Calling all techs and engineers!
Since the time is drawing near when I again must change my transmission fluid, and having seen a synthetic version on the shelves recently, I've been wondering if it's worth the switch. I don't think there's much of a cost vs. benefit issue here, even though the synthetic stuff is 2-3x the price of the mineral version, since the ultimate retail price is still a pittance for a service performed once every year or two. Rather, is there a technical benefit to be had for the typical driver? Is there a downside to switching to synthetic after thousands of kilometers of using the standard stuff?
Appreciate any and all comments.
Regards,
Nick

I have always thought that if you stayed with what you are already using and not having problems with, why change??

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Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM

Downside, like switching to synthetic oil, is if your car's not new(er) then you may spring leaks becasue of the improved flow and different characteristics of synthetic. However, I am confident that synthetic fluids decrease wear and flow dramatically better at low temps. I run Red Line Syn fluid in both of my trannys, and was lucky enough not to spring any leaks. It's all I run.

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Best regards, Michael
'92 500E
'88 300TE

Hi Michael,
At what mileage did you switch your cars over? My 86 is approaching 200k kilometers, the 89 is at around 250k.
Thanks,
Nick

I converted my 300TE at 67k miles in 1997. The 500E was converted at 43k miles in 1999.

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Best regards, Michael
'92 500E
'88 300TE

As with engine oil, I only trust Castrol products. I use Castrol Dexron III/Mercon in all of my cars and it works just fine. If you are changing your own tranny filter and fluid, make absolutely sure that the cork gaskets come off when you remove the filter or else you're looking for trouble. After you have the new filter installed and the pan back on, fill with four quarts then start the car and let it warm to normal operating temp. You can then begin to add fluid to specified level. One more hint, after you have topped the fluid up, put the car in reverse for about 30 seconds or so, this will clean out the valve body. You can then cycle it through the rest of the gears then re-check the fluid level. Hope this helps!

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Rgds,
Aaron Greenberg
MB technician
Precision Motorcars, Cincinnati, Ohio
'67 250SE Cabriolet
'77 450SL
'79 6.9
'80 300SD
'85 380SE
'89 420SEL
'93 300E 2.8