10-25 mph roll. Won't Down Shift.

[96FirebirdFormula]

Well i noticed when i turn a corner or followin someone that turns if i punch it down at 10-25mph it won't downshift it hits the redline then shifts. Its like the tires are spinning but there not. think its in 3rd gear. from 35mph+ It downshifts fine. and from a stop it shifts fine.

Tranny Serviced last summer New Filter & Fluid Car has 119k on it now.

[Craig 94 TA GT]

Are you sure it's in 3rd gear? What rear end do you have, 2.73s or 3.23s? If you have 3.23s and hit redline, what MPH is that? If everything is properly working and you hit 2nd gear redline with those gears, you'll be going close to 80. With 2.73s, closer to 95. If you are not anywhere near those speeds, then your tranny is slipping. If it truly is in first, redline is around 45-50 with either gears.