If it's a later model tranny, they just do that.
It happens at light throttle.
There's a value file in my tuning software that fixes it, but the actual cause, I'm not sure about.
If it just suddenly started doing this, I'd start saving for new seals.
Putting continuous teflon seals in the direct shaft and the input shaft fixes a lot of issues; the ones at the direct clutch shaft can cause low pressure in 3rd and 4th.
If it's the newer tranny, be careful; it really does hit neutral for a sec, and will do a neutral drop if you nail it.
Staying on the throttle while it shifts will prevent it; it's light throttle shifts that cause it.
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
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