Q: Metal fragments in Transmission fluid

asked by on February 28, 2017

6 months ago I had my transmission valve body replaced at the Mercedes dealership.. a few months after I felt the hard shift again while I was on a road trip. I didn't have the time to bring it in until this last week when it completely stopped shifting. The mechanic said that my transmission fluid was severely filled with metal fragments. They told me it would be around $8,500 when I started to question how this happened they told me that they don't have a crystal ball and can't tell when something like this would happen. They told me they replaced the transmission fluid when they changed the valve body.. wouldn't there have been signs of metal in the fluid then? I just want to know if this could be something they triggered when replacing the valve body 6 months ago. Yesterday they told me they would credit me $2,000 from the valve body replacement that I paid last time. Why would they credit me if it wasn't something they dropped the ball on. Please advise me.

My car has 115000 miles.
My car has an automatic transmission.

The reason they dropped the price by $2,000 (from $8,500) is because you can buy the entire transmission used (low miles, too) for about $1,000 to $2,000 using an on-line database such as Car-Part.com. Input your year, make and model at Car-Part.com and you will find lots of exact matches for your transmission. Of course, it’s risky buying a used transmission but if you are careful, or buy the transmission as a core and rebuild it yourself, you can save a lot of money. To install a used transmission in your car takes about 10 hours (roughly). To remove, re-build, and re-install your existing transmission would take at least 26 hours. No matter how you add up the numbers, $8,500 makes no sense. That is, if you obtain a good transmission core for $1,000 (i.e., a core with no broken hard parts, as you presently have), buy a re-build kit and miscellaneous parts for $1,000 and add 26 hours of labor at $80/hour, you’re up to $4,080. That’s why they’re willing to "drop" the price by $2,000, because the $2,000 cost component, insofar as the economics of the repair, does not, and never did, exist.


Changing the valve body will not precipitate a "hard parts" (gears, bearings, clutch components, etc.) failure in a transmission. As far as tell-tale signs of failure that might have existed during the first repair, there might have been but, as likely, the signs might have required a lab study of the fluid, and clutch "mud", to determine exactly what metals might have been present at possibly microscopic levels, or at least "small" enough to not be readily discernable as to source. Put simply, if a bearing (or gear) was on the verge of failing, they could have replaced the valve body without being able to detect that and thus the bearing failing is just really coincidental.


If you are interested in a transmission replacement or rebuild, YourMechanic professionals in certain locales can assist with that. Please simply inquire based on your locale. If you have further questions or concerns, do not hesitate to re-contact YourMechanic.

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