48re delayed 3-4 shift

[Lair87]

I've got a 2003 dodge with a 48re transmission. The transmission has a trans go shift kit, billet triple disk converter. Recently I'm having trouble with the 3-4 shift being delayed a lot longer than it used to be. It shifts every time, just not where it usually does. All the other gears are normal and shift fine and where they should. Lock up is firm. I tried adjusting the tv cable and replaced the throttle position sensor and that didn't fix the problem. The scan tool I have will hook to the pickup but not read all the data points, so I'm not exactly sure what it's being told to do. Basically I want to figure out if it's a mechanical problem in the transmission or the computer causing the issue? Has anyone ever had an issue like this? Thanks for any input!

 

[Lair87]

Okay I hooked up a couple pressure gauges to the transmission and watched the line pressure and overdrive pressure. At idle in gear line pressure is about 68psi and the line pressure doesn't change in any gears until it shifts to overdrive. When it shifts to overdrive the line pressure goes to 100psi and the overdrive pressure goes up to 50 then up to 140psi. Is that normal for the line pressure to go up in overdrive? or do I have a leak going on?