By luck my neighbours car mechanic son was handy as I started to investigate a new (hopefully not death) rattle.

‘You’re not using the vehicle enough’ was his first comment as I let it idle to warm up, ‘the noise is from the dual mass flywheel’ !

An interesting explanation ensued & I admit I had used it less over last winter & spring.

I’ve just read an excellent article from the RAC explaining what a DMF is for & how it does it.

From now on the old girl will move more which is no hardship to me as it’s the smoothest handling vehicle I’ve had.

If yours is a campervan conversion take note!😂

Edited Monday at 04:43 PM3 days by Clutha

Wow!, that's Interesting, ours rarely gets used at the moment due to being busy with other things, and also the cost of fuel, but I'll have to give her a run out once a week now.

I always understood that DMFs were used in manual gearboxes and the amayama site for my 2005 shows a torque converter but nothing to indicate that the flywheel is anything other than a single mass:

Unless I am missing something of course.

TTFN

Paul

A bit more info.

Van had a spell of idleness due to battery (engine) issues, basically knackered, new one sourced from NAPA, good company to deal with, when I baulked at price compared to ’online’ they knocked £20 off!

Anyway engine noise, at first sounded like squeaky rattle more like loose sheet metal, then it changed to heavier knocking. When neighbours son came and checked he explained purpose of DMF and his proof of diagnosis was to change from neutral to drive with out letting the van move. The noise altered immediately & he was 100% convinced DMF was the issue & should ‘self cure’ with more use.

Van had good run yesterday and I’m convinced noise had reduced considerably plus it’s getting 2 hour run tomorrow so 🤞

My reading this morning indicates Toyota have used DMF’s in various models but I haven’t found reference to Alphards - yet!

Purpose of the part is to smooth out gear changes especially in automatics.

I recall being told by an Audi owner 23 years ago that his small lightweight car (can’t recall model) had constant trouble from DMF, & car was so light that when idling the single large windscreen wiper would gently rock car!