Bad Advice??
 

I recently picked up an 87 190D Turbo with 200k. The previous owner seems to have taken good care of her, but he said something that rung hollow with me. He said NOT to change the ATF because it was a sure-fire way to kill a tranny. His reasoning was that the particles in the fluid enhanced the friction in the tranny, keeping it tight and strong. Fresh fluid would, he said, cause the tranny to slip.

This is crazy, right?

I don't agree with it. I believe a proper fluid and filter CHANGE can promote longevity and is no risk if done properly.

I understand many service sites are pushing powered fluid flushing/filtering. Call me old fashioned, but I don't believe in it.

There are corner cases in which the transmission clutches are so far worn that the uhh... crud suspended in the fluid keeps things moving. That can't possibly last for very long. If you're running the car into the ground then leave the transmission as is. If you're going to rely on this car for a while, service the transmission and bite the bullet in the unlikely chance it's so worn that it's hanging on by dirty fluid.

How does the fluid look now?

Sixto
87 300SDL

Perhaps someone with real firsthand knowledge and experience will chime in; however, if the pervious owner applied a significant # of the 200K miles w/o transmission service you may want to proceed with caution.

If I am not mistaken, some mechanics (including radio car talk host Pat Goss) recommend not changing the fluid in a neglected tranny unless it is discolored or burnt. I think this is based on the potential problem of seals and internal tranny components not functioning with new fluid because of the viscosity change.

Fluid Color
 

Thanks for the replies. So I'm looking for burnt smelling black fluid? If I find that then a change is a good idea, otherwise, better left alone?

Cheers

I say look at it in the drian pan after you've changed it. :) It needs serviced.

Len

Why consider for a nanosecond anything that conflicts with advice from the manufacturer? Life is too short to fill your head with needless questions.

no doubt in my mind
 

i would change it. drain and new filter. new pan gasket.

tom w

tranny killer
 

what kills your tranny is changing the fluid using one of these
reverse pumps..... it sucks the dirt back through the tranny and
does kill older trans..

go ahead and change it. its the powerflushers that cause
problems. do it the mb way and yer good to go.
have done hundreds and have not had one issue.

george

I'm with you on this one - how is a "powerflush" supposed to circulate fluid through the valve body without actually having the transmission in operation? How does it activate all the various valves to ensure the "flush" solvents get to all the places in the valve body that transmission fluid can go? It seems like a bunch of marketing BS to me.

power flush
 

power flush is the word i am looking for... never do it on
an old tranny....but change your tranny fluid any time you want.

well, it works by using pressure that will disturb stuff.
especially the stuff in the torque converter. yuk.
the only one i know thats worth using and is ok is
the one used by B.G.. there's is just a changer that uses
the trans pump as the force to exchange the fluid. it don't "flush"
but just exchanges fluid.

george

Call me a bit low tech but I guess I'd rather use gravity as the force to exchange the fluid.