The tongue weight are not changed from a 150 to a 115. The four inch frame does considerably help with most 150 rigs getting those frames. The best way is to weight the frame if your seeing too much swing now. The road swing is usually more related to a short wheel base vehicle than weight in many cases. It require u to sit on top of the steering wheel to control things. No doubt more tongue weight does make handling easier, even excess weights are easier yet. To add weight you can bolt weight to the frame if you prefer. If this is not suitable and you require more help let us know.
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