transmission fluid change

[mr. seaview]

i was wondering if anyone has a set rule on changing treansmission fluid?

my fluid still looks good and does not smell burnt. i have about 43,000 miles
on my 99 seaview and have never ever changed the transmission fluid.

i have added some fluid on some long trips but was wondering if i should
change the transmission fluid and the transmission fluid filter? motorhome
seems to run good and does not overheat and i know it has a transmission
cooler on it that i assume is working properly?

just want to prevent any transmission problems in the future as i know that
transmission work is expensive. thanks for any input and opinions.

[60sumtin]

I'm assuming you mean an automatic transmission. 44,000 is not a lot of miles. But if you have to add fluid occasionally that means its leaking somewhere. Unlike an engine trannys don't consume oil thus many new vehicles don't even have a transmission dipstick. Get the leak fixed then a complete flush with filter. Just dropping the pan to change the filter doesn't drain all the fluid thus its only a partial change.

[Winemaker2]

Best advice is follow mfg recommendations.
What tranny mfg?
Allison recommends fluid $ filter change but no flushing.

[Mr_D]

Too many transmission problems occur after a flush. I'll never have it done to any vehicle I own.

[Scooter]

Assuming you have an Allison trans.....there is a section just for you... on this forum.

[John Wayne]

The filter in the trans is like a screen doesn't filter the fine stuff. I added a inline filter NAPA (magnefine) #1-8721. This is the same one Ford requires to be added if the Trans has ever been rebuilt. Then I just drain the pan and change the filter every 20,000 miles. About 7 Qts trans fluid.Fluids are cheap insurance trans rebuild is expensive.

[FredV]

If the Trans is an Allison there may be an external screw on filter which I would change at 25K to 50K. It should also have an in pan filter that I would change at 75K. Automatic Transmission fluid has detergents and seal conditioners in the fluid. Flushing and adding new fluid can cause already weak or deteriorated clutch material to be removed from the wet clutches and bands in a Transmission which ends up plugging the filter. It can also cause valves in the valve body to become stuck and shift solenoids to become plugged. Having said all this and assuming that the fluid in your trans is not burnt and it is shifting properly I would only replace the external filter and plan on replacing the internal filter at 75K. Refill trans and DON'T flush. Same advice applies to Ford if nothing has been done to trans.

[geoff1200]

Originally Posted by John Wayne

The filter in the trans is like a screen doesn't filter the fine stuff. I added a inline filter NAPA (magnefine) #1-8721. This is the same one Ford requires to be added if the Trans has ever been rebuilt. Then I just drain the pan and change the filter every 20,000 miles. About 7 Qts trans fluid.Fluids are cheap insurance trans rebuild is expensive.

I concur, owned a transmission shop in a previous life. I advocate simply draining tranny annually or every engine oil change.