240D transmission flange - PeachParts Mercedes-Benz Forum

charlie19 · #1 11-12-2005, 05:08 PM

This is a 79 240D automatic transmission output flange ( I hope the photo uploaded OK). Does any helpful soul out there know the best way to get the nut off? Special tool? Pound it with a cold chisel?
By the way, this is what happens when one of the flex disc bolts comes loose.

grimgaunt · #2 11-12-2005, 09:47 PM

first one I have seen like this in almost 30 years, usually they are a 30 spline nut on the o/p shaft.

The socket to remove them is common to MBs, BMWs and a few other Euro makes

This almost looks like a jeep Dana44 locknut (axle)

samiam4 · #3 11-12-2005, 09:57 PM

You can make one from a socket with a die-grinder.

Simply measure the OD needed find a suitable socket, mark and hogout the metal in between the 4 points.
Or you can buy a special socket on-line.

Michael

t walgamuth · #4 11-13-2005, 04:29 AM

you are lucky you stopped and checked it when you did.

that looks really nasty.

didnt you hear any "funny" noises?

tom w

charlie19 · #5 11-13-2005, 09:30 AM

Can anyone please direct me to someplace on-line that sells this socket?
I didn't hear anything unusual until a few days ago, when apparently the flex disc failed (almost) completely. It was barely holding together by some of the strands of string embedded in the rubber. Then I really didn't hear anything but rather felt the driveshaft vibrating. The flex disc had almost compltely separated into pieces, and it no doubt would have completely separated really soon if I had kept driving it.
After thinking about it, I am convinced that the flec disc was not installed properly at the factory in 79, 200K+ miles ago. The flex disc was not seated in the flange, allowing movement when it was loaded. Over the years the bolt finally sheared. This is a one family car and I know that this is the first time the driveshaft has been off.

t walgamuth · #6 11-13-2005, 12:07 PM

interesting. but really if you think about the way it is built, the odds are that the ds wouldnt actaully fall out but would ultimately just spin. which is pretty nice design.

good luck.

tom w

charlie19 · #7 11-25-2005, 10:46 AM

Ground a 30mm socket from Pep Boys to fit the slots. It still would not budge, even with a breaker bar and all of my 210 lbs behind it. I drilled it with a 1/8 pilot and then a bigger drill to come just to the threads. Then knocked it apart with a chisel.

roving benz · #8 11-27-2005, 12:18 AM

I'm a little slow on the draw here but I just did two of these last week. I tried with a punch and hammer on the notches to no avail so found and priced the socket at $65. Too much money for two uses(the new nut is 30mm 12 point) so I grabbed my dremel and ground away the locking lip and they both came loose with punch and hammer. Darn good lock that lip.
Ryan

charlie19 · #9 11-27-2005, 10:54 AM

Yes, with the lip dented in I can sleep securely knowing that the nut is on there to stay. After I got it loose, a pro mechanic told me that he had a way of using a screwdriver to loosen the dent, but I am not sure exactly how. But it surely won't budge with the lip dented in. In case anyone is interested, here is a picture of the nut after I got through with it. Also, I could not find a deep 12-point 30 mm socket for the new nut ($7 from the dealer). Sears had a 12-point but it was not deep enough. Pep Boys had a deep one (shown previously) but it only had 6 points. So I used my rotory tool and ground in the additional 6 points. It only took about 20 minutes.