Manual Trans Fluid

[richbarn2]

I have been reading numerous threads regarding manual trans fluids. I just changed my LSD fluid out with Swepco 201. I would like to stay with swepco, I was considering their hyd fluid, 714 as it replaces dexron. Any comments?

I believe it is available in 10wt and 20wt, I live in PA.

[DesktopDave]

Dexron is approved for BMW manuals.  I'd guess that either would work, I'm told that ATF is generally 5 to 15wt.  I've used it in several fork rebuilds instead of 15w fork oil to lower harshness.

I'd assume it'd work, but I wouldn't be the guinea pig...  I've used gear oil & ATF...both have worked well.

[richbarn2]

I was considering using the swepco 201 gear oil in my trans (because I bought a gallon) but was concerned with the viscosity.

Being a fellow PA resident, how did the gearbox feel in the winter with gear oil? I can deal with stiff shifts until it warms up.

This is my first BMW and its the first manual trans I have owned that requires ATF.?.

[Chalino]

I was considering using the swepco 201 gear oil in my trans (because I bought a gallon) but was concerned with the viscosity.

Being a fellow PA resident, how did the gearbox feel in the winter with gear oil? I can deal with stiff shifts until it warms up.

This is my first BMW and its the first manual trans I have owned that requires ATF.?.

I had gear oil in my 240 for about a week. Shifts were too notchy and the drivetrain seemed quite a bit sluggish due to the gear oil weight 80-90W. I'm back to using good ol' ATF and it feels much better. If Swepco 201 is a ATF substitute, I don't see why it wouldn't work.

[DesktopDave]

I replaced the stock ATF with gear oil in tranny & diff.  They're not that different in shift feel, even gear oil is a lot thicker than ATF.  I do have to take it easy on the transmission for the first 1/2 mile or so, otherwise I beat the syncros to the shift.

Synthetics made a big difference for me, especially in our cold start shifting.  I think next time I'll be going with a full synthetic ATF except for my LSD diffs.

That reminds me of a question...has anyone used Royal Purple?  I was wondering if it was worth the price.  I think it's a full PAO class IV synthetic, and it's commonly available around here.  I'd switch if I could verify that.  There is a lot of opinion floating around about it currently.

[Chalino]

I replaced the stock ATF with gear oil in tranny & diff.  They're not that different in shift feel, even gear oil is a lot thicker than ATF.  I do have to take it easy on the transmission for the first 1/2 mile or so, otherwise I beat the syncros to the shift.

Synthetics made a big difference for me, especially in our cold start shifting.  I think next time I'll be going with a full synthetic ATF except for my LSD diffs.

That reminds me of a question...has anyone used Royal Purple?  I was wondering if it was worth the price.  I think it's a full PAO class IV synthetic, and it's commonly available around here.  I'd switch if I could verify that.  There is a lot of opinion floating around about it currently.

You didin't feel a drag on the drivetrain? As if the e-brake has engaged? Mine did and that's why I chose to go back to ATF....

[DesktopDave]

Not anything unusual.  In fact, my mileage increased dramatically by about 2mpg highway.  I'll bet the lower viscosity of the ATF would further improve mileage.

It's the original 240 tranny with 270k miles (I'd imagine it's broken in).  While I'm bragging about mileage, the 3.73 diff also helped, so I'm up about 3-4mpg over baseline over the summer.  I have yet to take some long trips with the cruise control...we'll see what that does for my mileage.

Granted, there are many variables so it's really just a guess.  Winter mix fuel or >5% alcohol mix really hurt my mileage.