Normal Shifting?

[cruffleluficus]

Hi all. This is my first post here. Still new to the Powerstroke, so trying to read and learn some stuff. The truck in my sig is actually my 3rd SD, had an 04 and an 03 before, but both had the V10. Totaled my last one this winter (gotta love Ohio winters) and I've only had this one a month or so.

My question is, when going through the gears (automatic), it shifts great from first through 3rd, but then lingers a bit and suddenly goes straight to OD. Sometimes it will do right and go 4th then OD, but more often not. When it's still cold and not using OD it will go to 4th just fine. If I'm heavy on the throttle, it's not so bad, but if I'm easy it's worse and sometimes goes to OD somewhere between 35-40MPH. Is this typical and just different because it's a diesel, or maybe something I should look in to. I haven't tried to de-tune it yet, it has an old Superchips 1700 and is set on tow mode. My other SD's didn't go to OD until about 45.

Thanks,
Chris

[ponyponer]

that sounds a little low. mine goes to od at about 40-45 mph. when i keep my foot on the throttle it goes right after 4th. if i don't wind them it goes a little slower into od. is this the 99 f250 with 85000 miles in your signature that you are speaking of?

[Jake]

Try taking your tuner off tow mode first off, that will change your shift strategy. It could also be your PCM trans strategy. BTW, its a 4 speed tranny. It feels like 5 gears, but one of those "gears" is actually your torque converter locking up. You can tell because before it locks, you can put the pedal down and your RPMs will increase alot, and after it locks, when you put your foot down harder it will seem like manual transmission, the engine RPMs will not increase.