2010 Diesel Drivetrain shudder

skipalami · Post by **skipalami** » Tue Jan 18, 2011 5:43 pm

I am starting a new thread based on a topic being discussed under the DPF (particulate filter thread).

skipalami · Post by **skipalami** » Tue Jan 18, 2011 6:03 pm

So, here is the problem.

2010 Diesel Outback. The problem happens in a high gear. 4th, 5th or 6th and on an incline , even a gentle one, at about 1900 to 2300rpm.

When the shudder starts, it starts slowly and builds until the whole car shakes. To do this it needs the incline to be long and continuous. If the road crests over and the load on the engine is removed, the shudder will subside.

The other way to get the shudder to stop is to change down to at least 4th.

The dealer is being really good and trying to help me out as much as possible. They are as perplexed as I am. The user "Doubtback" is also getting the same problem. The car feels like it has the torque to give, however the shudder (that will make your teeth chatter if you push it) makes you back off.

A new car shouldn't behave like this, and my service centre agrees.

Doubtback · Post by **Doubtback** » Wed Jan 19, 2011 10:48 am

My experience is very similar to skipalami - everyone in the vehicle notices the shudder and I agree a new car should NOT behave in this way. I have had the problem occur even in 3rd gear once - but always in that rev range of 1900 - 2300. The issue for me has even occurred a couple of times on a flat piece of road - but usually an incline - the last time it happened(in 4th on an incline) instead of changing down a gear I accelerated - the problem subsided once I went beyond the 2300 rpm. I was towing a trailer last week that had a ride-on mower in it which is not too heavy - the problem manifested itself even more readily on an incline. This is not a lack of power or torque issue or even a gearing issue (my dealer initially said it was the engine labouring and I was running in too high of a gear - nonsense!) I was told not to run below 1800rpm in 4th which I don't. The latest explanation from Subaru (after I presented them with documented evidence of each time this happened over a month) is that it is a Diesel Particulate Filter issue (see comments in that thread) - the explanation is that the shudder happens when it is doing a 'burn' of excess soot in the filter (the user manual tells you how to do a manual regeneration if the Diesel Particulate filter warning comes on - my warning light has never come on(p3-37) ). However, when they connected the computer they told me that each burn took only milliseconds to do, so to me that is not what causes the shudder as the shudder continues to happen until you change the engine revs.

Mess · Post by **Mess** » Tue Jan 25, 2011 10:25 pm

I have exactly the same problem. It started at around the 13,000km mark. Driving up inclines at highway (ish) speeds (80-100+ kph), the entire car shudders violently and the engine torque vanishes. Changing down to 5th or even 4th is the only solution.

This is NOT a case of the engine being over laboured. I'm talking about an incline that any modern car can easily take in top gear. In the Forester, on one part of my commute home, there is a long incline where the speed limit rises from 80-100kph. I have always just rolled it on in 6th and it lopes up to 100 no problem. Now, it will accelerate to 100 or just beyond and then start to shudder and lose all power.

Today, I accelerated gently to 100kph in 5th on this incline. Once at about 103kph, I shifted to 6th and set the cruise control. After about 7 seconds, the shudder started and the engine lost power. I had to go to 4th gear to cure it. Considering this is a torquey turbo diesel engine and the problem is happening at or near the point of peak torque, there's no way in hell I'll accept the dealer telling me that I shouldn't be driving it in top gear.

I bought this car specifically to lope along at 1500 - 2500 rpm, sipping fuel and riding the torque. if I can't do that, I'll be one very unhappy customer.

Booked into the local dealer for 7 Feb (soonest they could fit me in). Hopefully a resolution can be found. I'm starting to feel the first tinges of buyer's remorse. Perhaps we should have got the Skoda Scout...

I'll post when I have more info after the 7th.

Gannon · Post by **Gannon** » Wed Jan 26, 2011 6:39 am

Another forum member suggested that the engine may be spending too much time at low rpm and low load and not generating enough heat to burn off the soot in the DPF

Maybe try flogging the engine for a minute or two just before the slight incline and see if it happens again

Id really like to have a drive of the new diesel engine, just to see what its like.

littlewhiteute · Post by **littlewhiteute** » Wed Jan 26, 2011 7:05 am

I'd say it's a programming issue.

Surely it happens on enough cars for Subaru to log some data on one of their own to find the fault.

I've never heard of DPFs causing this shudder.
As you boys above have mentioned, it occurs only in a narrow loaded low rpm band.

Subyroo · Post by **Subyroo** » Wed Jan 26, 2011 10:19 am

Could it be a different manifestation of the DMF (Dual Mass Flywheel) if indeed they are fitted to the Diesel's?

I have no idea what sort of clutch/flywheel are fitted to the diesel's just throwing out a suggested area to look at or maybe even the center bearing.

P.S. How do we avoid this, it pisses me off:

The message you have entered is too short. Please lengthen your message to at least 1 characters.

steptoe · Post by **steptoe** » Wed Jan 26, 2011 2:59 pm

Would you try doing a manual regeneration as manual describes , before you hit the stretch of road that can cause the shudder. Mate found an Escabune that had been into dealer over 100,000km with common complaint of an intermittent shudder. May have been bad day at factory coz a rear diff mount bolt was loose.Yours is definitely engine as you lose power/torque.

Leaving a vehicle with a dealer until it is sorted works well especially if you get their best demo car.

At least Mess being able to get rid of symptoms on shifting down a gear must help diagnosis, so too an exhaust analysis on a dyno. Make sure mechanic doing problem solve knows what road you use to get crap happening.
Is it fuel quality? That is a good one to blame a third party !

Compare notes, contact fuel supplier head office asking of a grade or standard their product complies with to rule it out

baitman · Post by **baitman** » Wed Jan 26, 2011 7:31 pm

i would tend to agree with subyroo. i think but dont take my word for it check with subaru but i was under the impression that the gen 5s have gone back to a solid mass flywheel. the previous model had a dual mass flywheel which caused subaru a lot of warrenty issues the dual mass is a plantery gear system flywheel which took the shudder out of the drive train. they are a crap thing and subaru replaced a lot of them under warrenty there are also very expensive so solid mass kits usually go in when the clutch needs doing. so if you have a solid mass flywheel and driving with maybe not enough revs in the right gear you will get a shudder throught the car . nothing to worry about they have just changed a passenger car into a truck with less moving parts between the rear main and the clutch plate. i have just changed my dual mass flywheel to a solid mass. and i have noticed when i go around a small round-a-bout in 3rd with not enough revs the whole car shudders as i did not before this effect was to be expected the exedy kit which i used explained in great detail how the car would sudder through the drive train once a solid mass was used , so check with subaru and see if you have a solid mass.

littlewhiteute · Post by **littlewhiteute** » Thu Jan 27, 2011 7:33 am

Ok, so is this a vibration (driveline or other), or a fueling misfire?

steptoe · Post by **steptoe** » Thu Jan 27, 2011 12:14 pm

Does not sound like anything is broken or loose, more an an engine fueling glitch and can only guess it is new to Subie owners as is Diesel, common rail fueling more like petrol efi engine management and that comp ratio must be typical Diesel in area of 22:1 so any disharmony likely to be double of that in a petrol efi system with same or similar fault

Doubtback · Post by **Doubtback** » Fri Jan 28, 2011 7:23 pm

Quick update - Just got back from a 2 hour trip and the shudder happened for the first time going down a decline - 5th gear 2000 rpm. NOT Happy. Will be very intersted to hear what Mess's dealer has to say...

littlewhiteute · Post by **littlewhiteute** » Fri Jan 28, 2011 7:32 pm

Doubtback wrote:Quick update - Just got back from a 2 hour trip and the shudder happened for the first time going down a decline - 5th gear 2000 rpm. NOT Happy. Will be very intersted to hear what Mess's dealer has to say...

Ahh, interesting.

So not necessarily always a loaded condition, but the common is around 2000rpm.

Can I ask were you doing higher rpm say 2500+ and while coasting down to 2000 the shudder started?

This type of info could be helpful to the dealer as well.

skipalami · Post by **skipalami** » Sun Jan 30, 2011 10:04 am

Downhill?!. Thats is a new symptom.

My thoughts... the first ECU had DPF management issues (not enough regens)so they released a new software version which has ended up having these shudder issues. People who got their 2.0D's with the early ECU's don't seem to complain of this shudder, although I don't have any statistical evidence of this.

I did find one person in the UK who complained about this kind of shudder in a 2010 Legacy, and they indicated the problem may have still been DPF related as the engine was perfoming too many regens on the DPF and loading the engine up with too much fuel and clagging up the DPF instead of clearing it.

Personally, I am doing everyting in my power not to excite this vibration as I think it subjects the rest of the drivetrain to unnecessary wear. As soon as I detect it has started, or I think the approaching road will trigger it, I drop a cog or two to get well away from 2000rpm. I shouldn't have to do it (obviously) however I am trying to baby this problem unil it is resolved properly.

I am in constant contact with my service centre and I must state that my service manager and techs have been awsome in trying to nut out this problem. They are really making every effort to think outside the box on this one.

Like I said early on, I think this is the pointy end of a bigger problem and we are some the first ones to uncover and hence deal with this gremlin.

I have no doubt that it will eventually be fixed.

Doubtback · Post by **Doubtback** » Mon Jan 31, 2011 10:20 am

Can I ask were you doing higher rpm say 2500+ and while coasting down to 2000 the shudder started?

No - I was accelerating away from an intersection and going down an incline and slipped it into 5th - I couldn't believe it when the sudder started as it was the first time in 22,000k's that it had happened going down an incline..

MY11OBD · Post by **MY11OBD** » Fri Feb 04, 2011 7:45 pm

I have had my MY11 Diesel for 4 months now with 8300km on the clock. Only recently have noticed on londer inclines around 80-100 km between 5th and 6th gear there is an almighty shudder. This rattles the things I have in the boot like an earth quake just hit. Jumping back into 4th corrects this.

The rpm would have been around the 1800 - 2100 mark.

Could this be a fuel pump issue?

I have also had one issue with the DPF light comming on, but since changed to changing gears around 2000 rpm this has not happend and its been at least 3000km since it did.

Any more news on others who have had issues?

littlewhiteute · Post by **littlewhiteute** » Fri Feb 04, 2011 8:22 pm

It won't be a fuel pump issue.

Does this vehicle come as an auto, or manual only?

Does the engine come as VNG turbo only, or non-turbo as another option?

And can all concerned list the fuel (supplier) you are using?

MY11OBD · Post by **MY11OBD** » Sat Feb 05, 2011 7:26 am

Hi Gary, thank you for your interest...

I have an Outback Diesel, 6 Speed Manual, Diesel only sourced from SHELL or COLES EXPRESS OUTLETS within 50km of Melbourne CBD.

Any help or suggestions appretiated.

MY11OBD · Post by **MY11OBD** » Sat Feb 05, 2011 7:27 am

Oh not sure what a VNG Turbo is but I have a turbo diesel.

Thanks

littlewhiteute · Post by **littlewhiteute** » Sat Feb 05, 2011 7:43 am

A few cars these days have variable nozzle (VNG).

They alter the attack angle of the exhaust hitting the turbine wheel with a set of linked vanes which are ECU stepper motor controlled.

They run no normal wastegate, boost pressure is electronically limited by the ECU.
Allows faster spool up of turbo for low speed torque.