how offten should you do a tranny service? i have a 02 civic ex with 95k looks like the 1ST OWNER DID IT EVERY 15K MI.

 

Depends on the use. But I do mine every 50,000 miles. I'm not sure what the owners manual says but I'm sure it is more often that I change mine.

 

I can't speak directly to your 2002 since my Civics are 6th generation ('96-'00), but this issue is probably no different. The Service Manual for my Civics says to change the MT or AT fluid every 90K mi and the CVT fluid every 30K mi under normal driving conditions. Under severe conditions, the MT and AT fluid is also changed at 30K mi, and if you drive fast in the heat a CVT owner should do the change at 12K mi.

So, what is a change? As far as I can tell according to Honda a transmission oil change is a single drain and fill. For my cars a drain removes 2.9 qt of ATF and leaves 3.3 qt of old ATF behind. In other words, each drain and fill removes about 47% of the full ATF capacity. Therefore, it takes 3 drain and fill procedures to refresh 85% of the ATF, 5 to refresh 95%, and 6 to refresh 98%.

It doesn't seem right to do a single drain and fill every 90K mi, and a flush isn't supposed to be good for the car. If you do 6 drain and fills over the 90K mi interval you will essentially renew your transmission fluid, well at least 98%. So that's why the previous owner did a drain and fill every 15K mi, i.e., 90Kmi/6 = 15Kmi.

 

90K between services?? That is way more than I would of ever guessed. My 90 Civic has 155,000 & I have serviced it twice. The fluid is nice & red. Honda builds some good A/T that is for sure.
I'm going to get 300,000 out of it. Wish me luck.

 

Ive never heard a person say that in all my life.

 

Another reason why the 1st owner did a drain and fill every 15K mi.