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  #1  
Old 09-05-2004, 05:02 PM
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Arrow Newbie With an Oldie

Hi- just want to introduce myself to the Forum and tell ya what I just got! It is my first Mercedes- had to get it to satisfy my midlife crisis- and I promise not to do anything bad! So... I've just landed a white '76 300D, which I guess makes me a W115 with 617 engine guy, yes? The car really is surprisingly fabulous- it has 125,000 miles and was just driven 1200 miles to get it to me after purchasing off E-Bay. Other than a few minor rust spots on body panels, the body is perfect. Furthermore, everything works- AC, PW, PL, Cruise- even the little clock! I guess I should mention the Becker radio has been replaced.

But there is just one thing- the 4 speed automatic never seems to reach 4th. I have not gotten my plates and inspection yet so I personally only had it for a brief ride at 60 MPH, but it only got to 3rd gear. The guy who delivered the car for me observed how much the engine seemed to be revving at highway speed, and terrible fuel milage- I estimate from his fuel receipts he was only getting 25 mpg, yet he also said he was able to get the car up to 90 MPH at one point. I'm kinda thinking- if it never gets to 4th, it would never get to 90, would it? I have to wait until Tuesday to get my plates, then I'll take to the highway and push it beyond 60 to see what happens. Until then, I remain baffled- can anyone shed some light on this one?

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  #2  
Old 09-05-2004, 05:41 PM
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Do some research on transmission behavior. I suspect you have instantaneous 2-3/3-4 shifts so you feel overall 2 shifts rather than 3. Here's some reading on the topic - http://transmission.articles.mbz.org/

There's no way you'd reach 90mph or get 25mpg in 3rd. I think 25mpg is pretty darn good.

Sixto
95 S420
87 300SDL
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  #3  
Old 09-05-2004, 05:43 PM
tscott
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Wow, if it really and truely won't shift and you wind it up as high as you can that engine will really be turning. I had a 59 220 SE and often just forgot to shift to 4th at 60 mph.

I would definitely learn a little more about the car before testing it the way you've suggested.

I don't know anything about this specific car, but I have noticed that the words 'vacuum leak' appear in a surprising number of solutions.
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  #4  
Old 09-05-2004, 05:59 PM
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Welcome to the forum. It might be helpful to note what RPM you have at say 60 mph and then compare notes here. That should give you an answer.

25 mpg I believe is not that far off from what you might expect!

Steve...................
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  #5  
Old 09-05-2004, 06:13 PM
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Post No Tach

Quote:
Originally Posted by sarafin
Welcome to the forum. It might be helpful to note what RPM you have at say 60 mph and then compare notes here. That should give you an answer.

25 mpg I believe is not that far off from what you might expect!

Steve...................
Car doesn't have Tachometer

Dave
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  #6  
Old 09-05-2004, 06:28 PM
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Quote:
Originally Posted by coldwar
Car doesn't have Tachometer

Dave

Hmmm, I assumed all MB diesels had tachs! Of the three MB's I've owned, all made in the 80's, all had tachs.

I have noticed since owning my Benz's that all three reved higher by as much as 300 to 400 rpm at highway speeds than other kinds of cars I have owned!
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  #7  
Old 09-05-2004, 08:17 PM
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My '84 300SD hits 70 mph at right around 3000 rpm.

If you can find a way to measure your rpm, maybe this will help.

Mine is going through all four gears.

Welcome to the board and Mercedes ownership!
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  #8  
Old 09-05-2004, 09:31 PM
mb123mercedes
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Also most diesels take off in 2nd gear.

So you might be thinking 3rd while it actually is
in 4th.

Louis.
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  #9  
Old 09-05-2004, 09:35 PM
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I was of the opinion that MB Diesels didn't start in second gear. The SDL and both my SDs (81, 83) start in first.

Sixto
95 S420
87 300SDL
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  #10  
Old 09-05-2004, 09:47 PM
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My daughter's 78 240D usually takes off in 2nd unless you push it to the floor to activate the kickdown switch. She has it down pack and can take off and keep with traffic even though it's an automatic. BTW, it has no tach.
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  #11  
Old 09-05-2004, 10:37 PM
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My 77 300d is definitely designed to start in 2nd. Later 123's started in 1st. (my 85 300td does). On the earlier models, if you put the gearshift in L and then move back to D (before moving), it will start in 1st and shift all the way up thru the gears. It will also start in 1st if you push down hard enough to engage the kickdown switch.
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  #12  
Old 09-05-2004, 10:42 PM
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Hey Coldwar,

I just got my '79 300D last weekend and thought the same thing. I drove 4 1/2 hrs to the Chicago area to get it and drove it back. The whole way I'm thinking, wow, this motor seems to be reving high for 65 mph. No tach in the '79's either. Well, I was messing around with the gears and noticed that when I put it in Low or 1st, it was in a lower gear than what it starts out in. Based on that I assume I'm reaching fourth when it has only shifted twice from a stop. These things must start out in second, because the Low or 1st is [B]really low. I put new tires in it and it runs/sounds better at higher speeds, but still seems too loud at 65. Maybe that's just the way a '70's benz is supposed to sound - but I have read some people on Ebay saying these things will run down the interstate at 80 mph all day - definately not this one. I wouldn't want to run it up to 80 right now. I'm thinking maybe something with the driveshaft or related. It's going in the shop next week for a checkover.
Try putting yours in low and see if it is lower than what you start out in. Let me know if you figure anything out!
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  #13  
Old 09-05-2004, 10:53 PM
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KerryEdwards, (it hurt to type that)

How does your 300D sound at 65 - 70mph??
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  #14  
Old 09-06-2004, 10:09 AM
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My 300d sounds pretty quite and smooth at that speed. However, the sound of the motors is all relative. I have a 409d van with the 617. It's top speed is around 68mph. So, at 65, that motor is turning MUCH faster than the same engine in the 300d (no tach but i'd guess a miniumum of 1500rpm's faster) so relatively speaking, the 300d rpm's are slow.
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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
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  #15  
Old 09-06-2004, 10:30 AM
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Got It!

Quote:
Originally Posted by kerry edwards
On the earlier models, if you put the gearshift in L and then move back to D (before moving), it will start in 1st and shift all the way up thru the gears.
Right on Kerry- I tried it and that's exactly what mine does. If I pull the stick to "D" then to "L", with my foot on the brake I feel a gentle thunk, then the car takes off through all 4 gears. What a relief!!! The tranny is very refined too- no harsh shifting- just enough to feel which to me is just right.

Thanks everyone for your answers to this puzzle, and I'm so relieved I don't have to get into a situation with the eBay seller over this.

Dave

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