Trans flush?

How come after a certain milage (ive heard 70k, 100k, 50k) people say you shouldnt change or flush your trans fluid.
Is this true or just another stupid car rumor?
And if so how come.

I've heard it both ways. Some people swear they've had trouble after a flush while others insist that you must do it on schedule every time. I personally have never had a problem after doing a fluid and filter change. However, I can see how a flush might dislodge some build-up which may result in leaks and other problems........kinda like switching to synthetic motor oil after having used mineral for 100,000 miles.

Cass,
I have a feeling that he means, if you change it the trans will slip. That's always been the big fear. I try to change about every 40,000 miles. Last time is when the shift kit went in. Everything is working great.
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP004.jpg

I change the fluid and filter per the maint schedule but have never had it power flushed. I've heard some folks have had seal problems after a flush.

Never had it power flushed. If it changed as it should be, shouldn't had to power flushed
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP002.jpg

I just purchased a 2000 GTP Daytona Pace Car. I power flushed my trans because I didn't like the color of the fluid,very light tan. The car has 99,540 miles on it. The flush place told me that they don't like to flush cars with over 100,000 miles and that I just made it. I have put 280 miles on it since the flush with out any problems. I have a 1980 Lincoln that I flushed because the fluid was brown when I got it. Also, it would feel like when it warmed up it wouldn't shift as firm as when it was cold. After the fluid change the shifts remained firm. I believe the old fluid couldn't handle the heat properly. I haven't had any trouble with it.

The flush is better for the shop doing the work because they don't have to fight getting the pan off,,,,broken bolts,,,,leaky pan gaskets,,,AND
dreaded contamination of the valve-body when replacing the filter!!!
The bad part for you,,,,You still have a questionable filter in there,,,,
and the magnets are STILL full of gunk!!!! When the fluid & filter is changed,,,the filter is new,,,the magnets are clean and able to collect debris!!!!! If the trans fails after servicing,,,chances are really good
that it needed alot more than an oil change!!!!!!!!!!!!!!!!!!

I'll change that filter tomorrow.

Power flushes are never good. Sometimes what keeps your tranny going is the particles that are holding it together. After I blew mine up I made sure I added a shift kit... The GT trannies are pieces of shit. Well the diff and the input shaft are

I have two Transports that I had a power flush done to when I first got them. They are 1992's. one had 94,000 on it when I had it done and now it has 149,000 and is shifting great. The other had 78,000 on it when it was flushed and now it has 127,000 on it with no problems at all.
I think that if patrticles are what keeps the trans running it's running out of time fast.
What shift kit did you use ? I want to pick up one for my 200GTP Pace Car. It has the performance shift option. I also want to pick a couple up for my vans. I didn't know they were available for FWD.
Thanks

most places that do trans flushes will make you sign a waiver if your car is over a certain mileage. I do not recommend doing a fluid flush, as the new fluid is grippier than the old fluid and can cause your clutch plates to shear off, effectively ruining your transmission.

I pulled an 18 foot boat with a 260 horse outboard on it with the Transport that has a 147,000 on it and no problems. The Transport came with the towing package, that probably helps. I already did the flush on the GTP the filter goes in today I'll keep you posted on what happens with it. Did you guys actually flush yours and run into problems or did you just hear about problems with flushes? I would think that if the trans is weak to start with nothing will really help especially the snake oils out there or just fluid changes. Quick engagements when a trans shifts is a good thing, less heat. The slow engagements are what causes heat and transmissions hate heat. Another vechile that I have is a 1994 Chevy dealer optioned SS350 pickup. I got that with 97,000 on it, had the trans power flushed, and I tow a 21 foot cuddy cabin boat with a 350 in it. The truck now has 119,000 on it and the trans shifts like new. I took it to us66 this summer and it turned 15.90 all stock. No problems with that trans yet.

Thanks for all the replys everyone.
I just bought my GTP with 60k on it and wanted some inpout on whether to flush or just filter change.
The fluid is still "pink and it dont stink". So I guess its probably already been done. But id rather do it now then wait until its too late.
Also any input on Sythetic trans fluid, any body here use it, notice a difference?

If you can have your trans fluid changed to synthetic do it. Synthetic fluids, oils, greases are far superior to any refined oil product. In a 5.0 Mustang changing the trans, rear end and engine over to synthetic was good for 10 more horsepower. Synthetics don't break down. I use synthetic s in every vehicle I own.