If it's a vibration which feels like the power unit is shaking on pulling away, up to about 40Mph, then it's normally the front drive shafts. As the inboard joints wear, they begin to stiffen as torque is applied under acceleration. The normal fix is to replace the front drive shafts, however there is a catch. The Freelander is hyper fussy on the actual replacement shafts that are fitted, meaning only genuine GKN shafts are free of vibration. Unfortunately all the aftermarket shafts I've tried, along with many members on here have had vibration issues after non-OE shafts have been fitted. However on fitting genuine GKN shafts (they have unique scalloped inboard joints), the vibration is cured.