Transmission Oil (To change or Not to change?)

Originally Posted by ryannel2003

Ditto here. I've got almost 152k miles and I'm pretty sure the fluid has never been changed. Transmission shifts fine though. Do you have the GM or ZF transmission?

According to the charts, I believe I have 5HP19 (A5S 325Z) being an 01. But have to go under the car to confirm.

If you're going to do a drain and fill, why wouldn't you also replace the filter? Sort of like changing your engine oil and leaving the old filter in place.

Originally Posted by Sansho

If you're going to do a drain and fill, why wouldn't you also replace the filter? Sort of like changing your engine oil and leaving the old filter in place.

Yah, if I go ahead with the drain and fill I will definitely change the filter.
I am just concerned about opening the perfectly working transmission, as plenty of horror stories of transmission going kaput after the fluid/filter change.

Originally Posted by PsychoCemia

1st drain/fill: 3.5qts old, 6qts new (63% new) - 6qts used
2nd drain/fill: 1.3qts old, 8.2qts new (86% new) - 6qts used
3rd drain/fill: .5qts old, 9.1qts new (96% new) - 6qts used
4th drain/fill: .2qts old, 9.3qts new (98% new) - 6qts used

So...to get ~98% new fluid, you'd need to use 24qts.

However, almost everyone is going to do just a single drain/fill, which will get about 2/3 of our fluid replaced. Even for the most diehard folks, it doesn't make any sense to do more than 2 drain/fills.

Well, I'm far from diehard, but I did 3 changes. I reckon the third change from 86% to 96% is significant, but the 4th only improves 2% and it is not worth it. 3 changes (18qts) are preferred DIY method.

... I am just concerned about opening the perfectly working transmission, as plenty of horror stories of transmission going kaput after the fluid/filter change.

[start contrarian thought for the day]

Yeh, understand that, but you know .... show me someone who changed their fluid and filter and had an issue. I'm not saying it doesn't happen, but I wonder if it hasn't become almost a wives tale, so to speak. In the several years on this discussion, I don't recall anyone changing their fluid after 100K and posting that their transmission failed. While wives tales have some basis in reality, they can sometimes get blown out of proportion over time.

[end contrarian thought for the day]

I had a torque converter failure about 2 1/2 years ago. Took out the front pump when it failed at 58,000 miles. I rebuilt the ZF box myself and used Valvoline Max Life Mercon VI fluid. I now have 75,000 total miles on the car without any problems. I plan to change the fluid and filter again at 80,000 miles. This will put my first change at 22,000 miles. I do not expect any further problems with this issue. The torque converter failure was an oddball occurrence and after talking to many transmission techs, no one had ever seen one do what mine did. The stub that drives the front pump swelled and took out the seal ring, ruining the pump. Everything inside miked standard, even the drive and driven clutches. There was no wear or stress evident on the reverse drum either. My car was built on March 29, 2000, so it already had all the upgrades that were not on the early versions. Go ahead and drain and change the filter. DO NOT FLUSH THE TRANSMISSION EVER!!!!!!!!!

Originally Posted by Stickbuilder

I had a torque converter failure about 2 1/2 years ago. Took out the front pump when it failed at 58,000 miles. I rebuilt the ZF box myself and used Valvoline Max Life Mercon VI fluid. I now have 75,000 total miles on the car without any problems. I plan to change the fluid and filter again at 80,000 miles. This will put my first change at 22,000 miles. I do not expect any further problems with this issue. The torque converter failure was an oddball occurrence and after talking to many transmission techs, no one had ever seen one do what mine did. The stub that drives the front pump swelled and took out the seal ring, ruining the pump. Everything inside miked standard, even the drive and driven clutches. There was no wear or stress evident on the reverse drum either. My car was built on March 29, 2000, so it already had all the upgrades that were not on the early versions. Go ahead and drain and change the filter. DO NOT FLUSH THE TRANSMISSION EVER!!!!!!!!!

Do not flush the transmission ever? What do you mean? Because how else can you get most of the old atf out?
By the way, how can I know what tranny I've got, ZF or GM? I've got a 1999 323i made in march 1999
Best regards
Rod

Originally Posted by rodster

Do not flush the transmission ever? What do you mean? Because how else can you get most of the old atf out?
By the way, how can I know what tranny I've got, ZF or GM? I've got a 1999 323i made in march 1999

You have a GM transmission. People usually do not flush the tranny because the fluid is too expensive (if you used the original stuff) and not needed.

I've got a 1999 323i made in march 1999

The GM A5S360R transmission was used in the 323i from 7/98 thru 3/2000, which is spec'd for Texaco ETL 7045E fluid.

You can confirm this by the label on the transmission pan. See this for more info.

Originally Posted by scottjoh

You have a GM transmission. People usually do not flush the tranny because the fluid is too expensive (if you used the original stuff) and not needed.

Aw! OK I get it ! thanks!

Originally Posted by Sansho

The GM A5S360R transmission was used in the 323i from 7/98 thru 3/2000, which is spec'd for Texaco ETL 7045E fluid.

You can confirm this by the label on the transmission pan. See this for more info.

Thanks to both of you for the info, it's good to know that at least my car doesn't have the dreaded no-reverse issue although it's still not immune to "issues"; the reverse solenoid can fail. I'm just in the process of changing my tranny oil, I got the filter, gasket and 10 quarts of "Pentosin" synthetic. I can't find many quotes on Pentosin tranny oil here but from the research I've done it looks like it's spot on as the correct oil for my car's GM tranny. 10 quarts isn't enough oil for a flush and refill, I think I need at least two quarts more with no margin for error. Perhaps I should buy another 5 quart container from the same seller.
I am afraid of the oil change, I must admit it, although thanks to this place I understand it's the best thing I can do for my tranny. It's not giving ANY trouble at all, Works fine but I know it's never been changed. My 1999 323i has 108K miles and it's all in excellent condition.