HELP!!! BLOWN E40D AGAIN!!

[twatsonhd]

Ive got a 1997 F250 CC 4x4 Auto 345,000
Ive blown the transmission the last 3 times Ive towed up any sort of a grade
I never let it shift in and out of overdrive, but when its really loaded in 2nd gear it seems to shift into 1st and with all that weight and power on it, it blows the transmission apart! I am wondering if any tuners keep this from happening or if there is anyway I can lock it in second so it doesnt try and downshift at such high RPM. I have a tuner on it, cant remember which one but it has a safe tow mode, but I always just leave it in stock tune for towing.

Any help would be appreciated, this is getting expensive!!

[Ryan Rønning]

Get a manual. E40D's are boat anchors from the factory. Unless you have several thousand dollars to put in to it.

[twatsonhd]

Yep, I know. But that doesnt help, or answer my question at all.

[BigFuel]

Locking the PRNDL selector into 2(nd) didn't keep it in 2nd? How much are you towing if you have to be in 2nd to go up hill?