stuttering in 3rd and OD

[SideSwipe]

I did some searching but no homeruns. My truck when shifting into 3rd and into over drive will stutter very bad before actually going into gear. It does it so bad, when people are in the truck with me, they think im pumping the gas pedal.

The tranny was just rebuilt but did the exact same thing before it was rebuilt.
(i really trust the guy that built my tranny, he's going to look at it this week but i figured id post here first)

any ideas what it could be??

Things to know:
Early 99 7.3 f350 4x4 209,000 miles
Tranny rebuilt and mostly upgraded (including tourqe converter)
Tanny shifted the same before the rebuilt ( except it shifts awesome 1st and 2nd now)
I havent had the truck long and it shifted like this pretty much from the first day i got it.

[ipz2222]

That sounds like tcc chatter. What did the trans guy say about it before he built the trans???

[melmount]

that sounds like its happening at the times when the converter is locking. Mine does it around 40mph and at like 1300 rpm. I think mines an injector misfire. At low rpm with a locked converter its like direct drive, nothing gives. No tc slippage compensating for a motor shaking. Just a thought for you. Maybe have the buzz and contribution tests done to verify its not an injector before ripping the trans apart.
It could be converter chatter but also a misfire.

[SideSwipe]

Originally Posted by ipz2222

That sounds like tcc chatter. What did the trans guy say about it before he built the trans???

i didnt tell him cause i didnt know what it was, i just thought the tranny was going up. (which it finally did)

[SideSwipe]

Oh and i thought of a better way to discribe it on here.
shifts like this:
when the tranny gets to its last 2 gears, before it shifts, the rps will flux 200-400rpms up and down a few times before getting in gear.

[SideSwipe]

I took my truck to amcco to pull any possible codes and a test drive.
at first he said he thinks its motor related, not tranny while doing the test drive. The only codes that came up were p1211 and p1249. He said that a ford dealer has to reflash the ecu to fix one of those two codes (cant remember which one)

Then he went through his tsb's for ford and found a common superduty problem: 200-300 rpm rise in 3rd-4th in upshift. which sounds very close to whats happening with mine. The fix, new solenoid body and a tranny reflash.

Does either one of those sound right?
reflashing from only ford to fix p1211 and or p1249?
new solenoid body and tranny reflash to fix possible shifting problem?

[SideSwipe]

ok what i found out is i have shift flare. Im still not sure if i have to replace the solenoid body and reflash the pcm from a XLE4 to a XLE8 or just have it reflashed without getting a new solenoid body. also not sure wheres the best place to reflash the pcm.

im still doinf some research and calling around but if any one can help that would be great.