Redneck

Some of you may remember the previous topic I started:

https://5series.net/forums/topic/118...mission-fault/

Well, the car still has problems (very subtle subtle normal driving, very noticable under higher accelerations). Took it to a new indy I found that was blown up from the coast after Katrina and never went back, lol. He's been working on bimmers for 35 years and has thousands invested in the same diagnostics the dealer has.

Found one fault, a gear monitoring fault. Slippage from 4th to 5th, or at least about 500 revs difference according to his computer. He suggests getting the GM fluid out of the ZF and replacing it with ZF Lifeguard 6. Claims the ZF's are very persnickety about thier fluids and that he's seen many of them corrected by this. Also will change the pan/filter and inspect some gaskets/seals on the valve body.

I have no clue, I am at the mercy of someone far more experienced than I.

I dont trust the dealers, they just repeat the same propaganda they're told to. How else could you possibly pull in there on one day and have the SA tell you there's lifetime fluid in the thing, pull in there a few months later and they've changed thier minds and scold you for being 20k past due for tranny service.

Will update this thread late next week after I get the transfusion in hopes this may help someone someday.

Thanks to you all for the advice as always.


john

PS- dude also tells me the 25s tranny reset does not reset all the adaptives.... who knows?!?!

JasonH

I think your mechanic is spot on. The gearbox needs the right fluid (Lifeguard 6) at the right level. A small leak or incorrect fill level could cause your problems. The fill needs to be done just right, engine running, transmission oil temperature between 30C and 50C - very easy to do incorrectly.

seanjordan

Had mine done last month and havent had a problem since. He is telling you the right thing. You should keep this mechanic

Redneck

Sean was yours doing the same thing as mine? Did it shift bad under hard acceleration?

seanjordan

Yes. It acted like it didnt know when it was suppose to shift. Then it would go into limp mode and tell me to go to the nearest dealer. I had it at the dealer a few times but they could not find anything wrong. They just kept updating the SW. I was out of the country for 10 months and had my fiance take it to a Indy shop in Tampa and he knew exactly what the issue was. He changed the fluid gave me new plugs and said I wouldnt have the issue again. I came home last week and test drove the hell out it and it shifted perfect in auto and DS. Im loving my car again. The whole 100k till trans change is not all the way correct. That is for people who dont like to live on the edge. If you run your car hard at times give it a change around every 50k and it should be good. He said something about the trans fluid getting thicker over time with the particles and it goes to limp mode to prevent it from over heating or messing up any gears. Also he cleaned the fuel line and changed the Differential fluid. I didnt have the pan changed though because he said it wasnt needed. He just cleaned the particles from the trans. He told me that it was just a way for BMW to get more money. I am testing that theory now. So I will see. Hell it only cost me $450 for everything $1100 cheaper than the dealer. I cant complain with the outcome I have seen already.

seanjordan

To respond to the 25s reset: it does help if you know how it works. It takes it back to original learning settings and if I am correct you have to drive it for 500 mi for it to learn you driving style. I would not drive it hard between those miles I would drive it some where in between. It is only a patch. The issue will come back sooner or later because of the fluid that is in the trans.

Shlooky

Very similar story here as well...except my tranny was slowly leaking fluid, my indy said it was sweating and over time lost 3 litres of fluid. the tranny takes 6 litres. So he filled it back up, put a new gasket, kept the pan, reset the adaptation and my car has been running smooth since.

But I do drive it easy, a brand new tranny does cost $7k and a rebuilt about $5k so don't want to cause any issues with it.

seanjordan

Any update Redneck on your issue