300D tranny slip

[seth]

The car is a '75 300D. I bought it not running and drove it for the first time today. It seemed to be running great. No smoke, sounded good (considering the holes in the exhaust). After driving it around town a little I went up a hill and the engine was reving but I didn't get any acceleration. I thought it just wasn't going into gear for some reason. At the top of the hill it cought. Shortly after, when accelerating from a stop it did the same thing. This time I could hear a squeaking and it smelled pretty hot. I'm affraid the transmission is toast. I've never owned an automatic before so I don't know much about them. Any help would be great.

[Tomguy]

You say you bought it not running - before taking it out the first time, did you change the tranny fluid? Drain the ATF (including the torque converter), replace the filter and gasket, and renew it with clean fresh fluid. It really sounds like it's low on fluid which probably would have burned what was in it.

[seth]

I was going to try the fluids. I didn't know there was touque converter fluid... thanks.

[Tristar1959]

Most of those trannies' torque convertors have a drain which is accessible when you line it up with the hole in the bottom screen - using an allen wrench to open the plug.
The reason to drain the TC is because it contains a large proportion of the fluid - if you're draining just the pan and refilling, you're diluting or titrating the old with new, but not really replacing it...
Since it's unlikely you'll be able to "bump" the motor into exactly that right position, you may need to get a 27mm socket (check me on that, you diesel guys) into your crank pulley, to turn with precision.

A filter/gasket set shouldn't set you back much, or perhaps two - one for the continued flushing and the second after you get things settled down and running right. Check for your transmission number along the lower R edge of the bottom casting, something like a "722.xx" number and serial - there are at least two different pan/filter depths, and you want to get the correct one. Some versions also do not have a pan drain plug - those you have to drain by loosening the filler tube. Don't give up right away, sometimes these buggers DO "heal", following a transfusion. By the way, since you probably can't find the owner's manual's "Type A" ATF anymore, use a Dexron.

When refilling, you don't want to OVERfill it, either - you'll put in a couple of quarts, run briefly and cycle through D & R a couple of times, recheck dipstick, and add until you are between the marks. The fluid should be at the lower mark when cold, the upper when hot.

IF you need odds and ends of data to do this, let the guys know what your year/VIN are...that helps a lot.

If it turns out to be toast, and you like manuals, and the car's a keeper - lots of guys have converted 300D's using 240D clutch/manual tranny pieces-parts. Threads exist, and lots of us can put you in touch with guys who have done it.

Good luck with the auto, for now...

Stan

[seth]

Thanks! Believe it or not I have all the original owner's manuals with the factory maintenance log. It was very well maintaned up until what looks like the second owner sold it 15 years ago.

[Tristar1959]

Seth,

According to my 114-115 Service Manual, your '75 300D should be a 115.114 model (that's a W115 chassis, variant # 114). Your VIN should be 115.114 12 xxxxxx.
If that's the case, your car at least started life with a W 4 B 025 transmission.
The "refilling" capacity is listed as 6.1 litres, "oil change" as 4.8 litres, in your 115.114, as well as 114.115's , 114.015; and 115.015, 017, 110, and .117's.

[NOTE for other W 4 B 025 users -

For 107.022 and .042; 114.011, 023, 060, 062, 072 and 073; 116.020, 024 and 025; 6.6 litres "refilling" and 5.3 litres "oil change"]

SERVICING REFILL
Quote:

"First, fill a major quantity of oil, (approx. 4 lits.) of an approved automatic transmission fluid through a funnel with a fine-meshed strainer [at that time, many Euro and still Asian garages filled from bulk barrels] into tube for oil dipstick with the engine stopped [Duh!]. Start engine in selector lever position "P" and run at idling speed. Add remaining oil immediately"

"Operate service brake and leave selector lever in each position for a few seconds. Then check oil level (refer to Job No. 27.3-010)" [Ignore, for the moment]
"Attention The oil level in the transmission will change with the oil temperature. The markings (max. and min.) on oil dipstick refer to an oil temperature of 80 deg C [176 deg F] - normal operating temperature of transmission during operation. However, at an oil temperature of 20-30 deg C [68-86 deg F] the max. oil level of transmission K 4 C 025 is at minimum mark, and that of transmission W 4 B 025 [yours] is 30 mm [1.18 inches] below minimum mark on a dipstick
These data serve for orientation during an oil change, which is generally made at this oil temperature."

NORMAL CHECK:

"The checkup is made with the engine running, the parking brake pulled and the selector lever in position "P", with the vehicle resting on level ground in unloaded condition" [I also recommend that the driver be in unloaded condition]

"Prior to the checkup, run engine for approx. 1-2 minutes at idle speed, so that the torque converter/hydraulic clutch can fill up"

"The oil level checkup can be made with the transmission cold or warm. However, the oil level can be determined more accurately when the transmission is cold (20 to 30 deg ATF temperature), than when the transmission is warm (80 deg C ATF temperature). The ATF temperature of 80 deg C is attained only after driving for some time and can only be estimated even then."

"Measure oil level with the oil dipstick completely immersed. When using dipstick with snap lock, with snap lever opened."

"Absolute cleanliness is essential. Wipe oil dipstick with a lintfree cloth (leather is best). Even insignificant contamination may result in operating trouble."

[Repeats section adressing the markings, esp the 30mm below the MINIMUM mark, at 68-86F]

NOW, THE CAUTIONARY NOTES:

"If the oil level is too low, the oil pump will suck up air, which can be clearly heard, The oil will foam and provide wrong results, when checking now. Wait until the oil foam is down (for approx. 2 minutes), add oil and check oil level.

Excessive transmission fluid must be drained or drawn off, since otherwise the transmission gears will be splashing in oil. The temperature will increase until the foaming oil is ejected through breather.

Continuous operation under such circumstances will lead to transmission damage. The syringe for rinsing the oil cooler can be provided with a hose and can then be used for drawing off excess transmission fluid.

Then actuate service brake when the upper dipstick mark is attained after adding oil. Leave selector lever in position R-N-D-N-R- in each position for several seconds - and move back to position "P", so that the working pistons of the servo members are charged with oil. Then check oil level once again and make corrections, if required"

WOW - those Huns sure could write detailed instructions!


Gotta admit, didn't know that about the different readings of the tranny types and capacity variations of same tranny in different cars.

Oh, and when you change filter, the oil pan bolts torque is 7 Nm.

Stan