Will changing ATF mess up Transmission?

[newlano]

Hi,
I read that changing your ATF will "shock" your Auto transmission and cause pre-mature failure.The article stated that the new ATF should be gradually introduced int9o the tranny. Is this true? I have a 1991 525i and was thinking about the complete flush that places like Pep boys offers. Any of your experiences will greatly help.

[jjw]

Yes it can, especially if the ATF has not been changed regularly or long time. The trans might be holding together because the old ATF.

[Russell]

Had my indy clean screens pans and change transmission filter, DRAIN both pans in transmission (no flush) Torque convertor is not drained and new standard dexron III fluid ATF at about 73,000 miles. It was the first change and had no problems. 30,000 mile later same routine, except I use Mobil 1 Synthetic Dexron III atf. No problems, perhaps a smoother shift. My GM trany should be changed every 30,000 miles.

Just my experience.


Hi,
I read that changing your ATF will "shock" your Auto transmission and cause pre-mature failure.The article stated that the new ATF should be gradually introduced int9o the tranny. Is this true? I have a 1991 525i and was thinking about the complete flush that places like Pep boys offers. Any of your experiences will greatly help.

[632 Regal]

I wouldnt flush it but do as recommended, change the filter and only replace what fluid came out...every 30k or so. If it has been changed every other oil change than of course you can change it.

[infinity5]

I don't think my transmission fluid has been changed since the car was born, but i think i'm going to go for it. i won't flush it, but i'll change the filter and whatever fluid drains out.

I'd kind of a littel skeptical of this whole idea of killing the transmission by changing its fluid just becuase it hasn't been done before.

[632 Regal]

I have seen transmissions fail from shocking it with new fluid...its real and NOT a hoax.

[dacoyote]

I have seen the shock of the flush kill tranny's... you need to change a part of each time..

-Charles

[gtopaul]

We don't do transmission fluid changes or filter changes at work because of the possibility it won't come off the rack when finished. I've seen it happen with just draining the fluid out of the pans and not just flushing. Every time we have to go into a trans to replace a bad valve body or something we tell the customer what could possibly happen (worst case scenerio) and let them make the choice. It's usually a bad front pump seal on the early auto trans that causes this. Tech said something about it looses it's prime when the fluid is drained. I personally think that if it's going to die it's going to die and there's not much you can do. I have 180k miles on my 92 525iT that is slow to engage reverse (about 2 seconds), and stays too long in 2nd gear before shifting. I've used the flush method on my other two cars (Volvo's) one with 142k and the other w/100k miles without any problems and they both shifted better afterwards. The 140k mile car has the ZF HP22 same as the early 525's and it was slipping badly. The flush fixed it right up and it's been fine for the last two years. I'm going the flush method and I'll be sure to let you all know the results. Hopefully next week.

Paul

[gtopaul]

Here's some good information about trans flushes.

http://www.autotransflush.com/

[Kalevera]

Paul, don't you work for a dealer? So the dealer won't do trans fluid and filter changes on cars that they sold new? That is...REALLY...suspect, albeit it affirms everything I know about them.

best, whit

[gtopaul]

Paul, don't you work for a dealer? So the dealer won't do trans fluid and filter changes on cars that they sold new? That is...REALLY...suspect, albeit it affirms everything I know about them.

best, whit

I believe BMW considers the new models with automatics as sealed units and not requiring regular maintenance according to the Inspection 1 and 2 requirements. If the cars are still under warranty and have a transmission problem BMW just sends us another one to install. Occasionally we have problems with the programming in electronically controlled transmissions and we can do some updates and resolve most of those. Also sometimes a valve body problem might crop up and BMW will send us another to install but that's about the only time we have the pans off. I remember someone with a Trans Control indication lit up on an E34 and it was going into limp mode. Diagnostic computer indicated a negative ground problem on one of the internal valves. We ran the worst case scenario by him and told him that the repair might fix the initial problem but the car might not move off the rack because of draining the fluid. He agreed to try and we did the work. He had no problems afterwards and the transmission shifted like new.

I guess the dealerships philosphy about all this is the only thing most customers understand about draining the trans fluid is they drove the car in and now it won't drive out. It's no fun to tell someone that they need a trans when all they wanted was clean fluid. Once you've had to buy a couple of transmissions because of this it is just smart business sense not to invite additional expenses for either the customer or dealership without everyone agreeing to what could happen before the work is done.

Paul
94 540iA
92 525iT

[Russell]

Mine was first changed (drained with atf/filter) at 72,000 then 103,000 or so with no problems. No flushes. My manual clearly states change transmission fluid changes every 30,000 miles. So I am just lucky?

It seems really odd that thet the dealer will not (or is it advise against) maintain older cars according to the manual. That said, I understand their caution with older "under maintained/abused" cars. I supect there is something to the old "flush and fill" could kill such a transmission.

Just my take.



I believe BMW considers the new models with automatics as sealed units and not requiring regular maintenance according to the Inspection 1 and 2 requirements. If the cars are still under warranty and have a transmission problem BMW just sends us another one to install. Occasionally we have problems with the programming in electronically controlled transmissions and we can do some updates and resolve most of those. Also sometimes a valve body problem might crop up and BMW will send us another to install but that's about the only time we have the pans off. I remember someone with a Trans Control indication lit up on an E34 and it was going into limp mode. Diagnostic computer indicated a negative ground problem on one of the internal valves. We ran the worst case scenario by him and told him that the repair might fix the initial problem but the car might not move off the rack because of draining the fluid. He agreed to try and we did the work. He had no problems afterwards and the transmission shifted like new.

I guess the dealerships philosphy about all this is the only thing most customers understand about draining the trans fluid is they drove the car in and now it won't drive out. It's no fun to tell someone that they need a trans when all they wanted was clean fluid. Once you've had to buy a couple of transmissions because of this it is just smart business sense not to invite additional expenses for either the customer or dealership without everyone agreeing to what could happen before the work is done.

Paul
94 540iA
92 525iT

[pyro]

Well i Risked it with my 88 735i w/ 285k miles it was never changed and was starting to not shift. i draind out 4 or so quarts and put that much back in shifted better than both of my parents cars after. What color is your fluit if its bright red then you should have no problems mine was brown...

[gtopaul]

We don't do transmission fluid changes or filter changes at work because of the possibility it won't come off the rack when finished. I've seen it happen with just draining the fluid out of the pans and not just flushing. Every time we have to go into a trans to replace a bad valve body or something we tell the customer what could possibly happen (worst case scenerio) and let them make the choice. It's usually a bad front pump seal on the early auto trans that causes this. Tech said something about it looses it's prime when the fluid is drained. I personally think that if it's going to die it's going to die and there's not much you can do. I have 180k miles on my 92 525iT that is slow to engage reverse (about 2 seconds), and stays too long in 2nd gear before shifting. I've used the flush method on my other two cars (Volvo's) one with 142k and the other w/100k miles without any problems and they both shifted better afterwards. The 140k mile car has the ZF HP22 same as the early 525's and it was slipping badly. The flush fixed it right up and it's been fine for the last two years. I'm going the flush method and I'll be sure to let you all know the results. Hopefully next week.

Paul

Well I took the plunge and scheduled the Bimmer for a trans flush down the block at the local KIA dealer. I know, but the KIA dealership was the only one with the good BG flush machine and cleaner and treatment additives. My total cost was $90 for the flush and additives and another $20 at O'Reillys for a case of Dexron III. Two days prior to the flush I started getting the old "Trans Program" lite which translated to a speed sensor error in the trans. I cleared all that out and it didin't come back but was still hanging in 2nd gear too long before going into 3rd. Since the flush the shifting has been getting more precise and quicker everyday I have driven the car. I only have about a two mile drive to work but I'll drive it more this weekend. So far things are looking up and I believe the flush route was worth taking the chance and the money. The car has 183k miles on it and the KIA tech said the fluid looked like it had never been changed.

This weekends project is replacing the catalytic convertor and 02 sensor and maybe, if I feel real motivated, changing the two power steering pump hoses which are leaking. ;-)

Later!

Paul

[Derek A.]

If burnt dirty trans fluid is holding your transmission together - its already shot.

[gtopaul]

If burnt dirty trans fluid is holding your transmission together - its already shot.

transmission fluid. Burnt is beyond help usually but dirty is just that, dirty. Doesn't mean it's hopeless as far as the trans goes. Besides, rebuilt auto only costs a grand + shipping but I'm not putting one in unless the old one breaks first. ;-) If I feel real goosey I'll change the trans filter next week and see if that kills it. If it's going to break I just as soon it do it quickly so I can install new trans and put wife in it. H&R touring springs will be here from Germany next week to get that in-the-air front end down.

Paul

[Robert K]

Our cars call for regular servicing of the fluids because the fluids get old, loose their original properties, and pick up contaminations. Because of all these things, and to prevent us becoming stranded on the side of the road, BMW and other manufacturers instruct us to regularly change fluids (oil, antifreeze, brake, transmission, differential, etc.) as a form of preventative maintenance.

The mechanical parts in our cars were designed to operate on new, clean fluids. When the fluids get old and nasty, the fluid can actually begin to make the mechanicals behave abnormally. This can especially be true in automatic transmissions. Therefore, I can't for the life of me understand how leaving old, nasty fluid in is actually better for your transmission.

I have a 1991 535i with the GM auto trans. I've heard these trannies aren't the best in the world which is why I service it OFTEN! Recently, I dropped the pan, cleaned the filter and wiped the small amount of fine metallic sludge out of the bottom of the pan (and I find that stuff in there every 10,000 to 15,000 miles when I drop the pan to clean or change the filter). I measured the amount of old fluid I took out and put in the same amount of new fluid. Then, I drove it a week, pulled the tranny pan drain plug and repeated the process. A week later I did the same. The only reason I didn't go find someone to do a tranny flush is because of the cost. At any rate, I believe my tranny shifted better having gone through this process.

My opinion is that you need to keep your fluids as new as possible. Since auto trannies do cost a mint (especially those with "BMW" cast into them), I think it is only wise to change the fluid often. I believe the same with the antifreeze and oil. I'm less concerned with brake fluid and power steering fluid, but I still do change those at the recommended intervals.

Although I never knew my dad's dad very well (he died when I was very young), one thing my dad says his dad always said was, "Lubrication's cheaper than parts." And he was a farmer. I've always remembered that and figured a regular dose of new fluids was better in the long run than infusions of expensive new parts. Just a few things to think about.

Grace and peace,

Robert K
1991 535i

[dacoyote]

Robert,

Want I am talking about is those people that do their first tranny flush at 100 - 150k. Those are the cars that don't come off the lifts.

In fact thinking about it, I will prop get mine looked at this winter, however with my 95 525i checking the tranny level requires werid tools and about 3billion steps. Chances are good that what I will do is swap out the filter and refill what I took out. Then take to KMS to have them check the level. (And get to see Whit again).

-Charles

[ryan roopnarine]

robert, if your transmission does not have a smaller front drain pan attached to it, it is not a GM transmission. i don't think that any 535i had a GM tranny. if you can recall when you changed your filter....if it did not come with two gaskets, your car is not equipped with a gm unit.


Our cars call for regular servicing of the fluids because the fluids get old, loose their original properties, and pick up contaminations. Because of all these things, and to prevent us becoming stranded on the side of the road, BMW and other manufacturers instruct us to regularly change fluids (oil, antifreeze, brake, transmission, differential, etc.) as a form of preventative maintenance.

The mechanical parts in our cars were designed to operate on new, clean fluids. When the fluids get old and nasty, the fluid can actually begin to make the mechanicals behave abnormally. This can especially be true in automatic transmissions. Therefore, I can't for the life of me understand how leaving old, nasty fluid in is actually better for your transmission.

I have a 1991 535i with the GM auto trans. I've heard these trannies aren't the best in the world which is why I service it OFTEN! Recently, I dropped the pan, cleaned the filter and wiped the small amount of fine metallic sludge out of the bottom of the pan (and I find that stuff in there every 10,000 to 15,000 miles when I drop the pan to clean or change the filter). I measured the amount of old fluid I took out and put in the same amount of new fluid. Then, I drove it a week, pulled the tranny pan drain plug and repeated the process. A week later I did the same. The only reason I didn't go find someone to do a tranny flush is because of the cost. At any rate, I believe my tranny shifted better having gone through this process.

My opinion is that you need to keep your fluids as new as possible. Since auto trannies do cost a mint (especially those with "BMW" cast into them), I think it is only wise to change the fluid often. I believe the same with the antifreeze and oil. I'm less concerned with brake fluid and power steering fluid, but I still do change those at the recommended intervals.

Although I never knew my dad's dad very well (he died when I was very young), one thing my dad says his dad always said was, "Lubrication's cheaper than parts." And he was a farmer. I've always remembered that and figured a regular dose of new fluids was better in the long run than infusions of expensive new parts. Just a few things to think about.

Grace and peace,

Robert K
1991 535i

[Rick L]

I had my trans fluid changed 15k miles ago and my car seemed to run better. I have 1995 525i trans with no dipstick (GM, I believe). Once in a awhile, when I'm cruzing around 55-60 m.p.h., the RPM used to go slightly up and down. This was rare but happens twice a week. I released the gas pedal and then resume to fix this problem. Now with new trans fluid, this problem is GONE... :)

[Robert K]

You may be right Ryan. I had always been lead to believe that it was a GM unit. Actually, I don't care who made it, as long as it keeps working fine! :)

Grace and peace,

Robert K
1991 535i