|
Hi Eric,
Aside from the IPD warning (more on that in a minute) "old school" knowledge argues that replacing very dirty fluid in a long negelected automatic transmission can be problematic.
The basic problem is that clean transmission fluid functions as a solvent, and it can dislodge gunk that has collected over many years. This can negatively affect the operation of the transmission.
I experienced a somewhat analogous situation about two years ago. My '87 240 has over 300,000 miles and has had regular trans fluid changes over its life. However the dealer who did the change this time uses an aftermaket trans additive along with the new fluid (I didn't know this at the time). I don't know quite what it was (most of these contain a detergent, plus friction modifiers, etc) but within a week my car had a much harder 3-2 downshift--now it really slammed into the lower gear. I immediately flushed the tranny again myself, but the situation remained the same. This didn't end up being any more than an annoyance, but it's a good illustration of what disturbing the tranny "status quo" can do.
I wouldn't worry *too* much about the IPD note--sounds like an extreme situation. However if it makes you feel better you could save the old fluid until you see how the car runs with the new--if the gunk in the old fluid makes the tranny operate correctly, presumably re-replacing the fluid with the original stuff would put you back to square 1. This is easy to do--just drain the old fluid into gallon plastic milk jugs so you have it if needed.
The bigger problem, as I see it, is the solvent effect of new fluid. There is no way to reverse any changes that might occur.
Not sure what to advise--good reasons to go either way. Bummer though. You want to improve your car but trying to do so could potentially make it worse.
HTH,
Dschwied
|
