Sometimes it seems like it never ends. 83 240D manual tranny w/ 84 300SD engine. Just replaced the clutch master cylinder and slave cylinder. A few times before the new master/slave the car would pop out of first gear under low load conditions. Now it pops out of first about 30% of the time. Also, starting around the same time, I would hear a much more high pitched whine than normal in 3rd gear only. What do these indications mean? I really hope it doesn't mean I need a new transmission.

I wonder if you have an alignment issue between engine and tranny or maybe a bad pilot bearing.

You have bad bearings in the tranny.

The whine is going to get progressively worse and then it will be hard to get the car in certain gears. There are support bearing that hold up each end of the internal shafts, they wear and start to whine. You can just rebuild the tranny and bearings while you are in there.

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
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Is there such a thing as a manual transmission rebuild kit? If so, where would I get such a thing? Thinking about tracking down another 4 speed manual to rebuild so I don't have to lose too much time without the car. Any info would be appreciated.

Sure you can get a rebuild kit!

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair

Rebuild it now, while you may get away with seals and bearings. You really don't want to buy many shafts or gears for a manual transmission, regardless of brand.

Where do you recommend getting MB manual transmission rebuild kits?

Ken300D

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1982 300D at 351K miles
1984 300SD at 217K miles
1987 300D at 370K miles

Do not let it intiminate you if you are going to do it. Usually pretty simple with the older boxes. Last one I did was a five ton truck and the transmission was a little heavier. Replaced syncro ring and second gear. Was very quick. For expediency if you can locate another transmission it might be the way to go. Time waiting for parts when you establish what you need might take a few days. Think there is even a description in the haynes manual of the teardown and rebuild process. Usually not required as it is so straightforward. If you just require a new bearing or bearings they might be obtainable from a local bearing house if you have one in your area. That way you could have it out, bearing or bearings replaced, and back in the same day. My main point is it is generally a pretty easy thing to do if you decide to tackle it. Where you running with low transmission fluid? These boxes are supposedly pretty rugged but everything fails eventually.

From my knowledge of the same transmission issue on the Saab, I'd say the whine is coming from the worn-out pinion bearing. That indeed means time to rebuild. If it's popping out of gear, I'd guess it means that the condition of the tranny is already pretty bad and you should definitely plan on doing it soon. In Saab 900, if you wait too long, the tranny may lock up and at that point will not even be rebuildable (so you'd have to spend more money getting a fresh rebuilt tranny from places like Ericsson), but I guess it could be different on Mercedes - no idea there.

Gear whine is worn bearings.....poping out of gear is a septerate issue...worn gear faces and syncronisers. Might be easier to source a good used transmission. If the whine is noticible to you then its been doing it a long time adn your gears have worn funny. I went through that 20 years ago with my Jeep...by the time I noticed the whine was unusual the gears were already toast.

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Proud owner of ....
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Unlike on the Saab, the Mercedes pinion bearing is in the rear.

Worn bearings can indeed cause popping out of gear, but when that happens it usually causes excessive wear on the engagement teeth. It does sound like you'll need a few hard parts, but it's impossible to be sure without tearing it down.

a used 4 sp manual w/ 60,000 miles on it for $250. I think the only difference between mine and the new one is my reverse lever is in a different configuration. The reverse lever linkage is still attached to the newer tranny, so a little minor adjustment and all things should be good, right? What other things should I look at while I'm swapping out trannys? Thanks again!

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Frau Frankenbenz: 1983 240D manual w/ 1984 300SD engine; 81 240D tranny; 2.88 diff. 317,XXX miles.

2004 VW Passat TDI Wagon: Offline awaiting an oil pump balance shaft delete

1978 International Scout 4 Cyl all stock: Awaiting exhaust repair

2005 Ford E350 Diesel: Getting everything from point A to B without complaint

Thats seems like a good price.

I think if the reverse shift arm is streight up, its an early tranny, the shafts coming out are splined. Anyway I think you will need to use the shift rods that came with the new tranny or shorten the old rev. rod. (which is what I did)You wont have any problem

If you can get the old throw out bearing, compair it carfully with yours. There are two different bearings for these trannys. Its no fun to pull the tranny again to change them, I know

The last wrecking yd tranny I got had 90w in it when i opened it up

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

I'll have to check and see if the throwout bearing is still there. If not, do you think if I enter in a 76 240D in a parts search that I should find the right throwout bearing? Also, are there any other things to look at while I'm doing the swap? (sorry to repeat myself, but I don't want to have to yank and install this thing more times than I have to.) Thanks!

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Frau Frankenbenz: 1983 240D manual w/ 1984 300SD engine; 81 240D tranny; 2.88 diff. 317,XXX miles.

2004 VW Passat TDI Wagon: Offline awaiting an oil pump balance shaft delete

1978 International Scout 4 Cyl all stock: Awaiting exhaust repair

2005 Ford E350 Diesel: Getting everything from point A to B without complaint

you getting a tranny from a 76?

have you checked to be sure it will bolt up? there are some years in there that dont co-oincide but i can't remember which ones. i am not saying you have a problem, but just to be sure.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.