It may have been a link that Jim posted that I have "quoted" a couple of times.
One reason for a OEM to not put a filter that filters down to a 30 micron particle size is maintenance interval.
One of the "selling" points of a new car is how much maintenance it "Requires" during its WARANTY period.
A filter that filters down to a smaller particle size will clog up sooner.
Add to that the engineered life of a vehicle.
The Magnefine is an external filter, very easy to change, as compared to the in pan filter.
It may have been the same information that was posted before that stated that, once a vehicle has been driven a few thousand miles, the BEST place to install the Magnefine filter is in the external transmission cooler line that has the fluid flowing INTO the transmission from the cooler.
HOWEVER, if you cannot find a good spot to mount it......either line is WAY better than not installing it at all.
Rule of thumb for the Magnefine is to replace once a year.
AzFireGuy mentions "bypass" filtration, also an external filter system.....YES, it is better than the magnefine, but more complex and expensive in the installation.
When a transmission fails, it can creat a lot of "crud" and contaminates, which can become lodged in the remote (in radiator) cooler.
This can restrict or even block the flow of transmission fluid through the cooler, causing the new transmission to overheat and fail.
Also, these contaminates can come free....and become lodged inside the transmission.....depending upon where they become lodged, they can also cause the new transmission to fail.
I know that FORD issued a couple of Technical Service Bulletins (TSBs) about this very issue and included instructions to dealerships on how to backflush the cooler using ONLY warm transmission fluid (no chemicals or additives) and how to verify that the cooler is not restricting the fluid flow.
FORD did this in response to repeated come backs with failed transmissions, and they found that it was greatly reduced by these 2 issues being addressed.
As for transmission repair?....it will depend upon what was wrong with the transmission in the first place, and what they did to repair it.
It sounds like they repaired the original transmission, which, given the mileage on the vehicle was likely a good thing.
Rebuilt transmissions (they swap your broken one for a rebuilt unit) can have been repaired to the standard of only doing the absolute minimum to get it going again, to replacement of all the normal wear items......and even incorporating OEM sanctioned inprovements to them.
The latter, is normally called "remanufacturing".
As one poster above mentioned, some shops install a Magnefine (sold under various names) or another brand name filter as a part of the repair process.
So, it is possible that you have one already.
They do this to reduce the likelyhood that you will be coming back with a problem.
As another poster mentioned, Chrysler 3 speeds were OK.....it is their 4 speeds that had issues.