Test drive after changing gear box fluid?

[m3f_Bmwpower603]

I was wondering if anyone knew if it is best to test drive immediately following a manual gear box fluid change.







Here's a pic of The new pump I used to pump in new fluid with. $50.00 from bav auto



I had to put the D4 in another container because the end of the hose wouldn't fit in the bottle!

[m3f_englishtom1596q]

could have bought a $5 pump from harbor freight but a $50 one works ok too. As for driving it after service, it doesn't matter, its not like an auto where fluid has to go through a filter, pump, actuators etc.

[m3f_deboM3]

Technically you dont need to drive after the oil change, but I always test drive after I do anything, just to make sure everything is all good. Last thing you want is to find an issue when you need to get somewhere or whatever.

[m3f_Bmwpower603]

could have bought a $5 pump from harbor freight but a $50 one works ok too. As for driving it after service, it doesn't matter, its not like an auto where fluid has to go through a filter, pump, actuators etc.

Thank you for the reply.



I am glad I didn't purchase this for a transmission job on an automatic. I think when I do my 540iA. When that time comes I'll look for a universal pump made for the typical size bottles.



The pump I used would only hold about .5 of a liter, until it lost suction to be able hold any more.

[m3f_Earthwormjlm]

I let my car idle in neutral for a couple minutes, but I doubt that really matters.


There should be no difference between letting the car sit overnight, and flushing the transmission fluid. Where do you think the fluid naturally goes when the car isn't being used? To the bottom of the transmission.

[m3f_Bmwpower603]

I let my car idle in neutral for a couple minutes, but I doubt that really matters.


There should be no difference between letting the car sit overnight, and flushing the transmission fluid. Where do you think the fluid naturally goes when the car isn't being used? To the bottom of the transmission.

Took it for a test drive today. I refused to yesterday due to the rainy weather. Shifting feels more smooth, clutch feels to engage nicely also. The only thing I did notice which was a small problem before. Is the shifter seems to not be centered. When I'm in nuetral and want to go to third gear. Sometimes it goes into 5th gear! Here's a pic to show you how the shifter is positioned a little more to the right.

[m3f_englishtom1596q]

The infamous 5th gear lean

[m3f_thirtysixnick]

The infamous 5th gear lean

Something most of us deal with, and to some of us it's our downfall.

[m3f_Double E]

Somewhat-related scenario and question...



In our E36 (race car, non-M with stock Getrag), instead of ATF, my teammates swear by using manual trans gear oil in there and adding in a bottle of STP oil treatment.



In an in-home test, they heated up a few ounces of ATF to 250, a few ounces of manual trans gear oil to 250 and a few ounces of gear oil with STP in it to 250. That was enough for them to change when only the combination of STP & gear oil did not appear to have the viscosity of water.



The side of the trans case has the specification for ATF, same as the ZF trans in the M3. Can you think of any negative result of using the gear oil mix?

[m3f_Earthwormjlm]

Somewhat-related scenario and question...


In our E36 (race car, non-M with stock Getrag), instead of ATF, my teammates swear by using manual trans gear oil in there and adding in a bottle of STP oil treatment.


In an in-home test, they heated up a few ounces of ATF to 250, a few ounces of manual trans gear oil to 250 and a few ounces of gear oil with STP in it to 250. That was enough for them to change when only the combination of STP & gear oil did not appear to have the viscosity of water.


The side of the trans case has the specification for ATF, same as the ZF trans in the M3. Can you think of any negative result of using the gear oil mix?

ATF is thinner, so it leads to smoother feeling gear shifts. Transmission temperatures don't get too high on a regular street car, so ATF is fine for the temperature ranges the transmission will see.


Race cars will see way higher temperature ranges, so MTF isn't a bad idea. If you see mixes, it's often ATF+MTF, to get some smoothness back.


Isn't MTF basically the same stuff as gear oil, just with some more additives in it?

[m3f_Double E]

Thumbs up. Thanks!