Transfer case repair kit for one oil drain plug for BMW ATC35L

Special tool kit for retrofitting an oil drain plug to the ATC35L transfer cases from BMW with xDrive, all-wheel drive.

On many BMW models of the F series with xDrive all-wheel drive, the transfer cases fail prematurely.

The main types of damage occur due to the following causes:

• Transfer case damage due to oil wear caused by aging
• Transfer case problems due to abrasion of the clutch linings
• Transfer case damage due to oil oxidation caused by moisture

BMW specifies a lifetime fill for these transfer cases – an oil drain plug is NOT provided. Each change of the transfer case oil requires removal of the complete unit.

Problem solution: We have designed a mounting bracket with drill bushing that serves as a template. This determines the exact position and depth of the bore to be made. The included drilling and milling tool is manufactured with high complexity and creates the bore in the housing. At the same time, it mills a flat sealing surface for the later sealing ring of the oil drain plug and produces an internal chamfer as a “starting aid” for the tap. Filling is possible via a filler screw further up, using a hook filling adapter and hand pump.

Procedure:

1. Bolt the template holder to the transfer case
2. Screw in the drill guide up to the stop
3. Drill through the housing with the drilling and milling tool
4. Allow the oil to drain completely
5. Coat the tap with grease and cut the thread into the bore
6. Flush the transfer case with fresh oil to remove any possible chips and deposits
7. Screw in the sealing plug and tighten it with 10 - 15 Nm

Suitable for the following rear axle transfer cases: ATC35L 27105A371F3, 27105A4A093, 27108612557, 27108643150

Suitable for the following vehicles:

• 1 Series: F20, F21
• 2 Series: F22, F23
• 3 Series: F30, F31, F34, F35
• 4 Series: F32, F33, F36
• 5 Series: F07, F10, F11, F18
• 6 Series: F06, F12, F13
• 7 Series: F01, F02
• X1 Series: E84
• X3 Series: F25
• X4 Series: F26
• X5 Series: F15, F85
• X6 Series: F16, F86

Original numbers are for comparison purposes only, this is not an original tool!