LB7 transmission failsafe after a tune

[Tapi]

I do not have much experience tuning GM diesels and I did my tune by comparing some in the repository and read some forum posts about this. I did my "99 hp" tune to a '02 Silverado LB7 and it did pick up some grunt. In fact so much that the transmission didn't like the tune.

P0700
P0735
P0746
P0840

These were the codes I read with the scanner. After reflash to stock the transmission works without failures again.

Is the tranny too weak for the tune, is it aging or is there something I should have done in the tune in transmission area?

[staytuned]

Both

[Tapi]

Thanks. You are very helpful!

[Vlad0380]

Assuming that truck's fairly light (2500) and has stockish wheels 80 rwhp or so tune feels a safe bet imho. Heavier, higher mileage and / or multiple limp mode history trucks need milder tunes to be safe. Pyro's a good idea, seen tunes with uncomfortable EGTs, especially with fairly heavy trailers and in higher gears.

Healthy LB7s and Dmaxes in general are pretty peppy even with smaller tunes, see no reason to go into questionable areas with stock tranny.
It limps easier and easier every time and building it is outside the budget of vast majority of Dmax owners this side of the pond.