[Mark e90]

What would you say is the more robust/reliable transmission for a e90 with circa 80-90k miles manual or auto ? I notice when looking at some of the adds a lot of the manual cars will say just had clutch and flywheel done so is this to be an expected bill with a manual ? I haven't had a manual for a good few years now but i have owned 2 e90 autos which were both at around 100k when i sold them, both cars gave me no transmission problems whatsoever.

So basically what I'm asking is when buying these cars with higher millage are you better going for a manual or auto ? i suppose even if you do need to replace the clutch and flywheel its going to be a lot cheaper than an auto box rebuild right ?

[Rich_D]

A clutch & DMF will be required at higher miles, not cheap!

However the ZF box is pretty reliable, mine is on 110k miles now, had the gearbox oil & filter done a few months ago (~£300), it is lovely & smooth to drive, no concerns for me and my car is remapped too.

[DavS1]

I've hardly saw any issues with auto boxes on 3's, but many problems with manual, synchros (baulk rings), clutches, flywheels.

[E90325iM-SPORT]

I use manual gearbox on 325i with 106k and I really abuse my car . Most of the problems with flywheel is on remapped diesel cars.

[makkan00]

Originally Posted by RomanWheelman

I use manual gearbox on 325i with 106k and I really abuse my car . Most of the problems with flywheel is on remapped diesel cars.

Spot on. Remapped diesels give you issues.

If you want some fun and happy to keep some money in your pocket for repairs, then go for manual.

If you are after reliability, then boxes on Auto cars are pretty solid especially if you service them at / around 100K.

[Mark e90]

yeah now you say that it was mostly diesel models that mentioned that in their adds its a 330i or 325i I'm after.

also how much are you talking roughly to do A clutch & DMF ? i got the 6 speed zf box serviced and flushed in my range rover and it cost me £400 from mackies glasgow so considering thats what it cost just to service the auto i may consider getting the manual as thats really what id prefer, i have a real hankering for one, not had a manual car for about 5 years

[AlwynMike]

Get a manual box Mark

You know it makes sense

If you wanted a car for cheapness, you'd be in a Kia (or in a few months a Golf Diesel )

How much do you value your driving enjoyment?

I would dearly love to have a manual, but I enjoy the 335 dirty D power delivery, so I compromise with the slushbox (nice as that is at times).

Diesels hammer (literally) the dual mass flywheel, so when you change that, you do the clutch as a matter of course, and the costs go up. A nice, proper smooth petrol engine doesn't stress the DMF, so they last - some don't have them, as there is no need.

The best way to preserve a DMF is to keep the revs on - my 2005 Mondeo hack is on it's second DMF (one fitted before I bought it, and it needed one when I bought it). The engine now is never driven below 1800rpm, and often much more than that! I expect it to last well into it's 200,000 miles

Mike

[Mark e90]

Thanks for the info guys, as I said my last bmw was a 325i auto so I'm imagining by looking at the figures a 330i manual would be a different car all together with basically the same running cost ! In fact belive it or not the 330i for me is actually cheaper to insure. So for this reason even as much as I loved my 325i auto I did always grudge the fact it's wasn't either a manual or 330i

Just trying to find out roughly the cost to have clutch and dmf done so I know what I'm in for but as I said before if I went for an auto I would be planning on having the box serviced which would cost about £400 so as long as the clutch and dmf isn't majorly expensive then I would go for a manual.

anyone here know how much roughly ?

[E90325iM-SPORT]

Get 330i if you can , 325 must be really high reved to get any power out of it

[Mark e90]

That's the plan mate although I just find with these cars you sometimes need to compromise as there isn't many about, hence the reason I got a 325i auto last time round. However I have spotted a nice looking 330i manual I am compromising on this one though as it was a e91 I was originally after but that is another story altogether ! they seem extremely rare and as a result expensive. .. I'm just trying to find out what your talking for clutch and dmf before I pull the trigger.

[Rally_chris]

Take a look at my ad in the classifieds if you fancy a manual 330i touring, Mark.

http://www.e90post.com/forums/showth...1#post18647721

[AlwynMike]

Mark

Nowhere near the same, but the Mundane-o clutch plate, cover, thrust and DMF was £700 fitted. It's not just a gearbox out job on the Ford, you have to drop the subframe.

Mike

[Mark e90]

Originally Posted by AlwynMike

Mark

Nowhere near the same, but the Mundane-o clutch plate, cover, thrust and DMF was £700 fitted. It's not just a gearbox out job on the Ford, you have to drop the subframe.

Mike

so this price was for a job done on a ford ? i take it its likely to be more expensive on an e90 ?

[makkan00]

Originally Posted by AlwynMike

Get a manual box Mark

You know it makes sense

If you wanted a car for cheapness, you'd be in a Kia (or in a few months a Golf Diesel )

How much do you value your driving enjoyment?

I would dearly love to have a manual, but I enjoy the 335 dirty D power delivery, so I compromise with the slushbox (nice as that is at times).

Diesels hammer (literally) the dual mass flywheel, so when you change that, you do the clutch as a matter of course, and the costs go up. A nice, proper smooth petrol engine doesn't stress the DMF, so they last - some don't have them, as there is no need.

The best way to preserve a DMF is to keep the revs on - my 2005 Mondeo hack is on it's second DMF (one fitted before I bought it, and it needed one when I bought it). The engine now is never driven below 1800rpm, and often much more than that! I expect it to last well into it's 200,000 miles

Mike

Mike
Are you saying that cars have to be driven on high revs to keep DMF safe?
And is that applicable on diesels?
Sorry for knoob question but I always thought that driving manuals on lower rpms is relatively safer.

[AlwynMike]

Originally Posted by makkan00

Mike
Are you saying that cars have to be driven on high revs to keep DMF safe?
And is that applicable on diesels?
Sorry for knoob question but I always thought that driving manuals on lower rpms is relatively safer.

Most definitely keep the revs up Sam,

The whole point of a DMF is to make the driving experience smoother, particularly on lower revving engines like a diesel. They work hardest at low revs and when pulling off from stationary. At higher revs they do minimal work.

To dampen out the vibes on a diesel, a relatively heavy flywheel is needed, but this of course affects acceleration, economy etc. Some boffin thought out the dual mass flywheel to try and gain the best of both worlds. It works, as any diesel driver will tell you, but they aren't the most reliable things. Now, you're not going to break down as a direct consequence of a DMF failure, you will be uncomfortable with the noise at tickover and pulling off long before that happens. The Ford DMF failures that lead to breakdowns are due to the build up of metal filings within the clutch housing. These contaminate the starter to the extent that the engine won't crank over.

I would not expect any modern diesel to be without a DMF (including light commercial vehicles). They are not as prevalent on petrol engines which are naturally higher revving and smoother.

Auto's are also fitted with DMF's, but as you cannot labour an Auto, they are far less likely to be stressed like one fitted to a Manual. Think if you are in traffic, pottering along at 1500rpm....in a Manual, you put your toe down to keep up with the white van in front, and you get lots of vibrations from each firing occurence, multiplied by the time you have your toe down. Of course, in this situation, in a Auto, the gearbox slips, so the engine revs rise, so the vibrations, although at a higher frequency, are less violent, so lessening the stress on the DMF.

The DMF is effectively a loose object in your drivetrain, and any loose object will wear with all the torque reversals it encounters - an extreme description perhaps, but true.

There are solid flywheels available to replace DMF's, and these are considerably cheaper to buy. However, there are many stories about people putting in solid flywheels - certainly in Fords, and particularly in Transit's - then a year or so later, they need a new crankshaft, as the resultant increase in vibration has snapped it. Not nice.

As in all things, as more DMF's fail, the cheaper they are to buy, as the manufacturers can then gain an economy of scale. A quick look at EuroCarParts shows a Mondeo DMF for under £200, one for a 2 litre E90 for under £300. Plus a clutch if you're sensible, say the same cost again for both. Then at most a day's labour at your favourite Indy.

As a general rule, most Turbodiesels develop their maximum torque at around 1700-1900rpm, so this is (broadly) the most efficient, and most DMF's will be locked up by this speed. My Mundane-o was almost embarrassing (well, it is a Ford!) up to 1300rpm when I bought it - it sounded awful. (And no, I didn't buy it cheap, I bought it very cheap!!). I did run it for over a year with the godawful racket from the DMF - now it's just the pistons that rattle!

Mike

[makkan00]

Originally Posted by AlwynMike

Most definitely keep the revs up Sam,

The whole point of a DMF is to make the driving experience smoother, particularly on lower revving engines like a diesel. They work hardest at low revs and when pulling off from stationary. At higher revs they do minimal work.

To dampen out the vibes on a diesel, a relatively heavy flywheel is needed, but this of course affects acceleration, economy etc. Some boffin thought out the dual mass flywheel to try and gain the best of both worlds. It works, as any diesel driver will tell you, but they aren't the most reliable things. Now, you're not going to break down as a direct consequence of a DMF failure, you will be uncomfortable with the noise at tickover and pulling off long before that happens. The Ford DMF failures that lead to breakdowns are due to the build up of metal filings within the clutch housing. These contaminate the starter to the extent that the engine won't crank over.

I would not expect any modern diesel to be without a DMF (including light commercial vehicles). They are not as prevalent on petrol engines which are naturally higher revving and smoother.

Auto's are also fitted with DMF's, but as you cannot labour an Auto, they are far less likely to be stressed like one fitted to a Manual. Think if you are in traffic, pottering along at 1500rpm....in a Manual, you put your toe down to keep up with the white van in front, and you get lots of vibrations from each firing occurence, multiplied by the time you have your toe down. Of course, in this situation, in a Auto, the gearbox slips, so the engine revs rise, so the vibrations, although at a higher frequency, are less violent, so lessening the stress on the DMF.

The DMF is effectively a loose object in your drivetrain, and any loose object will wear with all the torque reversals it encounters - an extreme description perhaps, but true.

There are solid flywheels available to replace DMF's, and these are considerably cheaper to buy. However, there are many stories about people putting in solid flywheels - certainly in Fords, and particularly in Transit's - then a year or so later, they need a new crankshaft, as the resultant increase in vibration has snapped it. Not nice.

As in all things, as more DMF's fail, the cheaper they are to buy, as the manufacturers can then gain an economy of scale. A quick look at EuroCarParts shows a Mondeo DMF for under £200, one for a 2 litre E90 for under £300. Plus a clutch if you're sensible, say the same cost again for both. Then at most a day's labour at your favourite Indy.

As a general rule, most Turbodiesels develop their maximum torque at around 1700-1900rpm, so this is (broadly) the most efficient, and most DMF's will be locked up by this speed. My Mundane-o was almost embarrassing (well, it is a Ford!) up to 1300rpm when I bought it - it sounded awful. (And no, I didn't buy it cheap, I bought it very cheap!!). I did run it for over a year with the godawful racket from the DMF - now it's just the pistons that rattle!

Mike

Mike
Very useful post.
I tend to drive diesel on low revs thinking that its better for mpg and less stressful on DMF and clutch.
Sounds like I should keep the revs up.
TA.

[AlwynMike]

Originally Posted by makkan00;

Mike
Very useful post.
I tend to drive diesel on low revs thinking that its better for mpg and less stressful on DMF and clutch.
Sounds like I should keep the revs up.
TA.

Sam,

My brother did some unscientific tests on his Jag X type oil burner.
Repeated A-road cross country 100 mile journeys at 50-55mph, with the odd overtaking blat. The Jag would only just pull 50mph in top gear. The fuel consumption was exactly the same if he cruised in 4th gear, 5th gear or 6th gear.

Apologies to Mark e90 - a little off topic!

Mike

[Aragorn30d]

Clutch costs are probably pretty similar between a mondeo and a 3 series tbh.

They're both mass produced cars and the parts are common which keeps prices down.

A quick look suggests a 330d clutch is £150ish and the flywheel is around £300. Fitting i'd expect to pay around £300, so much the same as the 700quid quoted for the mondeo.

DMF's are used on almost all modern cars, petrol or diesel. They do an excellent job of reducing NVH and everyone expects low NVH from modern cars. On lower powered cars with petrol engines, often they will remove the springs from the clutch plate and rely solely on the DMF to provide that "spring", as the lighter clutch disk makes for an easier life for the gearbox syncros, which inturn means shifting is smoother etc.


As for running an engine at low revs its sorta complex issue. Everyone loves to talk about torque, but a given road speed requires a certain amount of power to maintain, and a given amount of accelleration requires a certain amount of power to achieve. Power is Torque x RPM. So if your at 1500rpm, you need twice the torque you need at 3000rpm to produce the same power. The clutch and gearbox deal with torque, so if your driving around at low RPM's with lots of torque, the clutch and transmission are seeing larger loads. If you slow things down, you can imagine that at 1500rpm, the explosions going off inside each cylinder are twice as powerful than they would be at 3000rpm, because you need to achieve the same amount of work done, and those bigger explosions impart larger shock loadings on the transmission components.

An analogy might be hammering a nail in. You can use a really big hammer, and whack the nail in with one hit (big torque, low RPM). Or you can take a much smaller hammer and whack the nail in with three or four hits (small torque, high rpm). the end result is the same, but the forces involved are quite different.

A given engine will also have a "map" of efficiency which plots torque against RPM against fuel consumption. Most engines this peaks at the lowest RPM where the engine can generate peak torque, usually somewhere around 2000rpm on a diesel, at or very near to full throttle. This is because its the point at which the losses are the smallest for the given output. Run the engine slower or faster than this point and it will be less efficient. Run it at a smaller load point (ie less throttle) it also gets less efficient. High engine speeds tend to hurt more than low ones though.