johnydep

I need some info about a trans problem, there is a bit of a story about this one so I'll fill you in first.

About nine months ago my best mates brother in-law rocks up from Queensland driving a brand new 4WD F250 turbo diesel automatic dual cab, he's got a huge caravan on the back capable of going of road and him, the wife & kid are going around Australia.
This guys got a brain like a sponge and he has heard that the transmissions in these things are a severe week link, so he decides to do something about it.
What he does is install a;
SK-4R100-HD2 * * * * Reprogramming kit.
Doubles Low & Reverse Clutch Pressure in Manual Low for
Downhill Hauling, Hi-Speed Pull in to Manual 1, Adjustable ShiftFirmness, Increased Cooling/Lubrication, Improved Converter Feed/TCC Holding

The kit comes with three sections; valve body re-program, pump modification, clutch pack modification.
We only install the valve body side, as recommended by the kit unless overhauling the trans.
After it is all done there is a shudder in reverse under load, after interrogating him he mentions that it was there before but has no become worse.
We contact the local supplier who passes us onto a guy in WA that is supposed to be a god to F series trucks. He tells us that the trans is a poor design & the kits only work with the installation of all the parts.
There is no way I am going to help pull out that chunk of iron, so we pull out the valve body & check everything. Finally we find that the valve body is warped, causing pressure to leak (bloody thing is still new, 15,000km on the clock), so reface & re-install it & re-fill it with full synthetic trans oil again & road test.
It is perfect, the shifts are firm & positive, perfect shift pattern & down shifts with solid feel, an A1 job.
A month later he leaves to travel the rest of Australia.

Tonight I get a call from him with troubles.
He is in Perth & he decided to have the rest of the shift kit installed, they also talked him into a trans cooler (it has a decent factory unit) and a different brand of synthetic trans oil, Penrite (Penrite is not a full syn, it is a Group III).
Anyway, his problems;
On the first hard shift the trans skipped second gear, so it was a 1 - 3 shift. after that the changes were normal, but very soft.
When slowing down and selecting second gear the trans will not go into second unless he blips the throttle lightly.
The trans guy reckons this is normal after having the pump modified with the supplied shift kit parts.
Another trans guy reckons one of the sprags has spun (which he reckons is normal).

He is going to give me a call tomorrow, I told him I would try & get some info for him.

Can anyone shine some light on this?