[tgeho_e92]

My car currently has 90k miles on it and it seems that the previous owners went with the lifetime fluid deal and never changed the transmission fluid or differential fluid. My question is will it cause more harm than good to put fresh fluid in both? I was reading somewhere that it could "shock" the metals inside and cause damage. I just want my transmission and differential to last as long as possible.

[bimmerfan1972]

Originally Posted by tgeho_e92

My car currently has 90k miles on it and it seems that the previous owners went with the lifetime fluid deal and never changed the transmission fluid or differential fluid. My question is will it cause more harm than good to put fresh fluid in both? I was reading somewhere that it could "shock" the metals inside and cause damage. I just want my transmission and differential to last as long as possible.

Interesting, I have not heard that. Hopefully not since I just did my transmission like 3 days ago.

[tgyberg]

I did it all just after 70k. Felt like the car liked it!

[tgeho_e92]

Originally Posted by bimmerfan1972

Interesting, I have not heard that. Hopefully not since I just did my transmission like 3 days ago.

Let me know how things go, how many miles on your dash?

[tgeho_e92]

Originally Posted by tgyberg

I did it all just after 70k. Felt like the car liked it!

You did both fluid changes? Trans and Diff?

[bimmerfan1972]

Originally Posted by tgeho_e92

Let me know how things go, how many miles on your dash?

122K

[tgeho_e92]

Originally Posted by bimmerfan1972

122K

You did both fluids?

[bimmerfan1972]

Originally Posted by tgeho_e92

You did both fluids?

I only did transmission. Also got a new pan with integrated filter as well (I have the ga6hp19z).

[tgeho_e92]

Originally Posted by bimmerfan1972

I only did transmission. Also got a new pan with integrated filter as well (I have the ga6hp19z).

Thank you!

[Pittz1]

I did all 3 at 150k. It was never done before. Smoother shifts and have had zero problems the last 30k.

[Vivek.]

Changing diff fluid will never harm anything. I've heard the same thing above on auto trans (could potentially cause issues if you change fluid) but I think that was more true for older transmissions in the 90's and before. Haven't heard of it on our cars.

[mapleleaf1773]

I have a 11 328 xdrive 117k miles. I changed both my diffs 2 weeks ago. I think the previous owners never changed them and the fluid was nasty dark.

My tranny is a manual, ill be doing that as well in the next couple weeks. A manual is a bit less worrisome to me than an automatic I dunno why.

Automatic transmissions have a filter that needs changing as well. I'd say change it, but that's me.

In the meantime I have vcg leakage, ugh. Time to change that first I guess.

[tgeho_e92]

Originally Posted by mapleleaf1773

I have a 11 328 xdrive 117k miles. I changed both my diffs 2 weeks ago. I think the previous owners never changed them and the fluid was nasty dark.

My tranny is a manual, ill be doing that as well in the next couple weeks. A manual is a bit less worrisome to me than an automatic I dunno why.

Automatic transmissions have a filter that needs changing as well. I'd say change it, but that's me.

In the meantime I have vcg leakage, ugh. Time to change that first I guess.

Yeah I'm a bit worried about automatic transmissions. CVT trans along with the traditional kinds in my experience have tanked at real low mileage.

I was reading that BMW claims a lifetime fluid but only rates "lifetime" as 100k miles. I don't know how much truth there is behind those facts and I'm not sure BMW even claims that but it seems to be a trend that these cars don't get these fluids changed. At least until they go on the forums.

Suffice to say I want my trans in my first Bimmer to last at least as long as my n52... Hopefully....

[mapleleaf1773]

Well the n52 will last forever. So at some point your transmission will definitely need flushed.

Another story, my wife had a 2008 Nissan pathfinder. The transmission lines in the radiator (stupid design) cracked open mixing transmission fluid in the coolant and vice versa.

Long story short, the cvt automatic gears became delaminated destroying the transmission.

Only 1 company currently makes those specific electronic transmissions. It cost me $4,300 to get another put in. 6 months later she totaled the damn thing....

[tgeho_e92]

Originally Posted by mapleleaf1773

Well the n52 will last forever. So at some point your transmission will definitely need flushed.

Another story, my wife had a 2008 Nissan pathfinder. The transmission lines in the radiator (stupid design) cracked open mixing transmission fluid in the coolant and vice versa.

Long story short, the cvt automatic gears became delaminated destroying the transmission.

Only 1 company currently makes those specific electronic transmissions. It cost me $4,300 to get another put in. 6 months later she totaled the damn thing....

Oh no. Those Nissan CVT transmissions are junk my Altima had one and the stepper motor went out Nissan just replaces the transmission for $3k-$5k making it impossible to buy OEM replacement parts to repair whatever goes wrong. In my Altima's case the transmission was worth more than the car itself. $500 scrap run....

I just didn't want to replace my fluids and screw my diff and trans on my BMW. I really really love this car and want it to last for many more spirited miles.

[Jesda]

My 2008 E93 has the GM6L45 shared with the Cadillac ATS. Drained, filled, and replaced the filter (no flush!!) at 129k. I felt an immediate improvement. I also had to reset the trans life with my Foxwell NT150 coder to get it to shift properly.

[lowrydr310]

I changed the original transmission fluid on my 325i auto at around 235K miles. An independent BMW shop advised against it claiming the same thing that it could do more harm than good. But guess what? It significantly improved my shifting and the car drives much better now, and has been fine for the past two years and 25K miles. It was only a drain and fill, not a pressurized flush.

[CTinline-six]

Shock the metal? Sounds like whoever told you that was pulling it out of their ass.

The best thing you can do is a drain and fill with new fluid, and get all of the old junk out.

The only thing I would stay away from are transmission flushes, especially a power flush, because they can loosen any crud that's caught in the valve body and cause issues. A drain and fill with the proper fluid in both the diffs and the transmission will only prolong the life of the components and the seals.

[tgeho_e92]

Originally Posted by CTinline-six

Shock the metal? Sounds like whoever told you that was pulling it out of their ass.

The best thing you can do is a drain and fill with new fluid, and get all of the old junk out.

The only thing I would stay away from are transmission flushes, especially a power flush, because they can loosen any crud that's caught in the valve body and cause issues. A drain and fill with the proper fluid in both the diffs and the transmission will only prolong the life of the components and the seals.

It wasn't necessarily "shock" I was reading that a newer fluid would cause "bite" and maybe loosen those carbon deposits and do what you say will happen with a power flush. I'm trying to cover all my bases before continuing. Thank you for your feedback!

[ryan stewart]

LOL, shock? That is a new take on the old wives tale.

The origin of "dont change fluid on old whatever" was the theory that it would leak because it would dislodge all of the old, broken down crud that was plugging a gap in a crap gasket.

Change your fluid/filter. It serves the same purpose as changing the oil in your engine. Youre getting all of the metal shavings, grit, etc out of the system and putting in a new oil that is now back to specification for what was originally put in the car. More lubrication, no water in it (so no corrosion), etc.

My dad fell for the lifetime fluid BS on his E39 and finally gave up and sold it after all of the transmission issues he had because of a blockage that formed in the valve body and damaged it.

[tgeho_e92]

Originally Posted by ryan stewart

LOL, shock? That is a new take on the old wives tale.

The origin of "dont change fluid on old whatever" was the theory that it would leak because it would dislodge all of the old, broken down crud that was plugging a gap in a crap gasket.

Change your fluid/filter. It serves the same purpose as changing the oil in your engine. Youre getting all of the metal shavings, grit, etc out of the system and putting in a new oil that is now back to specification for what was originally put in the car. More lubrication, no water in it (so no corrosion), etc.

That's why I'm asking questions. Trying to feel my way through mountains of outdated advice. That's the main reason I'm on this forum and the exact reason I made this thread. Thank you.

[ryan stewart]

FYI invest in a good fluid pump, these bastages committed so hard to the lifetime fluid BS they didnt even put a drain plug on the diff, so you have to siphon it out. A good high volume one with a nice thick flexible hose will save you some cussing.