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?

[minytrker]

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?

I dont mess with hand helds very much but I have seen them end up being worthless after I have tuned something and the owner forgot to flash it back to stock first.

[skneeland]

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?

I havent tried it, but assuming most tuners are locked to the ecm until you go through the "return to stock" motions. Im guessing that once you flash over the box tune with EFI live (or another box tuner perhaps) that the original box tuner wont recognize the software/ecm anymore and remain in limbo.
As i stated, i havent tried this and am only making an educated guess, but why would anyone risk it for a test? short of maybe losing your tuner module & needing to reflash anyway.

[Straight 6]

I did this with a super chip and a smarty once... i had the superchip tune on there and tuned it again with my smarty... the smarty just overrided the superchips and tuned it like it was never there... i couldnt remove the superchips until i set the smarty back to stock and then i could remove the superchips and eventhough my truck was stock the superchip pulled the tune off and was fine i used it on my truck again and a buddies truck with no issuse... maybe i just got lucky or maybe it was just because it was a superchip but if it helps anyone there ya go lol

i can also say that i tuned my truck with my smarty and pulled the smarty tune off with efilive and havent had a issues yet... although u will turn the truck back to stock with the smarty before retuning with efilive