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I have a 2008 Tribeca which is fitted with a Subaru tow bar. It is rated at 2000kg witha TBW of 160kgs. I have been receiving conflicting advice about using a weight distribution hitch on this vehicle. I have contacted Subaru Assistance and was advised that they are not recommended even though the Owners Manual states their use is of assistance in limiting "Snaking". I would like to hear from anyone that has a 2008 Tribeca and has towed with either using them or not using them.

I just found this;

Towing
The Tribeca has a towbar available as an accessory under part # L101SXA100K.
This genuine towbar allows the Tribeca a maximum towing capacity of 2000kgs and a maximum tow ball download mass of 100kgs. L101SXA100K is not suitable for use with a load-levelling hitch.
The Tribeca is factory fitting with an external Automatic Transmission cooler and does note require an additional accessory oil cooler when fitted with a towbar.

Maybe have try TJM/ARB etc...