ATF fluid type mixing ok? C280
 

Hi,
Quick question. I replaced a broken ATF hose going to my radiator. I lossed a lot of fluid when the hose broke and I noticed that after I filled it back up with Dextron III type, I inadvertently poured in 1 quart of Type F (Ford) fluid. Will this hurt my transmission?

Thanks for the advice!

-Andrew

Best be safe and not sorry. Its easy to drain and re-fill.

Hi
What year is the C280? If it has the 722.6 transmission (W S switch on shifter), then you really need to get the fluid out. There is a special fluid sold by MB that is the only one recommended for that trans.
I would think the type F would be similar to DexronIII/Mercon. Unsure if 1 quart of it will bother or not.
Gilly

Its a '95 C280 (75K miles). A friend of mine (not a MB tech) said that basically the type F is a slightly different viscosity than the Dextron and said one quart probably wont hurt anything. I just don't like the work probably so I think I might be safe and just drain it and refill.

The real difference between Type F and Dexron:
 

Type F lacks certain "friction modifier" additives which were necessary for cars which specified Type A in the old days (superceded by the various Dexron/Mercon things) to shift smoothly. If you put Dexron in a transmission which needs Type F it will shift VERY smoothly, but burn out its clutches rather rapidly -- this is a very common problem nowadays for owners of classic SAAB 900 models and other older European cars with Borg-Warner type 35 and 37 transmissions: people substitute Dexron, thinking it's just an improvement, and shorten the life of their transmissions rather drastically. If, on the other hand, you put a large amount of Type F in a transmission intended for Type A or Dexron, as drag racers used to do all the time in the '60s, you just get much firmer shifting. I suspect that some of the cheaper "shift improvers" or "transmission performance improvers" in auto parts stores are just repackaged Type F.

I believe that the major factor in the change from Type A to Dexron designation was the invention of a synthetic friction modifier additive: Type A used genuine whale oil, and the limits on whale hunting made it difficult to obtain enough for all those GM cars.

tranny Fluid Mixing is no-no
 

Drain and refill be sure and drain the torque convertor too.

Type F is very corrosive to copper and has different friction characteristics (coefficient of dynamic friction is much higher than Dexron--which will give firmer shifts--and potentially overload clutch packs during clutch engagement.)