I just went thru this with an 03. PO gave it regular oil changes, I think, but nothing else.
I'd either use a real ATF+4 or amsoil. This is THE pedigree of transmissions that developed some of chrysler's worst reputation. And most of the failures came from using the wrong fluid (which the manual said was acceptable). you won't feel a difference, since the shifts are computer controlled, but the wrong fluid will cause excessive backing-off of the clutches, increasing wear.
I personally like the castrol ATF+4. It is, however, a little thinner than the others per the MSDS, so if it's worn, valvoline or another brand may be a better choice.
Also, the $11 filter sold by AAP is [censored]. It works fine, if you can get it to click-n-stick up there long enough to fit the pan. Spend more for a name-brand filter.
Also, rock auto - ATP JX160 inline filter is the rebadged magnefine that you can run inline with the cooler circuit. It's a much finer micron rating than the stock element, from what I've read.
I found I needed to do 1 drain fill + filter, and one other suction/drain & fill to get the fluid back to clean pink.
The 3.8 is one smooth engine in this vehicle. It's got a nice torque curve that just pulls that thing up long highway hills without shifting, without dropping lockup.... it's a wonderful motor. my VC gaskets were shot. They are pretty fancy--- $40 IIRC. you'll need 1/4" flex drive to get one bolt on each VC.
Also check all of the coolant hoses. mine were all very soft and were "ballooning" at operating temps rather than allowing the pressure to build. Gates belts were very reasonable online. The smaller heater lines, there are like 6 of them, I'm keeping an eye on.
The PS circuit says to use PS fluid but chrysler said later to use atf+4. I have a mix of atf+4 and what I had left of amsoil PS fluid in mine now. There is a 18" hose, pretty big, maybe 3/4" ID that goes from the pump to the tank over the rear VC... I pulled to change the gasket and quickly lost a good 1/2qt of PS fluid.
Also, check under the airbox. there are 2 small vac lines running front-rear with a service tap down there, and either a valve or pump under the rad support. that line is notorious for cracking and giving a P0442 and P0444 code. Mine was shot, and it looks like the PO installed new hoses everywhere else and charcoal canister with no success-- it was this 6" section of hose. Known for giving out.
It's an 06-- so it needs a coolant flush too. I found a shop vac on the rear heater lines pulled out another 1/2 gallon of water after running several cycles of tap water thru it all (refilled with distilled).
Note the condition of your sway bar link boots. mine are shot.
The rear plugs can be changed if you don't mind hugging the engine. (same dance with the rear VC). mine turned out to be pretty loose, scary but it made them easier to get out. I installed bosch plat +2s, not what I wanted but the best they had in stock, and it's running fine with them. Note-- it's a big gap-- like 0.050. These things WILL eat plug wires due to the high voltages needed to fire the plugs. Inspect your wires for burn marks.
I had an oil leak on the pan gasket. That was fairly easy to get off--- had to remove the flywheel cover since it blocks two of the pan bolts. Took my time and it was not a bad job.
Check your running voltage--- car on, fans on, brights on. measure voltage between alt frame and bat (-). should be well under 0.5 volt. If it's more, clean all grounds and/or add your own to tie batt-chassis-engine-computer. I had an 01 that had many problems until I found that. The 03 reads 0.1-2V with all of those loads on.
Inspect your brake fluid--- may be time to replace that as well.
we bought ours as a 3rd car for when we have all the kids at once (every other weekend). So ours has been a "project car" knowing it won't be a DD. These are very nice vehicles. also, there's a great forum.... the chrysler minivan fan club that is sort of like bitog. No-nonsense folks that just want to maintain them, keep them running, and don't put much creedance into loud stereos and performance intakes....
M
