[Mr. 5]

First of all, do this at your own risk! I take no responsibility for the mistakes that you make, so be careful. This is just a guide to make it easier for you.

You will need the following:

8mm hex wrench
8mm socket wrench
10mm socket wrench
2 quarts of whatever fluid you want to use
Aprox 3 feet of tubing with ID 3/8" or a pump
A pan to catch the fluid


When changing your tranny fluid the car must be level. I used ramps for the front and then put blocks under the rear tires.



The rear was still a little low so I jacked my car up a bit more



Locate and remove the 8mm screws that hold on the trans cover. There should be 7 of them. The cover twists 90 degrees in order to remove from the bracket.



Use the 10mm socket and take off the bracket that you just twisted the cover off. It's circled by a green circle (below). Removing this bracket makes it easier to get to the fill plug.



Take the 8mm hex wrench and remove the fill plug first. Don't forget to put your pan underneath for any spillage.
Removing the fill plug first is very important. If you drain your fluid first and you can't remove the fill plug then you're screwed!
The fill plug is located in the red circle (above) and is on the right hand side of the car.

When you have the fill plug removed then place your pan underneath the drain plug and use the 8mm hex wrench once again to remove the drain plug.
The fill plugs and drain plugs are the same.



Let it drain! Take a break!


Once it's drained enough then put the plug back in and tighten it.

Now you can add the fluid of choice. I'm using Royal Purple Synchromax. I've used Royal Purple in the past and the product is unbelievable! The shifts are like cutting through butter!



Take your hose and connect it to the tip of the fluid container. Put the other end into the fill hole and just squirt away. If you have a pump then just pump it in.



Once the fluid starts to overflow, you are done filling it up.
Our cars take just under 2 quarts.

Put the fill plug back in and torque it down.
Wipe off the excess fluid and start your car.
Make sure there are no leaks!
Put everything back, put your car on the ground and drive the heck out of it!

[Park2670]

This is a really stupid question, but why did you change your fluid? Just for the decreased shift effort? Or are there other benefits of not having the Stock fluid in?

[Mr. 5]

Originally Posted by Park2670

This is a really stupid question, but why did you change your fluid? Just for the decreased shift effort? Or are there other benefits of not having the Stock fluid in?

I didn't like the way the gates felt.
Sometomes when I was shifting from 2nd to 3rd, it felt like I was hitting a barrier and I had to press harder than normal.
After driving with the Synchromax, the shifting is a lot smoother!

[533ogetnom]

is it really a lot smoother or a placebo?

nice to see this though because i was thinking about doing this after grinding the crap out of 4th gear at the track a few weeks back, but i didnt feel putting it up, crawling under there, poking around, trying to figure out what size tool i need, cursing because i didnt have one, taking it down going and buying tools putting it back up, cursing because im still missing one and now out of tranny fluid... ect lol

[Mr. 5]

Originally Posted by 533ogetnom

is it really a lot smoother or a placebo?

I'll tell you after a week of driving.
But it felt really good today.

[BMW2Hart]

Great DIY!

How many miles to you have on your car?

I am close to 50K miles and plan on changing the fluids in the trans and diff

at that time.

[NavyBusa]

Thanks for posting. I've been thinking about doing mine for awhile but haven't had a chance to crawl under the car and figure it out. I always change the transmission and rear end oil with quality synthetics. Most people don't realize how transmissions and differentials break-in just like the engine and can create substantial amounts of metallic contamination.

[txusa03]

As always, your DIY are very informative. What is tubing with ID 3/8", more precisely what is ID and where I can find this tubing?

Also, stating that "The fill plugs and drain plugs are the same." can be misleading. There are two physical plugs with the same size correct?

Anyway, I thought someone mentioned that the trans fluid was lifetime and cannot be removed. Now I know to only listen to Mr. 5

My car is 50K now and I contemplate on doing this but I only have one car so if I screw up, I am really screw ...

[ttdmac]

Are there any torque specs for the 8mm Hex bolt for both fill and drain plugs?

[piezo]

Originally Posted by ttdmac

Are there any torque specs for the 8mm Hex bolt for both fill and drain plugs?

The 07/2006 TIS DVD I came across gives 35 Nm, but you may want to confirm with a pro:

http://www.e90post.com/forums/showthread.php?t=112294

[xspeedy]

A couple of points I learned from a local indy shop owner:

If you use a quart bottle like what Redline comes in, you can make your own pump. Don't waste your time with those cheap siphon pumps that work poorly.

Drilling doesn't work so well, so I melted a hole in the cap that allows the clear plastic tubing (found at your local auto parts store) to fit tightly. I just found an old drill bit that was slightly smaller that what I needed and heated the shank with a torch. Then I applied the heated end to the cap (screwed onto an empty bottle) and worked it around until I had the hose size I needed. Pushed the tubing down to the bottom of the bottle and stuck the other end up into the fill hole of the gearbox or diff. Squeeze while holding the bottle upright.

To prevent leaks from the plugs, apply some thread sealant to them. This typically comes in paste and tape form. I have heard that the paste is better. Apply to the threads near the head of the drain plug before installation.

[lauer87]

Anyone know how much different, if at all, XI manuals would be to do?

[noire07]

Originally Posted by lauer87

Anyone know how much different, if at all, XI manuals would be to do?

It's exactly the same.

[CK]

The foreman in my dealership told me not to change the fluid. The transmission warranty will be void if you change the fluid.

[pwrpuma]

Hey Yall,

This is an EXCELLENT post on DIY transmission fluid changes for the e90 BMW frame! I had the transmission fluid changed with the Royal Purple Synchromax on my 6MT car and the results were instantaneous. The shifts are smoother than the past, and the transition from the gears is more predictable (due to the fresh oil). I highly recommend this task on all yall's car.

I can see on an auto tranny how the transmission fluid can last for 100K miles, but for those of us with the 6MT, this is highly unlikely, since we go through the gears differently, especially in high traffic areas.

This is one of the best posts I've seen on this forum!

-puma

[voltron1011]

subscribed..

[chaz58]

Good post.

A couple of observations:
- for a 328, I used a funnel and about 3ft of plastic tubing to pour in the trans fluid. Took just under 2 bottles of redline MTL. Round the tube down by the exhaust (your CATS must be cold for this!)
- If I had seen this earlier I would have known the correct torque. I overtorqued the drain plug and the material around the hex nut began to crack. At least the threads are OK! Not a big deal - $11 at the dealer for a new plug, but I have to wait a couple of days to drive again.

Thanks for the writeup!

[chaz58]

Oh yeah - good point about warranty. I'm going to put the stock stuff back in if I have to take it to the dealer for trans repairs. Certainly something like Redline or Royal Purple isn't going to hurt your transmission though. This is probably a good maintenance task to do every 30,000 miles if you plan on keeping your car.

[CHARLEYBROWN]

JUST did this in my e90 330i and it was well worth it! LOVE the royal purple! I felt smoother more precise shifts instantly!

[jimk]

This is what I got from red line when I was inquiring about the tranny, differential and transfer case fluids:

Jim,

Thank you for contacting Red Line Oil, in your manual transmission I would recommend the D4ATF, the X-Drive transfer case calls for a special fluid which we don't offer a cross for at this time and 75W90 in the differentials.

Regards, Dave
Red Line Oil

[AlanAZ]

Thanks for the info Jim. And that seals it for me - I'd rather not do auto transmission fluid in my manual gearbox, and will be going with Synchromax. Time to order it and new bushings for the gearshift linkage.

[voltron1011]

Originally Posted by AlanAZ

I intend to replace my gearbox fuild with Redline MTL (based on previous good experience with it) soon, but since I live in the Phoenix area, I'm considering using MTL90 to cope with the extreme heat here.

Anyone have experience or thoughts on this? Thanks.

According to Turnermotorsport.com, BMW manual transmissions require ATF D4 (yes Automatic Transmission). I've also read elsewhere that BMW has recommended D4 for all of their manual transmissions since '96.