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Transmission Flush, good idea ???

06-10-2004, 03:10 PM
I just had an oil change done on my 2001 Sport that I have had for a week now. It has 118 Km (74 miles) on it and runs great. The dealer did a 50 point inspection on the van and came back with some recomendations.

1) transmission flush
2) coolent flush
3) power steering flush

Any thoughts on what would be a good idea to have done at this point. I have no service records so I have to assume nothing has been done to the van. Too do all 3 would cost close to $400 cad.(dealer cost) I'm not looking to spent anything right now, but I know some maintance is a good idea.

Any feedback would be great.

06-10-2004, 09:38 PM
#1 & #2 are a MUST at this point if you want your van to last. #3 is also a good idea since the p-steering systems on these vans run so hot. All 3 were dirty and nasty by 36000miles on my 2001.

06-11-2004, 07:58 AM
There are some arguments against transmission flushing. The theory goes that the flush loosens trapped gunk and dirt particles that then float around and embed in the valve body etc causing sticking valves etc. My opiniion is that the flush is a good idea. You can do it yourself; involves draining the fluid, filling it, disconnecting the outlet line to the cooler and then adding fluid while the transmission pumps its fluid into a container thru the line. Flush about 12-15 quarts through the unit then, close it up and fill to appropriate level.

Flushing the coolant is always a good idea and the more often the better.

I had my power steering system flushed at 40, was dirty nasty and smelled burnt. I will continue to do so every 20,000 or so.

06-11-2004, 10:34 AM
Here are my suggestions, and the reasons for them:

#1: NO! Don't "flush" it, don't change the ATF, don't do ANYTHING unless the fluid is already clean and does not smell burned. If you leave ATF in a trans. for more than about 60,000 miles, it is degraded to the point where changing it may very well CAUSE the trans to fail. This is a chamical precess, and while I don't know everything about it the result is that with new fluid the clutches will slip, and it will burn them up. ATF gets more "grippy" as it ages, and very old fluid (60,000 miles +) is MUCH "grippier" than new fluid, and that is the problem.

Now, if your fluid is CLEAN, and smells good without a hint of bein burned, then it should be OK to CHANGE it. When you are unsure about the actual age of ATF, it is a VERY bad idea to completely change even good clean, but old ATF 100% with new. Have the pan drained, and that amount replaced, or if you are a "backyard DIY" type of person, pump out the pan youself, and fill it back up.

#2: Definately! This again, is easy to do, and something you don't need to pay someone else to do, but you certainly could.

#3: Yes. However, you can accomplish the same thing with a "turkey baster" over a couple days by sucking the PS fluid reservior out, and replacing with fresh "Mercon/Dexron" ATF. Three or four times will get about 90% of the old fluid out.

06-11-2004, 03:49 PM
With #2 & #3 you can get it flushed or just DIY.

With the ATF flush, a friend of mine who works for Cottman Transmissions for a long time, does not recommend it...anymore. They used to do it(Wynns) but not since they noticed problems with their customers tranny. He sold their flush machine and just does the regular ATF change now. He believes that flushing with those 'express' flush machines, aside from cleaning out the crud, also strips the gears too much of the essential film of lube fluid already coating the metal. He recommends just changing the fluid($40) every 35K-45K miles and cleaning the tranny pan/filter. It's also cheaper than so-called flushing service. Again if you're a DIY'er you can simulate a safer flush as mentioned on above posts.

BTW, had my tranny rebuilt by them on my '99 after damaging gears & failed sensor. That's when he told me about his opinion on flushing. Prior to that I've had it flushed by a Goodyear or Firestone shop for $80.

06-11-2011, 01:26 PM
I have been lurking for quite some time, just reading. Congratulations, this thread made me actually join and chime in. Sorry about the length.

You have several opinions, some based on fact, some based on urban legends and the like. If the fluid has been changed regularly, that is great if not then it certainly needs it. ATF is just like engine oil in the sense that it breaks down over time. If you do not change it, then your fluid is not doing it's intended job. Its job(s) are creating a hydraulic lock to move your car, cool your transmission and lubricate your transmission. The optimum operating temperature for a transmission is approx 160 degrees. Since most cars use a fluid cooled system that is piped through the radiator, in most cars your best case scenario is about 195 degrees. You are already killing your fluid from day 1.

If you change your fluid, and it the transmission fails, you already had problems. Do not listen to anyone telling you not to change it. That advice is certain to get you a dead transmission. I recommend changing your fluid at least once a year. Flush it every year if you can afford it. Remember fluid is cheaper than metal. Make absolutely certain that who ever does the flush replaces the fluid with the proper fluid designed for your car. DO NOT LET JIFFY LUBE OR SIMILAR PLACES DO THE FLUSH! If you do not have a trusted mechanic, take it to the dealer. The at home self flush is not recommended. Their are certain commercial chemicals that are not available to you. The flushing machines use these chemicals to break up the deposits that over time get deposited in the torque converter. These deposits need to be removed to preserve the life of your transmission. Your first flush should also include a filter change. More expensive, but well worth the money. Service about $200. New tranny about $1000 or more.

To further help preserve the live of your transmission. Add an external cooler, plate type preferred. You can also add an external filter, not as crucial, but it is convenient. Also use a synthetic fluid if there is one available for your car. Most important of all, CHANGE THE FLUID REGULARLY! I have never changed a transmission in my life and my current vehicle is almost 15 years old. Same motor and transmission. Good luck.

12-12-2011, 12:13 AM
flush your trans yourself.all fluid being poured back into the trans,is replacing all the dirty oil being flushed far as debri coming loose and clogging up you valve body is hogwash.the fluid is being pumped out into a bucket and cant get back inside.i have been doing this for 40 years and not only save a bunch of money,but my trans runs at it best.i run thing since sliced bread.they perfected the stuff and have improved on it for line and royal purple are also say expensive,price a rebuilt tranny,and you still dont know if the idiot rebuilding it knows what their doing.40 plus years and ive seen and heard it all and most of it is just plain stupid.on new cars today,with closed systems follow the book.all older vehicals change the fluid and keep it changed.its a set of gears,bands clutches gets dirty,loses its additives and loses the cooling effect.also run at least an external air cooler after it leaves the radiator.i have a 47 willys pickup,i built as a tribute to the gasser wars of yesterday.i run a big olds,built turbo 400 3 speed and a posi 9in ford. i run an aluminum radiator and an external cooler only.i have had this on the road for 5 years and just flushed my trans and the inside of the pan couldnt have looked better.not a sign of over heating the fluid.i drive it winter and summer and at all kind of conditions and secret.i keep amsoil,or royal purple in it and change it about every 50000 miles.this trans was rebuilt almost 9 years point,flush it, and use good synthetic and keep it COOL!!

01-13-2012, 03:21 PM
I think the issue with transmission fluid is the effect on the pump which is what usually fails. You start losing fluid pressure and the clutches do not hold nor does the transmission shift properly.

So if the fluid is getting thin and losing is lubricating ability, the pump is going to wear excessively.

Flushing -v- Changing: Don't know about this Flushing technology - may be good, maybe be bad. But Changing is another matter - I think it is win/win.

01-14-2012, 06:52 PM
The term "Flush" is used loosely in the business.
MOST places use a machine that is connected into a transmission cooler line.

Then your vehicle is started up and run at idle.

The fluid is pumped out the cooler line by the vehicle's transmission fluid pump......and into the machine.

The machine then adds new fluid into the return line to the transmisssion at the same rate that the old fluid is being pushed out.

THIS is the service that you want.
You do NOT want to add ANY chemical cleaners.....just a high quality fluid that is listed for use in the Mercon V specification.

This fluid EXCHANGE needs to be done at LEAST every 30K miles (21K miles for "severe" service)

big white bufflo
01-15-2012, 08:16 AM
Im a old school person i prefer to change fluid and filter every one as valate point in flush or change when theyflush they do not drop the pan and change the filter there for all sedimet in pan stay in pan will not go through the filter and when they flush they revers the flow of fluid losening all dirt and metal thus putting them in limbo to go some were else valve ,clutch or back in pan . i have a 92 buick original trans 205000 never flush just change fluid so im for change fluid and filter

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