess you mean decreased oil change frequency. It is 35k for Merc which I believe is more than Volvo.
So that makes the bus much more cheeper to maintain. Even most of the spares are cheaper than Volvo. Also the breakdown frequency is less. Consumables cost much lesser like brake liners as you have pointed out. They too wear after a whoping 4Lakh kms + in some cases where trained drivers were using the brakes in unision with the retarder. The low tech pulled down the maintainance cost further without compromising the usability and comfort. For instance, it has a simple belt driven viscous fan as opposed to a hydraulically driven longitudinally mounted fan on its counterpart (you have mentioned it in an earlier post). How does it affect the occupants or the engine performance as long as it is keeping the engine at an optimum temperature? In fact, it does a better job than the one on Volvo as it is laterally mounted and draws in more air as the bus speeds up. Many Volvos are facing overheating problems.
All these points make this an excellent profit earning commercial vehicle.
Of course it has been plagued by a problems like a few engine failures. But this can be backed up by a strong after-sales support where Volvo is way ahead at present and this field is seeing improvements in Merc too.

Originally Posted by audioholic

I cant find the post but someone mentioned that Mercs come with drum brakes. Is it really true?
And arent volvos equipped with ABS too?

Could you elaborate how the body is stronger and safer?

However, I do not agree with the point that inexperienced drivers must be allowed just because the vehicle is robust or so. Moreover, drivers must be trained to handle the extra power and controls rather than anything to do with robustness.

In case of an accident, a Merc body holds up much better than that of a Volvo's. The extent of damage is much lesser. Thus it saves more lives. Now many people here would argue that it cannot be concluded that which vehicle holds better as that depends on a severity of impact. I agree. But I am saying this based on comparisons of several crashes of Mercs and Volvo's. Even several drivers I have spoken to vouch for the safety provided by Merc. Most of them told me that the chances of survival for the driver and cleaner are much better in Merc than a Volvo in case of a head-on. Even the driver seating height is a bit more in Merc which makes him feel safer.

Inexperienced drivers shouldn't even come close to these buses as they are powerful, and there are about 45 lives in the hands of the driver. However, the problem is that a driver drives a different vehicle on every trip. So the trained drivers for Mercs shift to some other bus and untrained ones take their place as they are available at the time of trip. Even if a particular bus is appointed to a particular driver, the switch happens when the driver goes for a leave once in a while.
So the inexperienced new drivers who keep coming to an operator are given the Mercs, as it is more forgiving. A Volvo will throw tantrums if not driven like it should be. In all the cases where the trained drivers are strictly driving the Merc, the operator is geting great results.

Volvo too has ABS. Merc employs ABS on drum brakes.
Coming to the brakes, it will not be completely right to say that Merc has bad brakes. This is comparative. Since the driver keeps switching between Merc and Volvo, he finds the Volvo brakes better. He uses them without the retarder and the bus stops just fine. The brake pad change frequency is very high in Volvo due to this. When the same driver drives a Merc, he tries to drive it like a Volvo, without using retarder and cannot stop the bus. Even if the retarder is integrated with the foot pedal, it takes some time. This leads to heating of the liners which further deteriorates the braking.
The trained drivers who drive only Mercs are not complaining about brakes. They drive with some foresight and can handle the bus even in cases of emergency braking. Because the liners operate at a lower temperature.

[coriollis]

Originally Posted by Tejas Ingle

In case of an accident, a Merc body holds up much better than that of a Volvo's.

Is it due to the square-tube space frame structure of the body cage that is bent in U shape and not welded ?

[Tejas Ingle]

Originally Posted by coriollis

Is it due to the square-tube space frame structure of the body cage that is bent in U shape and not welded ?

Yes it is, and not only that, there is overall more of frame in the Merc. I mean more square tubes that support the structure which makes it very strong. Volvo on the other hand has a huge void below the drivers deck where the spare wheel is supposed to be suspended. Only two longitudinal square tubes on either side of the spare wheel. Also the overall material used is relatively less.

[Ashley2]

Originally Posted by Tejas Ingle

I guess you mean decreased oil change frequency. It is 35k for Merc which I believe is more than Volvo.

Thanks for correcting
Yes, Merc is at 35k and Volvo is at 25k.

Originally Posted by Tejas Ingle

... How does it affect the occupants or the engine performance as long as it is keeping the engine at an optimum temperature?

I never commented about the performance, but only on the technology front.

Originally Posted by Tejas Ingle

In fact, it does a better job than the one on Volvo as it is laterally mounted and draws in more air as the bus speeds up. Many Volvos are facing overheating problems.

Volvo never had cooling problems. If at all there was any, routes like Blore- Jodhpur would not have come into existence.

Originally Posted by Tejas Ingle

So the inexperienced new drivers who keep coming to an operator are given the Mercs, as it is more forgiving. A Volvo will throw tantrums if not driven like it should be. In all the cases where the trained drivers are strictly driving the Merc, the operator is geting great results.

None of the operators have 100% trained drivers to drive these buses. Absolutely they require training to get familiar with the features. It’s not practical to send all the drivers for training also.
Thoughts like untrained drivers should not come close, are all our personal views as after all every driver will take care of their safety first. You can never push a driver beyond his limits, no matter what ever sophistication you have in your bus nor the training you give.

Originally Posted by Tejas Ingle

…. Since the driver keeps switching between Merc and Volvo, he finds the Volvo brakes better. He uses them without the retarder and the bus stops just fine. The brake pad change frequency is very high in Volvo due to this. When the same driver drives a Merc, he tries to drive it like a Volvo, without using retarder and cannot stop the bus. Even if the retarder is integrated with the foot pedal, it takes some time. This leads to heating of the liners which further deteriorates the braking.

The trained drivers who drive only Mercs are not complaining about brakes. They drive with some foresight and can handle the bus even in cases of emergency braking. Because the liners operate at a lower temperature.

First of all, you cannot apply brakes without retarder. At any point when brakes are applied (brake pedal is pressed), retarder gets actuated and only after subsequent braking, service brakes come into picture. Retarder gives initial deceleration and service brakes are used for stopping. It was in earlier days, when these two were separated and now they are all integrated into brake pedal.
ABS is integrated into retarder, service brakes, engine brakes and EBS is the single control module which takes care of all this.
At any point disc brakes are effective over drum brakes and that was the problem Mercedes was having.
Apart from this other features like retarder cruise control is available in both Merc and Volvo.

[Tejas Ingle]

Originally Posted by Ashley2

Thanks for correcting
Volvo never had cooling problems. If at all there was any, routes like Blore- Jodhpur would not have come into existence.

I have come across cases of overheating in the same area (Jaipur, Jodhpur etc) especially in summers with full load of passengers and A/C. Otherwise there is no problem with cooling.

Originally Posted by Ashley2

None of the operators have 100% trained drivers to drive these buses. Absolutely they require training to get familiar with the features. It’s not practical to send all the drivers for training also.
Thoughts like untrained drivers should not come close, are all our personal views as after all every driver will take care of their safety first. You can never push a driver beyond his limits, no matter what ever sophistication you have in your bus nor the training you give.

I completely agree with you, but what I want to say is that the operator can atleast manage such that the buses will be interchanged amongst the trained drivers. Even if an untrained driver is needed to drive, the second driver can be a trained one (for long routes). I dont know much about Volvo, but Merc trains 2-3 drivers per bus sold. So I think it is sufficient and operators should manage them smartly. My concern is that there is no thought given at all towards the training of the drivers. There are cases where a cleaner learnt to drive from his 'Ustaad', got his license, and started driving one of these buses. The driver training course- 3days including theory and practical- not only makes the drivers familiar with the systems but also covers topics like safety, night driving, efficient driving, importance of foresight etc.
Its not about pushing the driver to the limit, its about preventing the driver from pushing to his limits.

Originally Posted by Ashley2

First of all, you cannot apply brakes without retarder.
ABS is integrated into retarder, service brakes, engine brakes and EBS is the single control module which takes care of all this.
Apart from this other features like retarder cruise control is available in both Merc and Volvo.

Yes, you cannot apply brakes without a retarder, unless the foot pedal switch is turned off. But retarder takes a bit longer to actuate than the service brakes. Service brakes operate instantaneously. This too is covered in the driver training. Drivers are told how to use only retarder effectively. This is followed by the drivers of several operators in the south. They use the service brakes only after the speed comes below 40kmph (Except in emergency or sudden braking). Mostly they use the retarder stick to control the bus. Untrained drivers tend to go very close to the vehicle in front of them and brake at the last moment. So the max work is done by the service brakes. That is what I wanted to say.
ABS and Retarder control units are separate in the Merc. Retarder has nothing to do with other braking systems. Engine brake is controlled by the Engine control unit. Exhaust brake is also controlled by the ECU. EBS is not there in Merc. Also cruise control is not present on the Merc 2-Axle, its there on the 3-Axle.

[Mpower]

Originally Posted by Ashley2

Volvo never had cooling problems. If at all there was any, routes like Blore- Jodhpur would not have come into existence.

What is it thats demanding about BLR Jothpur route? AFAIK, Cooling deficiency is more evident in hot weather mountain routes that involve climbing (maybe Thirupathi?)

[coriollis]

Originally Posted by Mpower

What is it thats demanding about BLR Jothpur route? AFAIK, Cooling deficiency is more evident in hot weather mountain routes that involve climbing (maybe Thirupathi?)

BLR Jodhpur route is close to 2k kms. So the engine running is close to 36-38 hrs without a prolonged break. That its demanding IMHO.

Cheers,
Abhijeet.

[TheARUN]

There are always exceptions to the rule, you will always have some Mercs that run flawlessly and you will always have some Volvos give endless problems, what I concede to Volvo is that they took the first mover advantage and have been able to plan better, they were able to beat the Merc in the market, how good each bus is intrinsically we might never know, but the Volvo is bus lengths ahead of the Volvo at the moment

Also, what about Owner training? I think they can have a more comprehensive training program for the Owner and then let the Owner top up on the training programs they give to their Drivers inturn. A trained Owner will be worth more than a bunch of trained Drivers unless Drivers manage the Bus as a whole end-to-end