Flashing "over" another tune

[MQ105]

Can an EFI tune be flashed to the ECU "over" a box tune, or does the truck need to be returned to stock first?
Conversely, can a box tune be flashed over an EFI tune?

[minytrker]

It depends what box tuned it, some lock the ecu and others dont.

[MQ105]

Can any damage be done by trying? Will it simply either work or not?

What about a box tune over an EFI tune?

[GMPX]

On the Cummins ECM 'everything' is written to the ECM, if you grab a tune from another truck and flash it over the top of what you currently have, your original tune is totally wiped out. To flash a Cummins it's almost at the point of it gets cloned from the file each time you flash.

Cheers,
Ross

[MQ105]

I understand from that explanation that no harm will result from flashing a box tune over an EFI tune, or vice versa...

Is this an accurate statement?

[2007 5.9]

I have flashed over a box tune several times...it's just erases the box tune and writes tfe efi tune over it.

You should pull the box tune first and verify in V7.5 that you have a "ok to flash" message, before you attempt a flash with efi.

~Les

[MQ105]

What do you mean, "pull the box tune first?" Read it with EFI?

[skneeland]

Can an EFI tune be flashed to the ECU "over" a box tune, or does the truck need to be returned to stock first?
Conversely, can a box tune be flashed over an EFI tune?

keep in mind that quite likely your box tuner will be rendered useless after you flash over that tune, prohibiting you from "returning to stock" and/or using it on another vehicle.

[2007 5.9]

What do you mean, "pull the box tune first?" Read it with EFI?

Read the box tune with V8, open it in V7.5, go to calibrations page. On bottom of page it will either say "ok to flash" or "do not flash.

~Les

[CIDRAUGHN]

keep in mind that quite likely your box tuner will be rendered useless after you flash over that tune, prohibiting you from "returning to stock" and/or using it on another vehicle.

Im pretty sure that most tuners will still flash even if they have been flashed over. They are still locked to the ecm, and they should just flash over the efi live tune... someone correct me if I am wrong?