Hi folks,
I have a 2009 BMW 135i manual 6 speed and want to change out the rubbish "lifetime fill" in the transmission and diff.
However, I'm getting conflicting information from all over the place, so am utterly confused.
A lot of the advice I read is to use Redline products (probably because they're highly revered in the BMW world), however nobody seems to agree on exactly which product to use.
I believe that my trans comes with an ATF as standard, and Redline themselves recommend their D6 ATF, as it most closely matches the BMW specs.
However, my oil dealer recommended I use the Redline MTL fluid, which is thicker, and as I understand, lubricates better. I mentioned that cold weather shifting was pretty important to me, and was then recommended to mix Redline D4 ATF with the MTL for the best of both worlds.
I've also seen elsewhere that running just MTL is apparently what gearbox builders have been recommending and what they've been filling the gearboxes with after rebuilding.
There seem to be anecdotal accounts of MTL, D4, and D6 all being used, but I just really want to know which is best. I read an article by Mike Miller (supposedly a BMW guru of sorts?) stating that ATFs aren't really very good at lubricating bearings. He said that he'd always use MTL unless he couldn't trust the driver to shift proerply in cold weather, in which case he'd use the D4.
My car currently has approx 38,000 miles on the clock and shifts OK, though could be better betwen 1st-2nd and sometimes requires me to lift and re-depress the clutch to get into first, although this only happens occasionally. I understand that some have experienced this from new on more BMWs, so I think it's just a gearbox trait.
I'm also in the UK where it can get to around -10 centigrade in winter sometimes, but mostly sits around 0 - 5 degrees through winter and winters seem to be lasting longer and longer these days! Today it's supposed to get up to 20 degrees though (still centigrade) so it's not the coldest place around - probably similar temps to New York, I suppose.
My daily journeys see the car warming up just by the end of the journey (about 15 miles each way) so it spends most of its time cold or cold-ish, however, I don't want to just plump for an ATF for the cold shifting qualities if it doesn't have great lubrication for the bearings, so based on the above, what would be the best fluid for my car's transmission? Or what would you recommend?
Thanks in advance for any help you can offer.
Russ
I have a 2009 BMW 135i manual 6 speed and want to change out the rubbish "lifetime fill" in the transmission and diff.
However, I'm getting conflicting information from all over the place, so am utterly confused.
A lot of the advice I read is to use Redline products (probably because they're highly revered in the BMW world), however nobody seems to agree on exactly which product to use.
I believe that my trans comes with an ATF as standard, and Redline themselves recommend their D6 ATF, as it most closely matches the BMW specs.
However, my oil dealer recommended I use the Redline MTL fluid, which is thicker, and as I understand, lubricates better. I mentioned that cold weather shifting was pretty important to me, and was then recommended to mix Redline D4 ATF with the MTL for the best of both worlds.
I've also seen elsewhere that running just MTL is apparently what gearbox builders have been recommending and what they've been filling the gearboxes with after rebuilding.
There seem to be anecdotal accounts of MTL, D4, and D6 all being used, but I just really want to know which is best. I read an article by Mike Miller (supposedly a BMW guru of sorts?) stating that ATFs aren't really very good at lubricating bearings. He said that he'd always use MTL unless he couldn't trust the driver to shift proerply in cold weather, in which case he'd use the D4.
My car currently has approx 38,000 miles on the clock and shifts OK, though could be better betwen 1st-2nd and sometimes requires me to lift and re-depress the clutch to get into first, although this only happens occasionally. I understand that some have experienced this from new on more BMWs, so I think it's just a gearbox trait.
I'm also in the UK where it can get to around -10 centigrade in winter sometimes, but mostly sits around 0 - 5 degrees through winter and winters seem to be lasting longer and longer these days! Today it's supposed to get up to 20 degrees though (still centigrade) so it's not the coldest place around - probably similar temps to New York, I suppose.
My daily journeys see the car warming up just by the end of the journey (about 15 miles each way) so it spends most of its time cold or cold-ish, however, I don't want to just plump for an ATF for the cold shifting qualities if it doesn't have great lubrication for the bearings, so based on the above, what would be the best fluid for my car's transmission? Or what would you recommend?
Thanks in advance for any help you can offer.
Russ
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