Needing someone to help with w124 transmission vac/other issues in ohio

[1977busman]

Ok ive gotten to the point that my time is worth more than my money, and I am looking for someone preferably within 1-2 hours of central ohio that would be willing to work on my 300d's transmission.
Here is some back ground:
-very slight flare when I got bought it 6500miles ago
-Decided to replace vaccum lines and connectors to help flare
-Flare got much worse after step above^^
-Now flares 150-300rpm on some shifts and others it clunks in the rear or shifts very hard.
-Somedays are MUCH worse than others for no apparant reason.
-Adjusted the modulator on tranny some, but without much effect.
-I have the opportunity to buy a 150k-ish miles tranny off ashedd if all else fails, but I want to make sure that its not just an adjustment, that could fix the issue without a tranny replacement.

The only part that confuses me is that some of the shifts flare alot, and others clunk/shift hard. In my past experience I have had either all hard shifts or all flaring shifts.

Im done messing with it, and am hoping someone could go through everything and either A.) fix the issues or B.) confirm that the replacement is needed.
So if you are willing to do this or know someone that is let me know and name your price...
Thanks,
Zach

[chazola]

sounds obvious, but have you changed the fluid & filter? Also you say it clunks in the rear end- these are probably your diff bushes- mine used to do that and stopped after replacement. My transmission also shifts smoothly (original at @219k) after this and fresh fluid & filter and no modulator adjustment. Make sure you check all vacuum connections too.

[bamba]

This may not be what you're looking for, but there is an w124 with a manual tranny at Pull-a-Part Cleveland. Odo shows only 136k. Could be a pretty nifty solution.

[1977busman]

[QUOTEsounds obvious, but have you changed the fluid & filter? Also you say it clunks in the rear end- these are probably your diff bushes- mine used to do that and stopped after replacement. My transmission also shifts smoothly (original at @219k) after this and fresh fluid & filter and no modulator adjustment. Make sure you check all vacuum connections too. ][/QUOTE]

Differential mount and bushings were replaced sometime between 130-146kmiles.
Previous owner did a fluid and flush around 130k, and I did a flush and filter 700miles ago. The fluid was clear and free of debris. It had no affect whatsoever on shifting aftwerwards.

I have a perfect 15hg going to the trasmission, and it goes down to about 0hg with full throttle.

The clunking only happens when it gets held out in one gear just under 2000rpm. If I get into the throttle more, it shifts firmly. But if im trying to drive conservatively in town (70% of my driving) it clunks around 1800rpm when it cant decide if it wants to shift or not.
The flaring seems to happen mostly in 2-3 and 3-4.

This may not be what you're looking for, but there is an w124 with a manual tranny at Pull-a-Part Cleveland. Odo shows only 136k. Could be a pretty nifty solution.

This is what I would like to do, I looked into this with ashedd and was going to have him put it in. But I just dont want to spend that much on it, when I can get ashedd's transmision and even have it rebuilt and installed for much less than what a total 5speed swap would cost in the end.

[DieselPaul]

My rear diff bushes were shot by 150k and replacing them made a huge difference.

Is your car powerful enough? My out of adjustment Alda was making my car shift like a dump truck. Adjusting the vacuum controller on the side of the injection pump on a friends 350SD got rid of flaring.

[sixto]

Your problem might be as simple as a leaking modulator cap; the rubber cap over the T-handle used to adjust modulator pressure. Mind you, I'm throwing it out there for lack of a good answer.

Sixto
87 300D

[gsxr]

DP and Sixto have good points. Make sure the vac modulator is holding vacuum and not leaking (test with MityVac). And if the IP is too lean, so you're using too much throttle to get 'normal' power delivery, the shifts will always be harsh. Conversely if you've removed the ALDA, you could get the opposite, some flaring due to too little throttle travel. It's odd that you have some flaring and some harsh shifts.

What fluid did you use when you changed fluid/filter (specifically, was it Dexron II/III spec, or Dexron VI?) and did you drain the torque converter to get ~99% of the old fluid out?

Could be a faulty vacuum modulator, after the items above, I'd probably replace that before considering a transmission replacement. Bummer you're not closer, I have a good used 87 300D trans collecting dust in my shop.

[1977busman]

Your problem might be as simple as a leaking modulator cap; the rubber cap over the T-handle used to adjust modulator pressure. Mind you, I'm throwing it out there for lack of a good answer.

I replaced it, and my modulator holds vacumm

My rear diff bushes were shot by 150k and replacing them made a huge difference.

Is your car powerful enough? My out of adjustment Alda was making my car shift like a dump truck. Adjusting the vacuum controller on the side of the injection pump on a friends 350SD got rid of flaring.

The car only has 152,700 now, so the bushing should have been replaced within the last 20k miles or less according to maintenance reocrds. But I wont rule this out if nothing else fixes it.

I have not adjusted the vac controller on the side of the ALDA, but will look into it, I just am short on time at the moment.
ALso the car is way faster than any diesel benz ive owned and last 0-60 I did was right at 12secs.

Thanks for the replies, Ive just been really frustrated with this lately, and being a senior in high school, while taking all of my classes at a local university, and working 30hours a week is starting to get to me. I would just like to have one mercedes that shifted properly. Im willing to invest in this one quit a bit because she needs so little, aside from the shifting issues.

[sixto]

I had the same low speed clunk until I replaced the diff bushings and, oddly enough, tightened the Bowden cable. I still get the clunk on a rare occasion but now muffled by better bushings. Usually happens when prowling for a parking spot, right? My guess is not enough throttle input or internal pressure to nudge the tranny out of first gear. Not a vacuum issue.

Sixto
87 300D

[sixto]

Come to think of it, tightening the Bowden cable might ease the flaring because you'll shift under more throttle and therefore with less vacuum. It's a mask but we'll know who's behind the mask

Sixto
87 300D

[gsxr]

Yeah, next step would be to adjust both the Bowden cable and also the VCV per factory procedure, and see what that does:

VCV adjustment (note: engine does not have to be running to do this) :
http://www.w124performance.com/docs/mb/transmission/trans_VCV_adjustment.pdf

Bowden adjustment:
http://www.w124performance.com/docs/mb/transmission/trans_Bowden_adjustment.pdf


0-60 in 12 seconds is what it SHOULD do, nice to hear the car has normal power...

[1977busman]

Usually happens when prowling for a parking spot, right?

Spot on...

Yeah, next step would be to adjust both the Bowden cable and also the VCV per factory procedure, and see what that does:

VCV adjustment (note: engine does not have to be running to do this) :
http://www.w124performance.com/docs/mb/transmission/trans_VCV_adjustment.pdf

Bowden adjustment:
http://www.w124performance.com/docs/mb/transmission/trans_Bowden_adjustment.pdf


0-60 in 12 seconds is what it SHOULD do, nice to hear the car has normal power...

Thanks Ill try to get a start on this over the weekend.

[bamba]

Originally Posted by 1977busman

This is what I would like to do, I looked into this with ashedd and was going to have him put it in. But I just dont want to spend that much on it, when I can get ashedd's transmision and even have it rebuilt and installed for much less than what a total 5speed swap would cost in the end.

Understandable. I was surprised to see it there, and hope that someone can save it from the crusher. Pull-a-Part is relatively cheap. You could probably walk away with the tranny, driveshaft, diff, shifter, all the odds and ends etc. etc. for $200-300. Half of the time the girls working the register don't know what they're doing anyway...

[Oldwolf]

Originally Posted by gsxr

Yeah, next step would be to adjust both the Bowden cable and also the VCV per factory procedure, and see what that does:

VCV adjustment (note: engine does not have to be running to do this) :
http://www.w124performance.com/docs/mb/transmission/trans_VCV_adjustment.pdf

Bowden adjustment:
http://www.w124performance.com/docs/mb/transmission/trans_Bowden_adjustment.pdf


0-60 in 12 seconds is what it SHOULD do, nice to hear the car has normal power...

The 602.962 engine is not discussed in the Bowden Adjustment pdf. Will the 603.96 procedure work instead? Thanks.

[sixto]

Yes.

Sixto
87 300D