Project Chronicle

The replacement transmission is in the 500E, and I was able to put some miles on the car this weekend. The good news is, we've resolved the biggest issues the car had, which was a near non-existent reverse gear and very lazy forward shifting. One thing that stands out right away is how urgently this car upshifts. I've read it's adaptive, meaning you need to manually shift it to set the preferred shift points; I've also read that the Bowden cable can sometimes need adjustment. Regardless, it drives down the road nicely, but the lack of rapid downshifting requires further investigation. 

I had a sneaking suspicion when the 500E arrived that I was due for transmission trouble. The seller was an honest guy, but it seemed he was in the camp of being able to live with some flaws that I wouldn't be able to abide.

The 722.365 automatic transmission found in the 500E is used across the W124 lineup. It's a fairly reliable transmission but does have a certain life expectancy. The tell-tale sign is longer and longer engagement to go into reverse. Two seconds is normal; anything longer is considered indicative of the gearbox being on its way out. My delay was about 4 seconds. 

We did a bunch of work hoping to remove any doubt about the transmission. The transmission bushings and differential "guibos" were all replaced to tighten up the gearbox action. While the shifter moved more confidently through the gate, it did nothing to address the delay going into reverse. 

No dice. So, after weighing a transmission rebuild, we bit the bullet and ordered a rebuilt transmission from Sun Valley, a known rebuilder of Mercedes gearboxes. It's on order and will be installed in the coming weeks. While unfortunate, it will be a major value add to the 500E's future price tag.

The progress on the 500E has been slow, but I'm not terribly worried; there's been no ugly discoveries at the moment, and it seems like my fears about transmission issues are unfounded. Most of the issues with regards to slow shifting and noises in reverse have nothing to do with the transmission itself but rather heavily worn rubber components that help to support the transmission and driveshaft. 

Knowing that the transmission itself is likely fine is a major win. In addition to the shifter bushings, the transmission mount itself is very tired; both "guibos" on the driveshaft are heavily cracked and overdue for replacement; the noise heard in reverse was actually an insulation pad that was dropping down and rubbing on the driveshaft; ball joints, steering linkage, and the lower control arm bushings, all shot; and the shop also discovered a long-festering fuel leak coming from the charcoal canister in the driver's side wheel well. 

Right now, the exhaust and the driveshaft are dropped in preparation for repairing all that I just mentioned. Once we're through that, we'll see how much the drive quality has improved and what may need to be done next.

My 1992 500E arrived this week, and I have some thoughts. First, I bought this car on the basis of the honesty of the presentation and the seller. The seller, who I believe is a legitimate rocket scientist, had clearly been proactive on some big items, and the 500E had been passed between him and his brother since 2003. 

I feel a paid a very fair price, and with that, comes the expectation that there will be some issues. The bigger and better news is, however, is that the cosmetics were better than expected; the interior smells good; the portfolio of records that accompanied the car are solid; and there's lots of OEM parts, from the glass to the body panels, still affixed. The widebody fenders are much more impressive in person and the car has a great stance. The disclosure about the faded paint was accurate, but the car still looks better than expected. 

The issues seem to stem solely from lack of use. The suspension feels a bit tired. The shifter bushings are non-existent, and make it difficult when cold for the shift selector to move between gears. There's a whine in reverse that has me nervous - these cars are known to need rebuilds of the various clutches in the gearbox - but we'll do the shift bushings first before I start shopping for rebuilt transmission. I don't have records of any major cooling system work, so I'll likely proactively replace the water pump and thermostat. The other major disclosed flaw is an errant battery drain that could be traced back to a replaced under-dash wiring harness, but for now, the seller removed the number 9 fuse which controls things like the flashers to ensure it doesn't drain the battery while it sits.

Overall, a pretty manageable lists aside from some cosmetic repairs, and when complete, I feel confident we'll have a car worth more than the cost of the repairs and purchase price.