Question Hope you can help I would like to have the tranny fluid and filter changed in my vehicle is it wise to have a tranny flush done by machine is this safe to do to a tranny or may it lead to problems down the road. Is it safe to have done to any vehicle?
AnswerLarry,
I think that transmission flushing is one the most flagrant rip-offs to come along in many years.
My personal vehicles have drian pans with drain plugs (I purchased the drain pans aftermarket, but drain plug kits exist). I simply remove the plug every 10,000 miles and drain about half of the transmission fluid. I refill with new fluid and drive another 10,000 miles.
Keep in mind that I do this on vehicles that had 60,000 mile fluid and filter change intervals except if towing. Towing change interval was recommended at 12,000 miles.
Many vehicles today have 100,000 mile transmission fluid and filter change recommendations. The fluid has gotten better and transmission design has improved to allow the longer service interval.
Flushing is only necessary when the fluid has been burnt from overheating.
And, yes, a transmission that has been overloaded/overheated may go into "fluid shock" if the fluid is replaced. Some transmissions will slip and other will not work at all if that happens.
If you are a do-it-yourself type person, you can buy a transmission filter kit with the gasket at any auto parts stores. The store can tell you how much transmission fluid you will need and usually the entire cost will be under $30 for the parts.
The worst part of the job is remving the pan since the fluid will run out everywhere around the perimeter. You can do this job with the transmission cold and loosen the bolts starting at one corner and working you way out evenly on both sides from the corner. Take your time and let the fluid drain as much as possible before removing the pan.
Follow the instructions to change the filter and then put the pan back on the transmission WITHOUT using any sealer. Tighten the bolts evenly and moderately. Refill the transmission with all but a quart or two of the recommended amount of fluid and then start the engine. Add only enough fluid to bring the level up to the correct mark on the dipstick. Do NOT overfill the transmission.
$30 is a lot better than the $100 to $170 price for a flush. If you feel it is necessary to change the fluid frequently, you can buy just the pan gasket or install a drain plug. The filter only needs to be changed about every 50,000 miles.
