3 (E38) engine swaps/conversion's rev limiting at 5,500RPM's

[tunedportcj5]

Hello David,

Are the ECM & TCM tunes from the same vehicle (i.e. matching tunes) ? Is the wiring harness from that vehicle, or a custom harness, and have you confirmed the pinouts / wiring connects to the components / locations that it should ?

If you need schematics to confirm the wiring continuity I can help with that. Also, some ECM & TCM pairings may have odd speedometer parameters to arrive at a proper signal (i.e. tire diameter of 6 inches, etc.). Looking at the stock, never altered tunes should provide some insight.


Regards,
Taz

They are not from the same vehicle. I have no idea what the original source was (I don't have the tune in front of me to verify). The E38 OS thinks I am running a 4l60 which could be an issue? The T42 is definitely a 4l80e OS. Do you have schematics handy that I could use to verify my wiring is correct? The harness was originally built for a 4l80e. I had to swap some pins and add the ISS connector.

I am pretty sure I tried to log VSS while connected to the T42 on the scan tool. I'll try it again.

thanks for the help!

[Taz]

Hello David,

On the road for the day ... checking in remotely. The tunes not being matched could cause an issue. When you get a chance post the ECM & TCM tunes. What year range TB (throttle body) are you using ... "05-'08 (silver blade) or '09+ (brass blade) ... will check and see if I have a set of matched tunes ... don't see too many Gen IV 4L80s ... lots of Gen IIIs though !


Regards,
Taz

[ScarabEpic22]

David, chiming in with what Taz said, if you're running an E38 originally equipped with a 4L60E (ECM says 4L60E as trans type) with a T42 running a 4L80E OS. Mismatch there could be causing issues.

Post your tune, I havent seen any Gen IVs aka E38s running with a 4L80E (doesnt mean they dont exist), so I might go back to running the T42 with a 4L60E OS then swap the few pins needed to control an 80E with a 60E OS.

[joecar]

David, are you physically running a 4L60E or a 4L80E...?

[ScarabEpic22]

David, are you physically running a 4L60E or a 4L80E...?

80E, post #14 and in his sig.

[Taz]

... I havent seen any Gen IVs aka E38s running with a 4L80E ...

The 4L80 was not widely used with the Gen IV engine. Used briefly in 2007 Gen IV HD trucks. Mainly used in 2008 & 2009 Express / Savana (2500 & 3500 series) full size vans.


Regards,
Taz

[tunedportcj5]

Here are my tunes.. ds_e38_t42.zip

[Taz]

The tunes are both 2007 MY. The TCM looks like an authentic 4L80 tune. The ECM uses OS12614088 - I don't believe that OS was ever paired with the 4L80. I think 2007 4L80 trucks used ECM OS12608677. I don't have this ECM tune on file.

You will either need to locate a 2007 MY ECM tune compatible (originally paired) with the 4L80, or move to 2008 MY tunes. If you change to 2008 MY tunes the TCM can be reflashed with the newer OS, the ECM will need to be replaced with a 2008 (service # 12612384).

The 2008 MY is more swap friendly - most platforms used ECM OS12617631 - Corvette / Truck / SUV / VAN.

Once you settle on what tunes you will use, then we can help confirm the wiring harness continuity - it may vary slightly across applications.


Regards,
Taz

[GAMEOVER]

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[GAMEOVER]

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