The entire advantage the BMW xDrive models have over the others is the significantly improved grip they have in treacherous conditions. Where the rear-wheel-drive models struggle in the snow, the xDrive-equipped cars can charge ahead in a safe and controlled manner. To drive the front wheels, BMW adds a transfer case to send the power to the front and a front differential to distribute it to the wheels. Inside the differential is a ring and pinion gear set, and just like everything else involving gears, it needs a lubricating fluid.
We recommend only using the OE BMW G2 Hypoid gear fluid. You are welcome to try other gear fluids, but we can't speak to their effectiveness in mitigating wear on the gears inside your differential. Once you have your fluid of choice, the fluid change is a very straightforward process. You should have no trouble with this job, even with minimal experience, as long as you follow the steps below.
BMW models and years applicable:
This DIY applies to numerous BMWs extending further than just the F30. The DIY includes the 2-series xDrive models, 3-series xDrive, and 4-series xDrive.
What type of fluid is used in the BMW F30 front differential?
The BMW F30 requires particular fluid for the differentials. It's recommended to only use BMW's G2 Hypoid Differential Fluid, and we stand behind that. You can find the G2 fluid here:
How much will it cost to replace BMW F30 front differential fluid?
All you need to complete the change is two new drain plugs and a couple of bottles of fluid. According to BMW, although the drain and fill plugs are metal, the Viton-style seal they use is a one-time-use. The two new plugs will run you just over $10 for the pair.
BMW sells 500ml bottles of fluid, and the differential takes roughly 700-800ml. The bottles are around $54 a piece, so you'll need around $100 in the fluid to fill the diff. Altogether, budget around $130 for the job. The extra money is best put towards some brake clean or rags to clean the excess fluid that will spill out of the diff.
How long will it take to replace BMW F30 front differential fluid?
Replacing the fluid shouldn't take you long at all. Once you remove the twenty-something fasteners from both underbody panels, you can directly access the fill and drain plugs. Put aside half an hour to forty-five minutes to complete the job in your driveway.
Parts required to replace BMW F30 front differential fluid:
Tools required to replace BMW F30 front differential fluid:
- CTA Extraction Pump
- 8mm Socket
- 10mm Socket
- 14mm Hex Bit Socket
- ½" Breaker Bar
- ½" Extension
- Torque Wrench
Steps required to replace BMW F30 front differential fluid:
Step 1: Remove the underbody panels
Jack up the front of the car and place it onto jack stands. Then slide under the car with an 8mm and 10mm socket, and remove the two underbody panels. Start with the rear panel covering the transmission. Then, remove the forward panel under the engine.
Step 2: Replace the fluid
Before draining anything, remove the fill plug. We do this so that we know we can refill the diff once we drain it. If the fill plug refuses to come out, don't drain the fluid.
The fill plug sits behind the driver's side axle. Use a 14mm hex bit socket to remove it from the differential housing.
Then, use the same socket to remove the drain plug from the differential. The fill plug is accessible through a hole in the reinforcement plate. Have a drain pan positioned under the plug to catch the fluid.
Let the oil drain out and then fit the new drain plug. Torque the plug to 60Nm with the 14mm hex bit socket.
Next, use the syringe to pull the fluid from the bottles and fill the differential. The diff holds just under one liter, so you'll use nearly all of two bottles. You'll know it is full when fluid runs out of the fill plug hole.
Clean up the excess fluid from the diff and thread in its new plug. Like the drain plug, torque the plug to 60Nm with the 14mm hex bit socket.
Step 3: Refit the underbody panels
Start by fitting the forward panel under the engine. Use an 8mm socket to tighten the many fasteners that hold it up. Then, refit the rear panel. All but one of the fasteners requires an 8mm socket, the lone other needing a 10mm.
Lastly, jack the car up, take it off the jack stands, and lower it back down.
BMW F30 Front Differential Torque Specs:
- BMW Front Differential Fill & Drain Plugs = 60Nm or 44.3 ft-lbs, of torque
Replacing the fluid is the best way to extend the life of your drivetrain components without spending an arm and a leg on new parts. If you're interested in more DIYs for your BMW, you can visit bmw.fcpeuro.com and subscribe to our YouTube channel.