Next transmission service?

The factory service manual for the various Grand Marquis' I've owned states that changing the filter is not necessary during routine fluid changes.

The purpose of the filter is to capture any debris left over from manufacturing and from initial break-in. If you're doing timely fluid services there's no need to replace the filter after the initial change.

There are also threads on here showing that Honda states the same about their filters.

I tend to agree with this outlook.

Show me an otherwise healthy transmission that failed because of a dirty/clogged filter. If a trans filter is plugged up from clutch material or wear metals, it was on its way out anyways. The filter in the Ford 10R80/60, for example, is robust enough that I really do believe it'll last the life of the trans unit. To my knowledge, Ford does not recommend replacing the filter on those transmissions even during the fluid exchange process.
 
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The cleanliness of the magnet and pan are of utmost importance. Most transmission filters I've seen are not capable of capturing enough of the wear material.

I always recommend dropping the pan for an annual cleaning until you've established a pattern.
 
Say what? Can you elaborate more on this?

All of this depends on the application, but in general:

The magnet is actively filtering the fluid of the most harmful particles (steel) 24hrs a day. As the magnet loads up it looses effectiveness. Keeping the magnet clean, and adding magnets (which many MFGs have been doing) improves the cleanliness of the fluid and reduces wear... which helps keep the fluid clean. Keeping the fluid clean helps keep it clean.

The pan will also act as a filter due to gravity and polar attraction. You might notice a dark film on metal surfaces in the transmission (aluminum, steel), ideally you want those particles out of the transmission and not in the fluid. Keeping the pan clean will help.
 
All of this depends on the application, but in general:

The magnet is actively filtering the fluid of the most harmful particles (steel) 24hrs a day. As the magnet loads up it looses effectiveness. Keeping the magnet clean, and adding magnets (which many MFGs have been doing) improves the cleanliness of the fluid and reduces wear... which helps keep the fluid clean. Keeping the fluid clean helps keep it clean.

The pan will also act as a filter due to gravity and polar attraction. You might notice a dark film on metal surfaces in the transmission (aluminum, steel), ideally you want those particles out of the transmission and not in the fluid. Keeping the pan clean will help.
I find if doing that first cleaning at 20k - new filter and adding a drain plug - I can get to 60k by just dumping a pan volume here and there -
Normally the magnets were worse at 20k (break in metal) than with twice the miles (20-60) …
 
All of this depends on the application, but in general:

The magnet is actively filtering the fluid of the most harmful particles (steel) 24hrs a day. As the magnet loads up it looses effectiveness. Keeping the magnet clean, and adding magnets (which many MFGs have been doing) improves the cleanliness of the fluid and reduces wear... which helps keep the fluid clean. Keeping the fluid clean helps keep it clean.

The pan will also act as a filter due to gravity and polar attraction. You might notice a dark film on metal surfaces in the transmission (aluminum, steel), ideally you want those particles out of the transmission and not in the fluid. Keeping the pan clean will help.
This mostly happens during break in. That’s why I’m a proponent of dropping the pan early in the first 20k miles or so.

After that, the magnet will be good for a long, long time like 100k miles. No need to drop the pan just to clean the magnets. Regular fluid changes will be more than enough to keep the fluid clean.

As far as the pan goes, the particles are simply too small to stay at the bottom, they will always be picked up by the fluid. And if you have chunks big enough for the gravity to keep them in the pan, cleanliness of the fluid would be the least of your concerns.
 
I find if doing that first cleaning at 20k - new filter and adding a drain plug - I can get to 60k by just dumping a pan volume here and there -
Normally the magnets were worse at 20k (break in metal) than with twice the miles (20-60) …
Yes, once things are broken in and "clean" then maintenance cycles can be reduced.
 
This mostly happens during break in. That’s why I’m a proponent of dropping the pan early in the first 20k miles or so.

After that, the magnet will be good for a long, long time like 100k miles. No need to drop the pan just to clean the magnets. Regular fluid changes will be more than enough to keep the fluid clean.

As far as the pan goes, the particles are simply too small to stay at the bottom, they will always be picked up by the fluid. And if you have chunks big enough for the gravity to keep them in the pan, cleanliness of the fluid would be the least of your concerns.

If you drop the pan after a year and it, and magnets, are "clean enough", then try again in 2-3 years. Find an interval that works for your application and doesn't allow for excessive wear.
 
I have never dropped the U660F pan on my 2010 w/225k km and don't plan to ( I got it with 75k km). The unit received regular drain and fills and most likely had it done the very last time several years ago, because the fluid* came out as clean as what went it in. I'll be looking for a replacement vehicle in 2 to 3 years anyways.

*MaxLife Dex/Merc.
 
First off, I would Never mix fluids the oem fluid is your best chance at longevity, especially when serving a CVT.
Your service intervals are perfect, just mixing chemical compounds is a poor dilute
 
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