Transmission Fluid/Filter change

[Arnoldtheskier]

Caught this on a VERY! popular car talk radio show.
This guy is a real honest,popular,independant, transmission servce specialist.
"We get customers in here ALL the time who JUST had their transmission fluid,filter changed..and THEN SOON AFTER..transmission failure.IF you are simply going to change/have it changed.. the fluid,filter on a car that has gone 100 to 150 K's.We reccomend to NOT change it until there is a problem.The problem is with modern cars and transmissions running so hot..plus the complexity of the transmissions(solenoids,finer valve bodies,computers controlling/adjusting and adapting to changes)the longer the fluid is in there..especially the "cycling" of hot/cold as in a winter climate like here.Transmission fluid breaks down..varnish from it begins to get by the filter and stick to not just the plates but the solenoids.The longer this has gone on the greater the problem.This often affects transmission operation BUT the transmission and computer can adjust somewhat.
When the fluid,filter is suddennly changed..a lot of the gunk that was in the transmission..or stuck to parts now gets recirculated.Valve body parts,solenoids..can NOW move or get stuck faster than other components can react causing internal pressures to rise too high too fast resulting in failure.This is common on the first very cold day after the fluid,filter change.
"Flushing" is only somewhat beter as this ONLY deals with the gunk in their RIGHT NOW.There needs to be a time when the car is driven AS the fluid is changed to get ALL the muck in circulation to be drained/filterred outl
We reccommend draining or siphoning out(through the dipstick) about 2 quarts and replacing it.Driving a few thousand k then draining or siphoning out the rest and replacing it.Driving again another few thousand k and this time be prepared(or already have a drain plug IN the convertor).This time..DRAIN all the fluid including the convertor,change fluid,filter.More meticulous maintenance/severe abuse/very expensive transmissions should also after another few thousand k's have a flush.
This GRADUALLY changes the transmission fluid..allowing plenty of time to adjust and for most of the muck to get into a soluble form or caught by the filter and removed.

Sounds good to me.LOL..this is what I do NOW.Bit more work and $ but can't hurt and seems like cheap "insurance"

[Davescort97]

Good advice, but sometimes the muck is the only thing keeping the clutch assemblies working. I would advise against pulling the plug on the converter if it has one. They usually leak after being put back in. If you want to drill a hole in the converter and put in a new plug that would work.
Replacing the fluid on a gradual basis seems like a good idea to me. I've seen a lot of varnish on trannies from over heating.

[fishing1000]

Originally Posted by Davescort97

Good advice, but sometimes the muck is the only thing keeping the clutch assemblies working. I would advise against pulling the plug on the converter if it has one. They usually leak after being put back in. If you want to drill a hole in the converter and put in a new plug that would work.
Replacing the fluid on a gradual basis seems like a good idea to me. I've seen a lot of varnish on trannies from over heating.

You can drain the fluid on an escort very easily. On a dodge caravan, I just disconnect the hose that goes from the tranny to the radiator and turn the engine on to 'pump' the fluid out. It only takes a minute or so to get 3 quarts out of the trans. My friend, a mechanic, told me to replace a few quarts every 15 k miles.