Time to change the tranny fluid in the Caravan. It uses ATF+3, the "older" fluid. Chrysler and the oil companies quit manufacturing it in the past year. Not so good. Even though they say the newer ATF+4 is backward-compatible, people have had problems when using it on pre-2000 Caravan transmissions. (Technical Service Bulletins 21-006-01 and 21-004-04 specify ATF+4 is for use in 2000 and later models). Reports indicate that the newer fluid degrades the seals in the pre-2000 transmissions.

Not much incentive to changing the fluid when it can only make things worse... Maybe it's better to leave the old stuff in there.

It got me to thinking, though. What do we do, those of us with pre-2000 Chryslers, to prevent ruining the notoriously delicate transmissions?

CRAZY IDEA #1 - Re-use the old fluid: filter it through an old T-shirt to remove particulate matter.

CRAZY IDEA #2 - Search for a chemical breakdown of both ATF+3 and ATF+4. Find out what's different and try to get additive(s) to make the "4" more like the "3". Keeping in mind that the problem is with seal-degradation, prospective additives would be among those touting "Seal-Conditioning" properties (but be cautious about anything that might alter the viscosity).

"ARE YOU NUTS? Suggesting additives for the ultra-sensitive Chrysler transaxles?" Maybe. But if we're left in the lurch with no safe Tranny Fluid, all I can do is examine some alternatives. But I'm not quite ready to pour any mystery fluid into the spout just yet. But I'll be digging around for an answer. SOMEBODY out there knows: Chrysler tranny designers, chemists, mad scientists... The answer exists somewhere; if I find it I'll let you know.