occasional "clunk" on downshift (slowing)
 

My mothers (was mine) W126 has started making a clunking sound at times when it downshifts when slowing down or sometimes on light acceleration when going down a hill.

My first thought are the flex discs, but I am not familiar with these at all. Are they hard to change out, or as simple as a u-joint on a conventional RWD car?

Does it sound like its the flex disc(s)?

Thanks

Flex disk don't make noise until to late.Replace every 20 years. Clunk is a vac leak somewhere.

My flex disk did some clunking when it was bad, if I were you I would get under there and take a look before its too late.

too late? too late for what? :confused: your beginning to scare me.

its more of a slight "pop" (or a TICK) sound when it downshifts (occasionally). I have owned the car for 2 years and its always done this. Never knew there was a "too late" point.

I wonder how much is this gonna cost? My mother (55) and my 17 month old nephew has to drive this car about 250 miles per week (all highway driving). I certainally dont want to break down on them on the highway.

I cant even find "flex discs" listed at local auto parts stores. :rolleyes:

Found them on the site here... they are cheap too... over $100 for one and $64 for the other. :rolleyes: I have to take the car into the shop for some work in two weeks... maybe the MB tech and look into it.

You said to check them... how do I check them?

Get under the car and at both ends of the drive shaft that is where the flex disks are. Grab the drive shaft and turn it back and forth and watch the flex disks, too much play in them and its time to replace. Also look for cracks.

Check the rear diffy mounts.

Thanks guys... I will check or the tech we are taking it to in two weeks.

I just didnt want anything breaking and coming up through the floor boards! Someone said they could fly up into the car. :eek: