gojozoom 6 Report post Posted September 3, 2020 (edited) Hi guys, I thought I'd share my little journey with my faulty GM auto transmission (in my 2007 BMW 130i LCI) so that anyone having similar issues might take away something from it. The symptoms: a "phasing" vibration at lower RPM (below 2000) under load (uphill). It's to do with the torque converter delamination. There are 3 stages to fixing it: 1) Glycol test to make sure the sealants and gaskets are fine and there is no water or antifreeze in your oil - this only costs only $100, so it's totally worth it. If you skip this and just go for a full service/rebuild your trans issues can come back in a year, as the electronic and mechanic components will keep getting corroded by water. I'm getting this done today - I hope it comes back "negative". 2) Full transmission service (oil change, filter, and optionally anti-shudder additive). These GMs need this done every 80K kms or so, but most people don't even think about trans service when it comes to general maintenance. Mine has 127K in it and I'm sure it's never been done. In most cases this will sort out the vibration and the additive will create a nice protective layer on the components. This costs around $500. 3) Torque converter rebuild - well, obviously this is the most expensive, starting around $1500 but can easily end up in the upper 2K range. Luckily I still have warranty from the dealer and I also have 2 years mechanical warranty from Autosure, but still, fingers crossed that it won't come to that. I'll see how the glycol test goes today and I'll update this post as I go. As a side-note , as much as I love European cars, I've always had issues with auto transmissions (except my MK5 GTI I had was manual). I had an Audi A3 - mechatronic failed, then a Golf 1.4 TSI with the infamous DQ200 DSG - mechatronic and clutch pack failure, and now this. I'm pretty sure Autosure hates me now - they paid out about 7K in the last 3 years Cheers Dan Edited September 3, 2020 by gojozoom 2 Quote Share this post Link to post Share on other sites
Driftit 2093 Report post Posted September 4, 2020 Hah. Just done all that. Service and additive solved it 100% for me. Only took a few hours. Mine was low on oil and had been done before. I feel this made the issue worse. Likely someone didn't fill it correctly. Quote Share this post Link to post Share on other sites
///M 22 Report post Posted September 4, 2020 1 hour ago, Driftit said: Hah. Just done all that. Service and additive solved it 100% for me. Only took a few hours. Mine was low on oil and had been done before. I feel this made the issue worse. Likely someone didn't fill it correctly. Is it worth adding the anti-shudder fix when doing the fluids and filters? I don't have the shudder but need to change the transmission fluoid ASAP (over 130,000km) Quote Share this post Link to post Share on other sites
gojozoom 6 Report post Posted September 4, 2020 That's good news, thanks for confirming that. Fingers crossed. Quote Share this post Link to post Share on other sites
Driftit 2093 Report post Posted September 4, 2020 13 minutes ago, ///M said: Is it worth adding the anti-shudder fix when doing the fluids and filters? I don't have the shudder but need to change the transmission fluoid ASAP (over 130,000km) It's only $15 from Repco. It's the most common solution for the box in other brands that have the same box. 1 Quote Share this post Link to post Share on other sites
gojozoom 6 Report post Posted September 11, 2020 Well, they found glycol in the oil so this is gonna be a swap or a rebuild. That explains why this otherwise mint car was traded in... The dealer is setting things up, I'll update this thread as I go... Quote Share this post Link to post Share on other sites
M3AN 4016 Report post Posted September 11, 2020 (edited) That sucks, great you have warranty coverage. How does glycol, presumably from your coolant, actually get into the transmission? Edited September 11, 2020 by M3AN Quote Share this post Link to post Share on other sites
aja540i 1906 Report post Posted September 11, 2020 Leaky cooler? Quote Share this post Link to post Share on other sites
M3AN 4016 Report post Posted September 11, 2020 3 hours ago, aja540i said: Leaky cooler? Do modern cars use the engine coolant to also cool the trans? This may be my ignorance of modern vehicles but the only platform I know well enough is the e36 and there was no relationship between the engine coolant and the transmission back then. The auto cooler was a separate radiator up front that you pumped your transmission fluid through. Quote Share this post Link to post Share on other sites
KwS 2429 Report post Posted September 11, 2020 They generally have a tube that runs inside the radiator tank to heat/cool the trans fluid. This is common for failing and mixing fluids. In the case of the 130i it appears they have a heat exchanger mounted to the radiator and acts as its own little radiator with coolant and trans fluid flowing through it. I guess the internals of this heat exchanger must have failed. 1 Quote Share this post Link to post Share on other sites
aja540i 1906 Report post Posted September 11, 2020 8 hours ago, M3AN said: Do modern cars use the engine coolant to also cool the trans? This may be my ignorance of modern vehicles but the only platform I know well enough is the e36 and there was no relationship between the engine coolant and the transmission back then. The auto cooler was a separate radiator up front that you pumped your transmission fluid through. I like how you consider 2007 to be a "modern car" ! 1 1 Quote Share this post Link to post Share on other sites
Driftit 2093 Report post Posted September 13, 2020 Heat exchanger failing? First I have ever heard of that on a BMW. Quote Share this post Link to post Share on other sites
B.M.W Ltd 950 Report post Posted September 13, 2020 1 hour ago, Driftit said: Heat exchanger failing? First I have ever heard of that on a BMW. Had this happen a few times Quote Share this post Link to post Share on other sites
Driftit 2093 Report post Posted September 13, 2020 12 minutes ago, B.M.W Ltd said: Had this happen a few times Can't be that coomon though right Glenn. I would expect you to have seen it though. Quote Share this post Link to post Share on other sites
gojozoom 6 Report post Posted September 14, 2020 Still waiting for an update from the dealer but your comments make me think if a full service + heat exchanger replacement would sort this out? Quote Share this post Link to post Share on other sites
B.M.W Ltd 950 Report post Posted September 14, 2020 (edited) Water/Glycol in a transmission usually always ends up terminal https://www.mistertransmission.com/water-in-the-transmission/ Edited September 14, 2020 by B.M.W Ltd 1 Quote Share this post Link to post Share on other sites
gojozoom 6 Report post Posted March 4, 2021 Quick update on this; after months of waiting and liaising with the dealer the trans has been replaced and the torque-converter rebuilt... Thank god for the warranty - ended up around $4600... The culprit (as discussed before) that silly oil cooler that fails and lets water into the trans which corrodes everything... Kinda silly design if you ask me as the trans itself is pretty much bulletproof. 1 Quote Share this post Link to post Share on other sites
Kiwi_BMW 89 Report post Posted March 5, 2021 Glad you got it sorted, but September to March seems a fairly long time to have this done, what was the hold-up? BTW for those using shudder fix, it is a zinc additive, which eventually fails to work as the actual problem eventually gets that bad shudder fix becomes ineffective. Usually by that stage the only fix is to rebuild the transmission. Quote Share this post Link to post Share on other sites
gojozoom 6 Report post Posted March 7, 2021 The holidays slowed things down + delay with coming to an agreement with the dealer + the transmission guy having a long line of cars to fix before mine = 5 months Quote Share this post Link to post Share on other sites