any helpful hints on tranny filter change ?

Well the boy's 92 lumina ( 3.1 auto trans ) may benefit from a filter / fluid change. It's the traditional 18 year old's college car, pushing almost 200k. The fluid is not burned but has the darkened look of being in need of a change. It still smells ok however. He said it's starting to go into neutral at stop lights every now and then. We've done good maintenance on all the rest and it runs well and is a pretty decent car.

I know you don't do a full fluid change / flush or the rest. I just want to change the filter and refill with what fluid is lost out of the pan when I pull it off, as that is the best and only way to go with a high mile vehicle. I hope the problem is just older fluid and the filter getting plugged up with the years, reducing the flow and pressure.

Please don't scare me on "your tranny is going out, rebuild, etc" as I want to try the simple replace/refill method ..

Just asking on "by the way's, do this first, don't do this, and all the rest that will help my in the garage on Sunday afternoon.

Thanks Guys !!!

stanley i saw this discussed in depth on this forum or elsewhere. it seems about 99% of the guys told me not to change anything on my 1998 lumina(80 k miles)tranny or risk total rebuild. from the sounds of your situation however,it seems you ain,t got much choice.

Well the boy's 92 lumina ( 3.1 auto trans ) may benefit from a filter / fluid change. It's the traditional 18 year old's college car, pushing almost 200k. The fluid is not burned but has the darkened look of being in need of a change. It still smells ok however. He said it's starting to go into neutral at stop lights every now and then. We've done good maintenance on all the rest and it runs well and is a pretty decent car.

I know you don't do a full fluid change / flush or the rest. I just want to change the filter and refill with what fluid is lost out of the pan when I pull it off, as that is the best and only way to go with a high mile vehicle. I hope the problem is just older fluid and the filter getting plugged up with the years, reducing the flow and pressure.

Please don't scare me on "your tranny is going out, rebuild, etc" as I want to try the simple replace/refill method ..

Just asking on "by the way's, do this first, don't do this, and all the rest that will help my in the garage on Sunday afternoon.

Thanks Guys !!!


You are on the right track.
Just the filter change can may help.
If the filter is stopped up it will burn up a lot sooner if you do not change it.
Good luck and let us know how it goes.

Definitely change the fluid and filter, would be helpful to know which trans this is, either a th125c, or a th440t4. The latter is an overdrive trans(4speed), and is controlled by vacuum. If you are neutralling at stops, that is and indication of low fluid, poor engine vacuum, or a clogged filter. Change the fluid and filter. 5 quarts on the 125, 6.5 quarts on the 440, DO NOT PUT ANY ADDITIVES IN THE TRANS. I've been a trans rebuilder for almost 20 years, and these additives are the worst possible thing anyone can put in their transmission. Oh yeah, stop at your local tranny shop and purchase a gasket, ask for a duraprene gasket, the ones you buy at these parts houses are crap, clean the pan and magnet thouroughly, and don't use any gasket sealer on the pan, this will really screw it up if any of that gets stuck in the filter.:smokin:

Thanks guys,

The tranny is the automatic with overdrive (4 speed). I plan to really clean the pan and magnet with acetone, letting it dry completly. When it comes to gasket sealer... I'm from the old school and use copper coat spray on, letting it set up far away from the tranny.

Is there anythig I should be aware of like being real careful with any filter connections, taking my time on getting things loose, unstuck, and the rest ? I think I recall from other post's.. something about a plastic connection or something that has given other folks trouble ? I live in the country and don't want to make a trip back to town for something else.
As always....... information is much appreciated !!!

Stan

Thanks guys,

The tranny is the automatic with overdrive (4 speed). I plan to really clean the pan and magnet with acetone, letting it dry completly. When it comes to gasket sealer... I'm from the old school and use copper coat spray on, letting it set up far away from the tranny.

Is there anythig I should be aware of like being real careful with any filter connections, taking my time on getting things loose, unstuck, and the rest ? I think I recall from other post's.. something about a plastic connection or something that has given other folks trouble ? I live in the country and don't want to make a trip back to town for something else.
As always....... information is much appreciated !!!

Stan

A big or bigger drain pan helps.
The filter should/will come with a seal for filter neck to case.
To get the old one out take a small chiseal or screwdriver and knock the outer steel lip on old seal in from the side and pull old seal out.
The filter just pulls down and plugs in the transmission case
A 7\8" 15\16" socket upside down makes a good driver to install new seal.
On the gasket as as said a filter kit has a junk gasket.
Get a good one or if it has the thick rubber and steel resuable gasket on it just reuse it.
Copper coat is a good gasket sealer but on transmission pan gaskets it is better to put them on clean surface and dry.
Make sure you get it good and hot and drive it 15/20 miles for the final fluid check.
And if a vacume modulator valve on it check vacume and vacume line for oil in it.
Good Luck MT