The 4 speed conversion cross member secret. - Page 3 - PeachParts Mercedes-Benz Forum

bgkast · #31 06-05-2008, 01:37 AM

Quote:

Originally Posted by bgkast

Anybody know what bolt #143 and the U bracket #137 is for?

I am going to put in the auto cross member this weekend and am wondering if I should make that U bracket out of my old cross member. It could be a fail safe to keep the transmission connected to the cross member in the event of the rubber mount failing.

Bajaman · #32 06-05-2008, 07:56 AM

Or use the other style mount like Winmutt is using.

winmutt · #33 06-05-2008, 09:57 AM

Quote:

Originally Posted by bgkast

I am going to put in the auto cross member this weekend and am wondering if I should make that U bracket out of my old cross member. It could be a fail safe to keep the transmission connected to the cross member in the event of the rubber mount failing.

I had this happen with the thinner mount when it wasnt bolted like that. Just get the heavy duty one, it can take the abuse and its stiffer so you get more go pedal to the ground.

bgkast · #34 06-12-2008, 01:13 AM

I installed the cross member and heavy-duty mount this evening. I had supported the transmission with a jack and it did not seem to need to be repositioned when I put the new cross member and mount in place, so I was not expecting any real change.

All I can say is WOW!!!

Not only are the vibrations all but gone, but the car is much quieter at idle and while driving. I think that the center bolt in the 240D manual mount was not allowing the mount to isolate the transmission from the body. It's like I'm driving a Mercedes now insted of a garden tractor. I still can't believe how much better it is to drive the car now.

Here are some pictures of the new mount/cross member with the old modified cross member.

#35 06-12-2008, 01:52 AM

What is it from?

bgkast · #36 06-12-2008, 02:04 AM

The cross member is from a 240D auto and the Meyle mount here: http://www.***************/search/product.aspx?sid=j1tb4uu3sgabfuvqxxaplprh&partnumber=123%20240%2025%2018

Bajaman · #37 06-12-2008, 06:22 AM

I thought I had an auto x-member lined up, but it ended up being for the manual. I can't wait to try this...

Stevo · #38 06-12-2008, 10:58 AM

Quote:

Originally Posted by bgkast

I installed the cross member and heavy-duty mount this evening. I had supported the transmission with a jack and it did not seem to need to be repositioned when I put the new cross member and mount in place, so I was not expecting any real change.

All I can say is WOW!!!

Not only are the vibrations all but gone, but the car is much quieter at idle and while driving. I think that the center bolt in the 240D manual mount was not allowing the mount to isolate the transmission from the body. It's like I'm driving a Mercedes now insted of a garden tractor. I still can't believe how much better it is to drive the car now.

Here are some pictures of the new mount/cross member with the old modified cross member.

So it wasn't an alignment problem, you just needed the extra 'beef' and rubber of the 4 point cross member?

bgkast · #39 06-12-2008, 11:00 AM

I think the trick was getting better isolation with the "heavy duty" mount.

Stevo · #40 06-12-2008, 08:14 PM

So the secret is to use the 240d "auto tranny"cross member and a new mount. I had once thought of swapping in a 617 turbo and maybe will some day, so i like too keep up. I think with fuel prices going bonkers, I'll keep my 616s for now tho.

winmutt · #41 06-15-2008, 10:42 AM

Quote:

Originally Posted by Stevo

So it wasn't an alignment problem, you just needed the extra 'beef' and rubber of the 4 point cross member?

The proper cross member is offset.

bgkast · #42 06-16-2008, 11:03 AM

The new mount made the 600 mile trip I took this weekend much quieter, until one of my front motor mounts tore through allowing the mount arm to vibrate against the body. It sounds like the car is coming apart when I shut it off and the engine gives its final shudders.

I think the problem was caused by oil on the motor mount, and the fact that it was slightly misaligned and "tweaked" for two years with the incorrect cross member in the car. The mount was only two years old.

#43 06-16-2008, 11:52 AM

Quote:

Originally Posted by bgkast

I think the problem was caused by oil on the motor mount, and the fact that it was slightly misaligned and "tweaked" for two years with the incorrect cross member in the car. The mount was only two years old.

Humm, that would make sense why the downward facing bolt of my left mount is tweaked out of alignment.

I've got a new HD tranny mount, driveshaft support bearing/mount on the way and I'm going to see about ordering a new driveshaft damper since the rubber part of the damper on my euro 300D driveshaft is cracking.

winmutt · #44 06-16-2008, 12:01 PM

LMK how things go with that, I need a new one on mine as well however iirc it was all one piece (dampener and rubber).

lutzTD · #45 06-16-2008, 12:09 PM

Quote:

Originally Posted by winmutt

LMK how things go with that, I need a new one on mine as well however iirc it was all one piece (dampener and rubber).

I pulled the damper from an SD, it helped but I still have a high frequency buzz/vibe from 1600 to 1800 rpm in 3rd and 4th. After that it is silky smooth. I ordered a new trans mount to see if it will help. I also notice it is worse in a right turn so I think the trans is rubbing somewhere. Now that its got some miles on it I will drop it for the new mount and look for rub spots. My top shift arm was one major culprit, when I bent it down it got rid of 50% of the magnitude of the buzz