How to add transmission fluid to bmw 328i

Applicable Models:

• Project Time: 3 hours
• Tab: $
• Talent
• Tools: Fluid pump, 17mm wrench

• Parts Required: Automatic transmission fluid. Filter and gasket kit.
• Performance Gain: Extend lifetime of your transmission
• Complementary Modification: Change engine oil at same time

The automatic transmission fluid is normally filled with lifetime fluid.

BMW defines lifetime as 100,000 miles. Therefore, it is a good idea to service your fluid every 50,000 miles. If you're unsure of the last service, replace the fluid as soon as possible. Doing so will extend the life of your transmission. There are many options for replacement fluid. Choose the best you can afford and be sure it meets BMW's current specifications for your vehicle. To determine the fluid that belongs in your transmission, check your owners manual, or give our parts specialists a call. You have two options when replacing, you can drain and fill the fluid, or you can drain the fluid and replace the fluid strainer by dropping the transmission fluid pan. For the first service, I usually drain and fill only, then the next one I would replace strainer. Replacing the strainer allows you to clean transmission fluid pan of dirt and debris. One all-wheel drive models, a metal oil pan is utilized, allowing the strainer to be serviced separately. Rear wheel drive models utilize a plastic oil pan with a built in strainer. To service the strainer, you will have to replace the oil pan.

In this tech article, I will go over how to replace the strainer and drain and fill your transmission fluid. The vehicle shown in this photo is a 2009 E90 with a GA6L45R transmission. Other automatic transmissions used in E90 models are similar and this procedure should help you get the fluid replaced without a problem.

Drive vehicle for about 3 miles to warm transmission fluid.

Jack up all four corners of your vehicle. I suggest using four jack stands and slowly raising vehicle to required height. See our Tech Article on How to Jack Up Your BMW. Vehicle needs to be level when checking and replacing fluid.

Check out our complete Technical Article Directory for guides to many other procedures. 

Check out our Basic Maintenance section, which has all the parts you'll need to get your vehicle running its best, including filters, fluids, brakes, spark plugs, lighting, and more for your E90! 

Hot tip

Work on hard level surface.

//

Project Photos

Figure 1 Place drain pan under your transmission and remove 6mm Allen fluid drain plug. (green arrow) Allow the fluid to drain completely. Do not discard fluid, you will have to measure the amount that came out of transmission later. This will help with refilling the transmission with the correct amount of fluid. If you are only draining and filling the fluid, skip the next step. You will not have to remove the transmission oil pan.

Figure 2 Once fluid is completely drained. Remove transmission pan mounting fasteners, there are seventeen 10mm fasteners. (green arrow points to dotted area of fasteners). Before loosening these fasteners, clean all dirt and debris from around transmission pan. Then remove transmission pan from transmission. Pull old gasket off transmission and discard.

Figure 3 This diagram shows the components involved in a transmission fluid service on an all-wheel drive model. To remove the strainer, pull strainer down, be sure strainer O-ring comes out with strainer. If not, remove O-ring from transmission. Rear wheel drive models utilizr a plastic oil pan, the strainer is built into the pan. You will be replacing the entire pan. Install new strainer in reverse order of removal. Then install transmission fluid pan and tighten fasteners. The gasket has two plastic tabs that snap into the transmission pan to secure it in place during tightening. Be sure to align these plastic tabs correctly. Continue here if only performing a drain and fill Measure amount of fluid drained that you previously drained from your transmission.

Figure 4 Remove 16mm fill plug, green arrow point to fill plug location. Fill transmission with same amount of fluid that was drained from it. This photo shows the fill plug on a GA6L45R transmission. On other models the fill plug is located on the side of the transmission. Start engine, then apply parking brake, hold your foot on brake pedal and shift transmission through all gears. This with circulate transmission fluid. Place transmission selector in Park, then remove fluid fill plug. Monitor transmission as it reaches a temperature of 100° F. You can check this with an infrared temperature gauge. If a small stream of fluid runs out of fill plug, fluid level is correct. If no fluid runs out, add oil until it starts to run out. Reinstall fill plug and tighten once complete. I suggest driving car, then allowing it to cool and rechecking fluid level. Now here's a tip, once you have filled the transmission with the same amount of fluid drained the level should be close to what it was. Start engine, move gear selector as noted above. With the transmission fluid still cold and fluid fill plug removed, monitor the temperature and fluid flow at fill plug. When the fluid warms up it will expand and should run out of fill plug, if it does not, add fluid until it starts to run out. Install fill plug and repeat once vehicle is cool. Check fluid temperature using a temp gun. 30: 50°C (86: 122°F) Aim for the center of the transmission pan then check temperature this way. The ideal way is to check fluid temp using a BMW scan tool, but not all of us have access to one. Place transmission in Park. Remove fill plug. A small amount of fluid should stream out of fill hole. This indicates the level is correct. If it doesn't stream out, fill fluid until it does. Once you reach desired capacity, drive vehicle and repeat level checking procedure.

How do you fill transmission fluid in a BMW?

Where is the transmission fluid located on a BMW 328i?

How do I know if my BMW is low on transmission fluid?

What kind of transmission fluid does a BMW 328i take?