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The clutch disc, cover is the same for these AMT vehicles. For K10, the clutch control is done by modulating the clutch fork, which is automated outside of the housing which means even the release bearing is the same in MT and AMT vehicles.


Mechanically its pretty easy to do so, but electronics part will be pretty tricky. The AMT controller(TCM) has an acceleration request mechanism with the ECM. To ensure things are fine in such a mechanism, the ECM might have strict fail safe mechanisms to trigger when communication with the TCM is lost or if TCM is not reporting normal working. This will definitely throw up error codes being the least and can even put the car into Limp mode. Hence, if there is a way to emulate the TCM after removing it, then it would be good. Else you will not get the desired results.

Somewhere else you had mentioned about the TCU recognising the bite point of the clutch.

Question is how does it hold the clutch just off the bite point. With a diaphragm (instead of coil springs) actuating pressure alone is not going to accurate enough. And since there are no sensors for fork travel, no help from there either. So how does it do it?

Regards
Sutripta

The TCU can recognise the position of the clutch. This can be visible through diagnostics. As you correctly said, there is no sensor as such which senses the position of the fork. My bet is that the pressure inside the clutch actuator solenoid is what is used as a reference to approximate where the clutch position is. Which also means, there is no value for clutch position sensor data, like percentage or distance etc. It is represented as an integer which is something like 790-810 at the bite point, 1200 when fully released and between that during creep. Hence, since the estimation of clutch position is done indirectly, the control is also not accurate, which again is one of the causes for the judder. Continuing my research, I will try to log the clutch position during judder, to check if it stays at one value or changes/fluctuates.
Now if I only had access to the software, I could probably rewrite it :D

The reason why diaphragms have essentially replaced coil springs is also the reason why actuating pressure as an implied value for displacement is going to cause problems. Check out the force - displacement curves for a diaphragm.

Regards
Sutripta

I would like to mention that I successfully completed Pune-Goa-Pune trip in my 750 kms clocked Celerio AMT without using MT even in ghat sections a year back. Since than, I became a fan of MSIL AMT. Hope this feedback helps the prospective buyers.

I recently went on a long drive of around 1500km, the first time in my Celerio. The drive was pretty uneventful and since we were only two in the car, it was more or less a GoKart and I traveled around a circuit covering the Bangalore - Pune highway till Haveri, then winding roads to Gokarna, the coastal route till Baindoor, Agumbe ghats to Chikmagalur and then back home. The manual mode was used only when I wanted engine braking and while climbing a steep slope in Gokarna. Rest was all done in D itself. Even in the hairpin bends of Agumbe, the car pulled effortlessly though there were some cars stuck basically due to lack of skills when driving uphill. Maybe the first and the last time I would be driving the Celerio for so long but I can definitely rate it better when it comes to highway manners compared to the Hyundais, WagonR, Kwid and the likes.

Hello All

This post may not be entirely regarding AMT but thought of posting it nevertheless. I own a WagonR Vxi+ AMT ( stingray ) bought in August 2018. So far the car has run 5000 kms and works as expected. 100% city usage in peak traffic. Now i am curious to take her on the highway. This is not on a regular basis but just once for about 250 kms to see how the vehicle performs. Is there anything to watch out for other than checking oil levels and tyre pressure. The reason i ask is because this is my first AMT vehicle and I have heard of handling issues with the Wagon R on highways. I must admit the AMT is well matted on this car. A slight lag in 1st gear but as the levels climb its smooth sailing. The car still feels tight . I also drove my cousins celerio AMT which has done almost 20k kms. The engine and gearbox have really opened up and seems to literally fly.

Thanks in Advance:)

Nothing in particular apart from the regular checklist before driving, usually mentioned in the owners manual. As long as the car is mechanically fine, just fill the tank and just enjoy the drive. Get used to the cars behaviour before pushing it. Being a tall boy and small car, good to be careful and keep to speeds below 100 or max 120 kph.

Do look out for cross-winds. WagonR, with its tall boy design and light weight structure, gets impacted by cross-winds and even some extreme cases on wind-blasts of passing vehicles. That said, the car can run on the highway and at good speeds. Use the first few kms to familiarize yourself with the braking and dynamics before pushing it.

I take my WagonR on several long trips, including 1000+ kms/day and me as the solo driver. No issues so far.

Happy journey.:)

Thanks Jaggu and Ashis89 for the inputs.

I am generally a sedate driver and i dont see myself going beyond 80-90 kmph. Will take your suggestions and try out this AMT on the highway

Guys I have a Maruti Celerio AMT which I had purchased last year. From past few months I am noticing that whenever I apply brake or the car is moving slowly in traffic it vibrates. The whole car vibrates. What could be the issue. I'm asking cause this was not present earlier. Hope to hear soon.

Looks to me that two things need to checked . Brake pads and Alignment. My gut feeling is that the pads might have worn out or the alignment is off. If it were a few years old , i would have checked the tyres as well or rotated it. Axle issues are too far fetched since your car is new.

I never used an AMT car and drive a manual car with the same K10 engine. From the symptoms you mention, I can think of clutch issue. While slowing down if the clutch is not re-engaged at the right speed, the car can shudder. Similarly, at slow speeds/low rpm, poor low end torque and slipping of clutch could lead to vibration. Again, these are from my experience while driving a manual K10 powered car.

I have driven close to 40K kms in my Dzire Diesel AMT. Touch wood no problems so far. My drives include 60% city drives.

Long distances have included

Kolkata to Delhi and back
Kolkata to Vizag and back
Kolkata to Puri and back

A lot of 200 kms and back day / overnight trips

I don't think AMT cars will have any problem in highways. In fact IMHO they are most suitable for the highway travel.

It is the city travel which creates problem with the AMT unit with frequent up shift and down shift which causes clutch wear and tear and also overheating.