Manual transmission grinds going into 2nd gear

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Manual transmission grinds going into 2nd gear

The manufacturer recommends ATF for the lubricant. Drain the ATF and replace it with 75W90 synthetic gear lube and add some molybdinum disulfide. After doing that mine doesn't grind any more unless I wind it up and shift aggressively. If it's still crunchy then there is an inexpensive syncro ring that will correct this. The Haynes repair manual has nicely detailed exploded drawings that match those from Mercedes perfectly. And step by step 1 2 3 instructions. 2nd gear syncro ring wears out first especially in an around town car, more so if its been down shifted which puts lots of wear on the syncro mechanism. Down shifting uses the momentum of the vehicle to force two shafts in the transmission to spin much faster... against friction forces. Upshifting uses the momentum to force them so spin slower which is low stress on the same synchro ring... with the help of friction in the bearings. You don't need to pay 2K or more for a rebuilt transmission and labor to install it .... but you do have to replace this ring or get someone else to do it. The ring is only $40. Replace any noisy or rough bearings while you are at it and you'll be back in business for another 200 to 300 thousand miles. These transmissions are built like Fort Knox, they have needle bearings on gears where American trannys are "bushed" , ie they have bushings instead. "Bushed" is a term appropriate enough for a cheesy low grade approach.


Nobody in the SF Bay area I can find is working on them any more but there are a few German old timers who know about them and will chit chat about them.