I just got my 2003 6.0 F-250 back from the dealer. My main complaint was lack of power, along with the rest of the normal stuff. The Service Writer said I had the latest program (30.11) and that nothing was wrong. When I drove it home I got on it a couple of times to see if they had done anything. It hadn’t got any power back, but I did notice it short shifts. When I first got it the full throttle shift point was 4000rpm now it shifts at 3500rpm. This certainly would account for the loss of power. Has anyone seen this or know what is going on?

 

I have had them have the battery disconnected which wipes out the TCM memory and it has to "learn" to shift all over again.

 

I told the Service writer "I might disconect the Batt. every night" and you would have thought I had just turned green from the way he looked at me.

 

Yeah, I experienced the same thing when I took mine in for a totally unrelated problem to the engine. They reflashed it and the first thing I noticed was the short shifting and the obvious loss of power plus the noisy idle ( they disabled the pilot injection) I took a real "performer" of a truck into the dealer and they sent me out with a slug. I called them back to have it changed back. They basically said "Good luck Charlie, it will never happen")- - - Get a Preditor and you won't even want to get back what Ford took away from you . Do it!

 

I talked the Customer Service Rep. and she all but told me to take it to arbitration. They are buying back trucks with the problems mine has. I just might try it.

 

I wouldn't think the short shifting is the reason for the lost power, or the reason why it feels like it lost power. 4000 rpm is way past the power band for these engines (I think red line is 4200). Going much past where your power is isn't doing much.

 

Full throttle shifting at 4k is what you want??? It seems to me and the dyno charts will attest that power drops off at 3500 so why push to 4? In manual F550 I shift at 3500 cuz there's nothing after that. And in my F250 auto the tranny shifts at 3500. What's going on guys? The 250 is an 04 the 550 an 03 both with a 6.0. Is there that much difference after the flash. My 250 CC Fx4 Lariat will damn near smoke the tires from a dead stop? Were your trucks laying black before the flash with no power adders??

 

From a friend of mine:
and a friend to all performanc..Vic
There are physically 6 gears.....it is a 6 speed transmission (both literally and at the software level). Gear six is in fact overdrive.

It is marketed as a 5 speed, and they call 5th overdrive at the marketing level.
(While accelerating, the 5th gear you hit IS overdrive, but this doesn't mean that it's "5th gear". 4th is skipped.
There are times that even 2nd is skipped during light acceleration.

I speak on the calibration level, not on the marketing level. I don't care about marketing; I care about what actually is.
Ford simplified by calling it a "5 speed" to "simplify" things (hahhahahah!) because only 5 gears are used during acceleration.

It is a 6 speed tranmission, but it only uses 5 of those gears for upshifting
1,2,3,5,6
6th is in fact overdrive.

I promise you, there are 6 forward gears in the transmission

Good stuff, and just FYI for this thread.

 

I'm not necessarily advocating a 4000 RPM shift point but this seemed like a good time to point out that shift points are also dictated, to a degree, by the RPM drop from the shift. It's not as likely to be critical on a diesel, but I will say that some gassers drop too far below their torque curve if you were to shift at peak torque or horsepower. In some cases you get quicker acceleration if you over rev them a bit to wind up back in the meat of the powerband after the shift.

Regards,

Morris

 

Now what we need is an electronic shift button on the steering wheel like
F-1 cars. Wow!

 

The tranny is govern to shift at 3600 rpms. the only way to redline it is to shift it manually.

 

The problem with redline is the power curve falls off before redline.
However, you are correct….that is the only way.
I have never understood why one would want to.

 

About that whole 6 speed auto tranny. I was under the impression that there are 5 actual gears and that sixth "gear" you feel is torque convertor lockup. Lockup will happen when you get to a steady cruising speed. Try this next time you get rolling from a dead stop. Watch the tach, under half throttle acceleration you should see it climb and drop 4 times then once you have reacher overdrive "or 5th gear" keep an eye on the tach. you'll see it drop about 200 more rpm. That's the torque convertor locking up. I wouldn't say it is impossable to have a 6 speed. But 6 and lockup?!

 

NO....There are physically 6 gears.....it is a 6 speed transmission (both literally and at the software level). Gear six is in fact overdrive.

It is marketed as a 5 speed, and they call 5th overdrive at the marketing level.
(While accelerating, the 5th gear you hit IS overdrive, but this doesn't mean that it's "5th gear". 4th is skipped.
There are times that even 2nd is skipped during light acceleration.

I speak on the calibration level, not on the marketing level. I don't care about marketing; I care about what actually is.
Ford simplified by calling it a "5 speed" to "simplify" things (hahhahahah!) because only 5 gears are used during acceleration.

It is a 6 speed tranmission, but it only uses 5 of those gears for upshifting
1,2,3,5,6.......6th is in fact overdrive. IT REALLY IS A SIX SPEED
I wish it had seven

 

I'm not a Trannyologist so anyone with more indepth info chime in. I think having a 6 speed auto would be killer!