How to 8HP Swap an E90 + E92 — Bavarian Auto Parts

Chapter 01 · Before You Start

Prerequisites.

◆Tools

ISTA, WinKFP, multimeter, soldering tools, wiring harness supplies, BMW diagnostic software.

◆Skills

Knowledge of BMW electronics, wiring, and coding, ability to read and understand schematics.

◆Parts

8HP gearbox (E84/E89 N20 for RWD, E7* N55 or E84 N20 for xDrive). Mechatronic from all E-gen 8HP gearboxes are interchangeable. It's also possible to buy F-gen 8HP45 and replace the mechatronic.
8HP gearbox connector or complete used harness. I recommend to buy a complete used harness.
8HP or DCT shifter with 8-pin connector and 6x MQS pins (1x 61136954526 and 6x 61136931880 or 6x 61130056962 when you can't crimp MQS)
N55 torque converter or N20 flexplate (these are 100% compatible with N52 and N55).
CAS3 or CAS3+ module (for EWS4 compatibility).
FRM3 MAX Brose (FRM3 is needed for sure, not sure if MAX is needed)
JBE III M (JBE III is needed for sure, not sure if MAX is needed)
ZF Lifeguard 8 transmission fluid or similar
Oil line adapter (canformance for example) or E84 oil lines

Optional parts

Newer ABG/ACSM module (to eliminate the ghost ACSM DTC).
LCI paddle shifters (or resistors for non-LCI paddles).
Secondary CAS3+ (for XHP license on different VIN).
8HP oil pan and filter
New gearbox bolts and other stuff you change when replacing gearbox

Chapter 02 · The Wiring

Gearbox Pin-out.

6HP Connector

16-PIN · OUTGOING

6HP gearbox connector — 16-pin pinout diagram

01EGS_MGA

02PT_CAN_L

03— unused

04EGS_DOWN

05EGS_UP

06PT_CAN_H

07S_LOCK+

08— unused

0915WUP

10P/N

11S_LOCK−

12— unused

13kl.31

14kl.30G

15ILOCK

16kl.31

GM Connector

16-PIN · OUTGOING

GM gearbox connector — 16-pin pinout diagram

01kl.30G

02kl.31

03P/N

04kl.30G

05kl.31

06EGS_UP

07EGS_MGA

08— unused

09EGS_DOWN

10PT_CAN_H

11PT_CAN_L

1215WUP

13ILOCK

14SLOCK+

15— unused

16SLOCK−

8HP Connector

14-PIN · INCOMING

8HP gearbox connector — 14-pin pinout diagram

01P/N

02— unused

03PA_BUS

04M_LIN

05PT_CAN_H

06PT_CAN_L

07— unused

08— unused

0915WUP

10WIPPE+/−

11— unused

12— unused

13kl.30G

14kl.31

Chapter 03 · The Procedure

How-To.

Step01

Prepare the car.

Convert to EWS4 if needed. Install FRM3 and JBE III. Make sure the DME is programmed with an automatic transmission mapping. This is needed so it supports torque interventions. Make sure the car is updated, especially the KOMBI so it can display the 8th gear. Make sure everything works as supposed before starting this project.

Step02

Remove the old gearbox.

Old gearbox removal — Fig. 02 · RemovalFrame 01

Step03

Put them side by side, compare and drill one extra hole in the 8HP and elongate the other.

Side-by-side comparison — Fig. 03 · Side-by-sideFrame 02

Step04

Prepare and install the torque converter.

Either replace the flexplate to the one your 8HP came with or install the 8HP N52/N55 torque converter. In case of N54 with 8 bolt crankshaft, use N55 torque converter with N54 flexplate.

N20 flex plate will fit on (most) N4* and N5* engines. N55 torque converter will fit on all N4* and N5* flexplates. There are a lot of possibilities here.

Torque converter prep — Fig. 04 · Torque converterFrame 04

Step05

Re-pin the 6HP or GM gearbox connector to the 8HP connector under the car.

GM → 8HP

16-pin · → 14-pin · re-pin map

GM pin Source signal → Target signal 8HP pin

07EGS_MGA→M_LIN (re-use)04

06EGS_UP→WIPPE+/−10

10PT_CAN_H→PT_CAN_H05

11PT_CAN_L→PT_CAN_L06

1215WUP→15WUP09

01 + 04kl.30G (joined)→kl.30G13

02 + 05kl.31 (joined)→kl.3114

SignalCANPowerGroundNot used

Note · EGS_MGA wire is pinned into the 8HP M_LIN position. Parking lock SLOCK± / ILOCK handled separately — see Step 11.

6HP → 8HP

16-pin · → 14-pin · re-pin map

6HP pin Source signal → Target signal 8HP pin

01EGS_MGA→M_LIN (re-use)04

05EGS_UP→WIPPE+/−10

06PT_CAN_H→PT_CAN_H05

02PT_CAN_L→PT_CAN_L06

0915WUP→15WUP09

14kl.30G→kl.30G13

13 + 16kl.31 (joined)→kl.3114

SignalCANPowerGroundNot used

Note · EGS_MGA wire is pinned into the 8HP M_LIN position. Parking lock S_LOCK± / ILOCK handled separately — see Step 11.

Step06

Install new gearbox.

I recommend installing a new oil pan with filter while at it. I advice to replace all the bolts, also the torque converter ones.

Step07

Install the 8HP shifter.

Use the part numbers from above.

At shifter pin the EGS_MGA wire in the M_LIN pin on the shifter. Make new wiring harness with KL30, KL31, 15WUP, PT_CAN_H and PT_CAN_L. I pulled them from my JBE and fusebox.

8HP Shifter · Pinout

6-pin connector · wiring map

Shifter pin Signal Source

1KL30G←Fusebox · +12V battery

2M_LIN←Re-pin old EGS_MGA wire

3PT_CAN_L←JBE III · PT-CAN low

4PT_CAN_H←JBE III · PT-CAN high

515WUP←JBE III · Terminal 15 wake-up

6KL31←JBE III · Chassis ground

SignalCANPowerGround

Parts · 1× 61136954526 housing · 6× 61136931880 (or 61130056962) MQS pins. Pin 2 (M_LIN) re-uses the old EGS_MGA wire from the gearbox harness.

Step08

Reset the gearbox ISN so it can be used in the car.

I used this solution myself: bmw-az.info/egs/33-bmw-e70-7…eter-file.html

Step09

Install one of these zbusb files with WinKFP.

These are all the petrol 8HP45 files for the E-generation vehicles, you can experiment with them:

zbusb · WinKFPpetrol 8HP45 / E-gen

E70/E71 N55 8HP45 xDrive
* 8646496
* 8646502
* 8646500
* 8646494
* 8646498
* 8646504
* 8646492
* 8646490

X1 E84 N20 8HP45
* 7642197 (sDrive28i)
* 8626054 (sDrive16i)
* 7642191 (sDrive20i)
* 7642189 (sDrive20i)
* 8626058 (sDrive28i)
* 8626056 (sDrive18i)

X1 E84 N20 8HP45 xDrive
* 8626050 (xDrive28i)
* 7642193 (xDrive28i)
* 8626048 (xDrive20i)
* 7642195 (xDrive28i)
* 7642189 (xDrive20i)
* 8626052 (xDrive28i)

Z4 E89 N20 8HP45
* 8611957 (sDrive28i)
* 8611953 (sDrive18i)
* 8611955 (sDrive28i)

Step10

Code CAS.

It has to be fully coded as an automatic with SA205 in your VO. Also change these parameters by hand:

CAS · manual parametersset by hand

AUSWERTUNG_P_HW         → nicht_aktiv
ABZUGSPERRE_PLOCK_C6    → nicht_aktiv

Step11

Short the parking lock connector.

Short pin 1 to pin 4:

Step12

Replace the oil pan and filter on the 8HP and fill the gearbox following this procedure:

aftermarket.zf.com/app/contr…505690da53.pdf

Chapter 04 · Wrap-Up

Final.

If done correctly, you can start the car now and test all the gears. Make sure oil is filled take it for a spin and fix any issues if there are. Make sure there are no rattles.

Chapter 05 · Steering Column

Paddles.

Paddle wiring for 8HP. Only LCI paddles will work, or pre-LCI paddles with resistors. So pin 22 from JBE connector X14271 goes to the EGS (as standard), pin 38 goes to ground, 31 means ground. Just reuse old 6hp egs wire. If your paddles are not original and not wired the original way, disconnect the EGS_DOWN wire and wire it to ground.

Use this schematic:

Paddle wiring schematic — JBE X14271, EGS, steering column — Paddle wiring · JBE X14271 → EGSSchematic

If paddles don't work after wiring

Try holding either paddle down for 10 seconds, then try again.

Use this guide if you need to solder the resistors: e90post.com/forums/showthread.php?t=872226

8HP Retrofit Discord (wip)

discord.gg/Y86m3qhq5f

— Written by Alex Naoumov
all credit to him

End · Build Guide · BAP-008

Chapter 06 · Software

Tuning.

Recommended tune

22RPD Custom 8HPe Swap Tune

A fully custom TCU tune built around your car — not a one-size-fits-all flash. Pick the behavior you want and we'll tune for it.

Optional Drag Mode with reduced torque intervention and shift pressures
Gear-specific shift behavior refinement
True manual mode
Gear display in D mode where supported
Support for naturally aspirated and forced-induction N52 setups
Support for N54 8HP swap applications (stock and built transmissions)
Support for rear end ratio changes
Optional kickdown activation or deactivation

No secondary CAS or VIN spoof required. Unlike some other tuning options on the market, this tune runs natively on your car — no extra hardware, no VIN gymnastics.

We offer true custom tuning. If you need a feature we don't already support, contact us and we can look into it.

Available at 22RPD View at 22RPD →

How to 8HP Swap
an E90 + E92.

Prerequisites.