Tranny jerk!

:confused: I just bought a 98 ram 1500 4x4 with a 360 mag. in it the truck is strong,but my problem is when it goes in 3rd or 4th the if you give more gas like on a hill or it starts pulling harder it starts to shudder,shake like one of the clutch paks or the converter is slipping i changed the oil an filter an adjusted the bands but that didnt help,,,whats your thought on it! p.s.
can i use a 5.1 kickdown lever on this tranny?
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Author: ChargerMan