dlarrivee said:
I already agreed that it would be best to stick with Dexron III, because it was closest to what would have come in the tranny from the factory. However, I still don't think that ATF+4 would destroy an AW4. Oh, and I'm not to concerned with who thinks they're "senior" to me, their opinion is still just an opinion, unless it's backed up. If you read the whole thread you'd see that two people are using ATF+4 without problems.
1. Just for fun see what Chrysler has to say about using Dexron in there transmissions.
2: If your really interested, do some testing on your own, a few simple tests can tell a story. Friction properties, viscosity, adhesion etc.
3. I know for a fact Chrysler (and/or New Process) has screwed up the fluid recommendations on various trannies and gear boxes, over the years.
4. Compare the price of Dexron and AFT 4, things could be different in the states, but the price here is more than double for ATF 4.
5. If it ain't broke don't fix it, the tranny was designed to work with Dexron, which was fast becoming the standard when the tranny was designed. Then they even started messing with that formula (Dexron II, III etc.), I seriously doubt they modified it to make it better, more likely modified it to make it cheaper. A letter I read at the time, said in effect Dexron (I) was overrefined and over filtered (too pure, unnecessarily so).
6. Should have kept the letter I once saw, shortly after Chrysler took over Jeep. The object of the whole ATF 3 and 4 controversy was to reduce redundant stocks at the service centers. Not what was best, or even better. Another reason stated in the letter was to avoid Chrysler mechanics from inadvertently using Dexron in Chryco trannies, back to number one.
Just an observation, the newer Dexrons seem more heat sensitive than the older ones were, if nothing else the color changes at lower temperatures or more easily.
Twice now in two different vehicles, a Chrysler service center changed out my tranny fluid and added ATF 3 ( I believe) actually just a half change and both times the clutches were noticeably slipperier, I might have left the fluid in there until the clutches died, but decided to do multiple drain and refills back to Dexron. Once was seven years ago and the other about 5, both trannies are doing well. Original AW4's one twenty years old the other 19 years old.
Tranny fluids are a compromise, between a hydraulic fluid, a lubricant and wet clutch friction agent. The friction design properties, the pressures and the designed slippage in the clutches is rather critical for longevity.
IMO
