I checked in this site a year or so ago, and got some great advice on changing my timing belt which went successfully well. Now, am having an occuring problem with the trans. I have been searching the archived threads, and learning a bit, but want to ask a bit more.
I have been experiencing a bit of hesitation ( i thought) over the last month or so. Checked the plugs, trouble codes, etc. and nothing to be concerned with, but along the way realized that the hesitation occured during open road driving. Just a slight drag for a few seconds, and then fine again. Then i noticed the tach elevating during the 'drag' and have had the trans slip into a lower gear several times. Noticing the tach response led me to understand that it was slipping into a lower gear (D to 3) and once as i was stopping at a light, it shifted from whatever gear it was in, to the next lower quickly. I didn't manually shift it back up, it just shifted back on its own.
Now, i've read dozens of threads on the 91 trans: the filters- internal and external- and changing them and still don't know what is causing the problems. Is it a dirty filter? One filter is supposed to be lifetime, the other is recommended replacement, but i'm not sure which needs what. The internal i've read here can be cleaned, but the auto parts stores here (NC,US) only sell the internal. The external ones (added on, for the trans cooler) should be replaced ? but no parts store knows what i'm talking about with it, and my Haynes manual shows the lines for the cooler into the radiator, but not the filter that is in that line. Again, i understand the filter was added due to recall, but does it need replacing?
And, again, what is causing the problem? I've changed the trans fluid but it didn't change the slipping down. I understand that the simple draining/adding 4 qts is not changing all of the fluid, and perhaps the flushing/replacement of complete fluid is needed and will seek that next week. I'm just wondering if someone has found this to be the actual remedy, or does this problem actually exist further than a fluid change remedies? I've read not to have the band adjusted, and don't want to just turn this over to a trans mechanic for work that's not needed.
At this point in time i have my time and resources (read $$) tied up in another vehicle that i get more than enough crap (read smartass answers from another group dealing with that engine) and as this is my daily driver and the other is a recreational vehicle only (okay, it's a vw camper) i'd appreciate any serious reply. Just want to know if the filter/filters/complete fluid change remedy the problem, or does something more serious underlie it all .
thanks in advance for your help. dp