Help!! 08 3010 Trans Diesel Severe Decel / Engine Braking

[OKCMULE]

Newb here, so any help would be greatly appreciated.
We have a 2008 4x4 Trans Diesel that has been great up until now.

While driving, any time you release your foot off of the accelerator pedal it will decel to the point of almost locking the rear wheels up and will basically use the unit as an engine brake. The slower you go the less noticable it is but regardless of your speed it is fairly violent, literally like downshifting a manual transmission car at 50mph and dropping it from 3rd gear to first and dumping the clutch. The Mule will do this in high/low and is something that is new. If anyone has any pointers please throw them my way.

not that it matters but I have a lift kit and SS rims and larger tires on the unit. Only other mods are an amp and speakers.

[KAWMECH]

The problem is going to be inside the drive or driven convertors