BMW Gear Ratios

Differential Photos


Top of casing usually has
a tag with the Ratio.


My 3.46 differential from an
automatic 2002 325i

BMW E46 Gear Ratios

The Chart below shows manual transmission gear ratios and Final Drive Ratios for US cars. The chart shows which differentials are interchangeable. NOTE: Additional Modification may be needed to swap differentials. See notes below

Model
1
2
3
4
5
6
reverse
Final Drive
Final drive from Automatic Equivalent
E46                  
323i / ci 4.23 2.52 1.66 1.22 1
-
4.04 3.07 3.46
325i / ci 4.23 2.52 1.66 1.22 1
-
4.04 3.15 3.46
328i / ci 4.21 2.49 1.66 1.24 1
-
3.85 2.93 3.46
330i / ci 4.21 2.49 1.66 1.24 1
-
3.85 2.93 3.38
330i 6sp 4.35 2.5 1.66 1.23 1 0.85 3.93 2.93 3.38
330i zhp 4.35 2.5 1.66 1.23 1 0.85 3.93 3.07
3.64
323cic 4.23 2.52 1.66 1.22 1
-
4.04 3.46 3.46
325cic 4.23 2.52 1.66 1.22 1
-
4.04 3.46 3.46
330cic 4.21 2.49 1.66 1.24 1
-
3.85 3.07 3.38
330cic 6sp 4.35 2.5 1.66 1.23 1 0.85 3.93 3.07 3.38
323i touring 4.23 2.52 1.66 1.22 1
-
4.04 3.46 3.46
325i touring 4.23 2.52 1.66 1.22 1
-
4.04 3.46 3.46
325xi /touring 4.21 2.49 1.66 1.24 1
-
3.85 3.23 3.46
330xi 4.21 2.49 1.66 1.24 1
-
3.85 3.07 3.46
330xi 6sp 4.35 2.5 1.66 1.23 1 0.85 3.93 3.07 3.46
*M3 / conv 4.23 2.53 1.67 1.23 1 0.83 3.75 3.62
-
                 
E85 / E86                
Z4 2.5 (E85) 4.23 2.52 1.66 1.22 1
-
4.04 3.46 3.64
Z4 3.0 (E85) 4.35 2.5 1.66 1.23 1 0.85 3.93 3.07 3.46
Z4 3.0si (E85) 4.35 2.5 1.66 1.23 1 0.85 3.93 3.23 3.64
*Z4 M3.2 (E85) 4.23 2.53 1.67 1.23 1 0.88 3.75 3.62
-
Z4 3.0si (E86) 4.35 2.5 1.66 1.23 1 0.85 3.93 3.46 3.64
*Z4 M3.2 (E86) 4.23 2.53 1.67 1.23 1 0.88 3.75 3.62
-
                 
E83                
**X3 2.5i 4.35 2.5 1.66 1.23 1 0.85 3.93 3.91 3.91
**X3 3.0i 4.35 2.5 1.66 1.23 1 0.85 3.93 3.64 3.64
**X3 3.0si 4.35 2.5 1.66 1.23 1 0.85 3.93 3.73 4.44

A couple of things to notice from transmission gear Ratios
1. Ratios between 5sp and 6sp ratios are essentially the SAME! The 6sp only gives you an extra overdrive gear.
2. BMW uses 2 different 5sp transmission for e46s depending if you have a 328/330 or a 323/325. 328/330 use a ZF transmission and the 323/325 use a Getrag transmission. The gearing ratios between these two transmission are essentially the SAME! What does this mean for you? Gearing for ALL E46s are the same. The only REAL difference is the final drive ratio that BMW chose to put in each car.
3. Some manual transmission cars already come with a 3.46 final drive ratio in stock form. 323/325 convertible and 323/325 Touring
4. E46 M3s use a 3.62 final drive ratio. They're able to get away with using such a high ratio since they have an 8000 RPM rev limit. (vs 6500-7000 rpms for 323/325/328/330s)

* LSDs from M3 / Z4 M3.2 need additional modifications to fit since the differential is larger.
** X3 Differentials have been reported to work on the E46. Additional modifications maybe necessary.

 

©2005 sycE46