Hello everyone.
My father has a BMW 330XD with a GM transmission, the A5S390R.
For what I know, this transmission has proven to be reliable in petrol BMW and in some Cadillac and other GM vehicles, but, when mounted in 6 cylinder BMWdiesel, it's been really bad.
BMW did an awful election with this transmission, as the 390 means the maximum torque that the transmission can hold up with, so 390NM, while the 330XD has a 410NM max torque.
The same applies with many BMW 530d, and, specially X3 and X5 models.
In Spain, the list of owners of these vehicles with transmission failure is huge, specially dramatic the number of cases in the X5, X3 and 330XD cases (it's rare when they got past 150.000 km / 100.000 miles without breaking the transmisssion), the X means permanent 4x4, so it seems it doesn't help.
It also doesn't help that BMW, at least in Spain, doesn't include the fluid change in their maintenance programs and it's advertised as a lifetime fluid.
In my father's case, the transmission said it had been enough with 100.000 km / 70.000 miles, and had to have it rebuilt.
Now it has 160.000 km and it's time for a fluid change. I was thinking into moving up to Dexron VI (the specified fluid from BMW is Dexron III). The BMW guys said: no way!!, you can only put Dexron III fluid as it's what it's been designed for. If you want to put a better quality fluid, put a fully synthetic Dexron III, but never Dexron VI.
I don't trust them much as you can imagine, so I didn't even bother to explain them the downwards compatibility of Dexron VI with the previous fluids.
Anyway, even though I'm leaning into using Dexron VI, I'd like to ask your opinion and ask if you recommend a particular brand or any other alternative for this transmsission.
Thank you.
My father has a BMW 330XD with a GM transmission, the A5S390R.
For what I know, this transmission has proven to be reliable in petrol BMW and in some Cadillac and other GM vehicles, but, when mounted in 6 cylinder BMWdiesel, it's been really bad.
BMW did an awful election with this transmission, as the 390 means the maximum torque that the transmission can hold up with, so 390NM, while the 330XD has a 410NM max torque.
The same applies with many BMW 530d, and, specially X3 and X5 models.
In Spain, the list of owners of these vehicles with transmission failure is huge, specially dramatic the number of cases in the X5, X3 and 330XD cases (it's rare when they got past 150.000 km / 100.000 miles without breaking the transmisssion), the X means permanent 4x4, so it seems it doesn't help.
It also doesn't help that BMW, at least in Spain, doesn't include the fluid change in their maintenance programs and it's advertised as a lifetime fluid.
In my father's case, the transmission said it had been enough with 100.000 km / 70.000 miles, and had to have it rebuilt.
Now it has 160.000 km and it's time for a fluid change. I was thinking into moving up to Dexron VI (the specified fluid from BMW is Dexron III). The BMW guys said: no way!!, you can only put Dexron III fluid as it's what it's been designed for. If you want to put a better quality fluid, put a fully synthetic Dexron III, but never Dexron VI.
I don't trust them much as you can imagine, so I didn't even bother to explain them the downwards compatibility of Dexron VI with the previous fluids.
Anyway, even though I'm leaning into using Dexron VI, I'd like to ask your opinion and ask if you recommend a particular brand or any other alternative for this transmsission.
Thank you.
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