I have a 2003 Chevy Blazer. I did a transmission flush and filter replacement at 51000 miles. I now have 102500 and thinking about flushing it again. I planning to keep it about 3 to 5 years yet and average 10000 miles a year. No trailer towing or heavy hauling with it. To save some money, do you think I can just flush without replacing the filter?

 

I am against flushing the tranny, but that is me. In my opinion if you have just done highway or easy driving just dump the tranny pan and replace the filter and fluid that comes out. When on the farm had several trucks get tranny flushes and the trannys went out shortly after. Granted the tranny may have been almost gone but never know now.

But either way you go i would still change the filter if it were my vehicle. Spend a little extra to save lots later i believe.

 

Old skool - drop the pan change the filter and just refill the amount of fluid you drained by droping the pan - IMO clutches are worn to a extent when you flush a auto trans you rob some of the grittyness the clutches need to bite - on a low milage trans maybe ok but in a high milage trans NO - seen too many trans die with a full flush

 

It often seemed that people who are against transmission flushes, are against them because they had them done to try to fix a problem then have it done as preventive maintenance. I firmly believe in doing preventive maintenance, so to avoid the costly transmission repair or replace bill. I have done transmission filter change and a flush at 51,000 miles. No problems occurred because of that. Too do both at a service center is expensive. around $300 or less. So I went to look at my owners manuel and this is what it said at 50,000 miles or 15,000 miles in severe conditions: "Change transmission fluid and filter." That is all it said. Its obvious that you should change the filter and no where is flush mentioned. But when you do a pan drop, you only change 40% of the fluid, so a flush would be the closest thing to a fluid change. Does anybody have insight of this. Given my circumstance: easier local driving, some highway, no heavy loads or trailering, planning on replacing in 4-5 years while adding approximately 10000 miles a year, fluid is still red on dipstick(it was replaced with Wolfs Universal synthetic ATF on the last flush). What would be my best option? Do a pan drop and filter change? Do a flush? Or just bit the bullet and do a dan drop and filter change with a flush? Or do nothing, it is synthetic ATF and last to x number of miles?

 

- as we posted above and if were mine there is no way I would do a full flush, just filter and refill pan - I do however know there will prob be many here that will agree but in the same fact there will be just as many that disagree - your trans your choice

 

I believe that some of the people who had trans issues after a machine flush probably were victims of an old trans that was going out anyway or had the flush done awhile back by machines that are not used anymore in most shops. Technology has improved the machines used to flush transmissions.

That said, if an automatic transmission has ~100k on it without ever having had the fluid changed it might be safer to do a pan drop. Either way I highly recommend changing auto transmission fluid around every 30,000 miles. Most modern transmissions never see a filter change since the only thing that will collect on them is parts of the clutch packs which means its going to need rebuilding in the future, but if you do a pan drop why not change the filter while it's exposed.

 

A dirty filter will effect fluid flow and pressure, which in turn will effect shifting, change the filter if the pans off