Several people have had good luck towing a trailer with previous model Subaru Foresters. I do not know why mine is different. I just bought a 2004 Forester tried to tow with it. Mine is a nightmare. It is unstable above 40mph. It has a lot of side to side sway above 40mph if there is any steering input. It is almost harmonic in nature - it does not dampen out quickly. If feels like you are driving on Jello. It feels like the problem is much more the tires than the suspension. Though that is hard to prove.
Even when parked if you push on the hitch with your foot the Forester will sway side to side [right and left] a lot. You can watch the rim move right and left in and out of the tire. I think the sidewalls are just really weak. The tread is probably relatively soft also.
The Forester's tires are Yokohama Geolander G900 P215/60 R16 94H. Even in normal driving the steering response and cornering are poor. [Other Foresters may be equipped with 15" tires, and other models of Geolander tires - rather than the G900].
My Mazda MX-6 [much lower car] has Pirelli P4000 P205/55 R15 87H - it is stable, and if you push sideways it does not sway side to side anywhere near the degree that the Forester does. Steering response and cornering are good.
The Geolander G900 has a tall soft sidewall, it is 4.500" above the rim rather than 3.625" for the P4000 [24%higher].
My best idea right now is to change to a shorter and stiffer sidewall tire.
I am considering changing from P215/60 R16 94H
- an "H" rate tire with 60% width/height ratio, to Bridgestone Turanza LS-V 225/50R16 92V - this is a V rate tire so the sidewall is stiffer and at a 50 or 55 ratio it is shorter. This is the V rated version of the tire that some other Forester owners have [LS-H]. The tread should also be a harder sports car like compound.
Some of these tires are rated and discussed on
Does anyone else have any Experience changing to a shorter V rated tire for better stability?
My trailer does great and stable to 85+mph behind my Mazda MX-6, so I do not think it is the trailer. The trailer weighs ~1800lbs [816kg]. The tongue weight is 153lbs [69kg]. The Forester's manual says to keep the tongue weight between
8-11% of the trailer. 8%=144lbs [65kg] 11%=198lbs [90kg]. [the max allowed is 200lbs on the tongue] The manual transmission version of the Forester is rated for 2400lbs [1088kg] towing capacity.I have already tried raising the tire pressure on the rear tires to
41psi [2.8bar] as recommended by the manual. The trailer tires are about 40psi.------ Since my original write up I have learned the following: The dealer told me that the 2004 model is the first to be equipped with the Geolander G900 tires, previous years had a different model tire. This is the only change to the suspension that he is aware of between the 2003 and 2004 model.
The Maximum tire pressure on the tires is 44psi, so I upped the rear pressure to 44psi and the fronts to 41. [for towing the manual says
29psi front, 41psi rear]. I also changed the hitch from a straight one to a "drop hitch" it is now 1.5" lower than the straight one. The drop hitch is about 4.0" shorter than the "lift hitch" [bent receiver hitch] that I originally tried. The hitch ball is on a short receiver. A test drive showed that the lower hitch/ball placement and the higher tire pressures are an improvement. However still not acceptable. I think the higher pressure stiffened the tires but not enough and the tread is still too soft.I have heard another Forester owner has had good luck with 75-100lbs of tongue weight. An additional test drive was done after I moved several items out of the front of the trailer to the back of the Forester. This reduced the tongue weight to 118lbs [down 35lbs from
153]. The swaying seemed worse with the lower tongue weight. [This follows the logic I have heard many times].I would like to hear some other ideas, especially to know if others have switched to better performing tires.
Chris