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1983 300TD, 115,000 miles. Anthracite Gray
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Discussion Starter #1
Hello all. A few days ago I posted here about my recently acquired '83 300TD's transmission issue: Apparently I'm missing first gear.

I got some helpful replies, for which I am grateful. But, after speaking to my local independent Mercedes mechanic, I wanted to ask another question or two. For an overview, please see my earlier thread. This mechanic already checked out the car and gave it a clean bill of health. They didn't mention any missing gear, and I didn't notice it until later. (I knew it was slow off the line, but I figured that was just how they drive.)

In a nutshell, my mechanic is skeptical of my diagnosis. He thinks I have a first gear but that I'm not detecting the 1:2 shift because it happens very early and is subtle. When I mentioned, based on information from that earlier thread, that it was my understanding that with the car in "L" the shift would occur at the top of the range, he said, "n-o-o-o-o, I don't think so."

I've gone searching for a 1-2 shift -- listening for shifts, watching the tachometer, observing in L (up to high RPMs), S, and D. I've adjusted the Bowden cable to try to get a firmer, higher-rpm shift so that the 1-2 would be harder to miss. And I've detected nothing.

How likely is it, do you think, that there's a first gear in there that I just can't detect. (I'm very skeptical myself.) And how can I be absolutely sure?

Thanks,
Jim
 

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W-1-2-3 Go!
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Try this.

On an empty road, put the car in D and let off the brake. Do NOT touch the accelerator. It should creep slowly in 2nd.

Shift to L without touching any of the pedals. You should feel it shift down to FIRST.

55mph should be right about 2500RPM in top (4th) gear.

The gear that is mostly not felt is 2nd gear (in our 83 anyway). This is because shifting to L will place the car in FIRST. Second gear is high up in the RPM as mentioned earlier. Third can be accessed by shifting to S manually. And of course fourth is in D.

If you want to try feeling for second, shift the vehicle to S at LOW speed to access 3rd gear, and under certain situations stab on the pedal to downshift to 2nd. Only certain situations allow this. Sometimes mine does, sometimes 3rd is enough. Almost always it might not shift down since the engine has sufficient torque to use 3rd gear.
 

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1983 300TD, 115,000 miles. Anthracite Gray
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Discussion Starter #3
MBeige,

That's a clever test, thanks! Can't wait to try it. Unfortunately I'm traveling now and won't be home 'til Saturday. I'll report back.

Best Regards,
Jim
 

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1983 300TD, 115,000 miles. Anthracite Gray
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Discussion Starter #4
Test is done -- no first gear

OK, so I did that test -- put the car in P, foot on break, shifted to D, removed foot from break (not touching the accelerator pedal), allowing it to creep forward. Then -- still without touching the accelerator pedal -- I shifted to L. The car should have started off in 2nd (since I had not touched the accelerator pedal, and then it should have shifted into 1st. Correct?

Well, nothing happened. It didn't downshift. I tried it half a dozen times.

So, no first gear. What now? Valve body?

Thanks,

Jim
 

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2001 Volvo V40
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Do you know the number of the transmission? it is above the oil pan on the passenger's side.

Either it was in first gear already or something more serious is wrong.
 

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1983 300TD, 115,000 miles. Anthracite Gray
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Discussion Starter #6
Do you know the number of the transmission? it is above the oil pan on the passenger's side.

Either it was in first gear already or something more serious is wrong.
Well, I've also done the experiment of starting it out that way and running it up to 4500 rpms -- in L. And I've never managed to get it to shift.

So

* Starting in D without touching the pedal, then shifting to L, there's no shift.

* Starting in L, there's never any shift.

* From stop up to about 80, I've never counted more than 2 shifts.

So I think I'm missing 1st gear.

Any thoughts on what that "something more serious" could be?

Thanks,
Jim
 

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2001 Volvo V40
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What speed where you doing at 4500 rpm in L?

I'm thinking that maybe a three-speed automatic (from a 8-cylinder W116) was installed (that is why I asked for the number) or that something is damaged inside the transmission so that it doesn't go into first gear.
 

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What's the condition of the bowden cable? Is it adjusted taut, relaxed or tight?

If it is taut, it should shift normally through the gears.

If it is relaxed, it will shift very softly and early.

If it is tight, it will shift late and hard.

It is possible your cable is also adjusted too relaxed.

It takes quite a bit to adjust the bowden cable so you can get later shifts. A few degrees won't make a detectable difference. Throwing this info out there in case you adjusted it only a few degrees, instead of a few turns.
 

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Discussion Starter #9
What's the condition of the bowden cable? Is it adjusted taut, relaxed or tight?

If it is taut, it should shift normally through the gears.

If it is relaxed, it will shift very softly and early.

If it is tight, it will shift late and hard.

It is possible your cable is also adjusted too relaxed.

It takes quite a bit to adjust the bowden cable so you can get later shifts. A few degrees won't make a detectable difference. Throwing this info out there in case you adjusted it only a few degrees, instead of a few turns.
It was too slack when I first checked it a couple of weeks ago, so I adjusted it according to the FSM: disconnected the ball connector, adjusted it so that it lined up almost perfectly, with the slightest amount of stretch to reach the joint, then reattached.

Thanks,
Jim
 

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1983 300TD, 115,000 miles. Anthracite Gray
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Discussion Starter #10
P.S. At 4500 RPM, I'm doing about 37 mph. Hard to be too precise because my speedometer isn't perfectly calibrated and my GPS-based iPhone app has a response delay, which makes it hard to get a precise reading.
 

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1967 250 SL, 1965 300SE lang
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My 85 very clearly shifts 1 - 2 - 3 - 4 from a stop when I floor it. I sold some parts to a guy with a wagon and he said that he couldn't make it up his own driveway without a running start. I asked to drive his car and took it on an open road and it definitely had no first gear. This is probably irrelevant because my car has a later transmission than your car...
 

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Discussion Starter #12
Thanks Scoot. From what I understand, your transmission isn't THAT different from mine. Pretty sure mine ought to shift the same way.

The amazing thing is that, once you get used to the lack of power from stop, the car's still a pleasure to drive, even without first gear!

Jim
 

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It was too slack when I first checked it a couple of weeks ago, so I adjusted it according to the FSM: disconnected the ball connector, adjusted it so that it lined up almost perfectly, with the slightest amount of stretch to reach the joint, then reattached.

Thanks,
Jim
If you floor it from a standing start, how many shifts do you count?
 

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Discussion Starter #14
If you floor it from a standing start, how many shifts do you count?
Well, not having a proper track to stretch out on, it's not a perfect experiment. Not sure I've ever started from a standing start, floored it, and got up above, say, 65 before having to take the foot off the pedal. But so far I have never, ever, under any circumstances -- including floored -- counted more than 2 shifts.

Thanks,
Jim
 

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P.S. At 4500 RPM, I'm doing about 37 mph. Hard to be too precise because my speedometer isn't perfectly calibrated and my GPS-based iPhone app has a response delay, which makes it hard to get a precise reading.
37 mph at 4500 rpm isn't first gear, more like second gear.
 

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Well, not having a proper track to stretch out on, it's not a perfect experiment. Not sure I've ever started from a standing start, floored it, and got up above, say, 65 before having to take the foot off the pedal. But so far I have never, ever, under any circumstances -- including floored -- counted more than 2 shifts.

Thanks,
Jim
No need to get up to 65. You should be in top gear at around 40mph.

But if you accelerate hard enough you should feel the shifts. Weird that you do not count more than 2. How strong are the shifts?

For me, since we both have '83 models I do count 3 shifts from stop. This is without even flooring it, but I adjusted the cable enough to make it firm so this also somewhat gives me a bit more feedback as to what gear I am in.

And it's interesting that when you're creeping along you don't feel the downshift to first.

How about when you're at the stop light, or just stopped, in D. Then when you manually shift to L without releasing the brake, you should also feel it lock into first.

What's the condition of the shift linkage bushings? Is there any rattle or play in the shift lever?

I'm trying to rule out the easy to fix culprits.
 

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1967 250 SL, 1965 300SE lang
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I think he has no first gear.
 

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1983 300TD, 115,000 miles. Anthracite Gray
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Discussion Starter #18
How strong are the shifts?
Noticeable but smooth. FWIW, I did try adjusting the Bowden cable to make the shifts more firm. It made the shifts more firm, but there still were only two.

How about when you're at the stop light, or just stopped, in D. Then when you manually shift to L without releasing the brake, you should also feel it lock into first.
I don't think I've tried this; or rather, I haven't really paid attention. But I'm pretty sure I won't

What's the condition of the shift linkage bushings? Is there any rattle or play in the shift lever?
I haven't examined the bushings, but there's no rattle or play in the shift lever. This is a very clean car -- just 115,000 miles. Even the transmission seems very strong (except for the small matter of not having a first gear).

I'm trying to rule out the easy to fix culprits.
I appreciate that. The oddest thing in all this, IMO, is the fact that I had this car checked out two weeks ago by an Indie Mercedes specialist. And they said nothing about this. Very strange that they would have missed this. When I called them back, they tried to convince me that there was a first gear and that I was just missing it. I'm going to try to pay them a visit tomorrow.

Jim
 

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Well, if all of the easy tests show no sign of first gear, it's time to dig deeper and figure out if you have the correct transmission and if you do, figure out why first gear is non existent. Could be an internal problem as Scott posted earlier of another W123 w/o first gear.
 
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