We made the same trip out to Cypress Hills this past week, and without incident. I have learned a lot about towing, and have adjusted my expectations for the R51. I will try to share my experience in as few words as possible
I installed a Bully Dog GT in order to monitor the trans temp (my $400 thermometer). I used the Premium gas program (the only options are Regular or Premium…? I thought there would be a towing program?) The trans temperature stayed around 145°F on the highway with the trailer, and only increased when we stopped for gas, but would drop again after a few minutes of driving. The engine coolant temp stayed around 195°F.
I took Blink32 ‘s advice and kept the shifter in M4 while on the highway, and would shift down to 3rd for some of the inclines. I should have mentioned that this trip has a few hills, we gain about 2,264’ of altitude, starting at 1,876’ and arriving at 4,140’. In 4th gear we were able to cruise along at 90km/h (55mph) comfortably, and would sometimes creep up to 100-105km/h in a slipstream. During the last 50km, around the time that my ears popped, we had to slow to about 70-80km/h (44-50mph) – I attribute this to the altitude, inclines and the wind. When we turned south we had a side wind coming from the east, and it made a big difference to performance. The trans temp went up to 195° as I had to drop down to 2nd and 3rd gear on the last couple of hills, but the temp dropped again when we levelled out. The wind was behind us for the first 350km.
According to the Pathy we averaged 22.1 L/100km (10.64mpg) on the way there, and 20.7 L/100km (11.36mpg) on the way back. I reset the Bully Dog at the campsite, and it calculated our mileage as 14mpg on the way back. The return trip is always a little easier with less weight (no food) and more downhill than up.
PAYLOAD! I did not know about this until recently, but the weight of your trailer is only one factor in towing performance. The R51 has a relatively low payload limit. This is the amount of weight that can be loaded on the vehicle, including people, cargo, hitch weight, etc. The GVWR is 6,113, and the listed curb weight is 4,795, which would allow for 1,318lbs payload. I weighed my Pathy empty, and it was 4,982 with a full tank of gas, leaving 1,131lbs for payload. With 2 adults, 2 teenagers, 2 bikes on the roof, one boston terrier, snacks, pillows, solar panel and my emergency tools, I thought we would be under. We stopped at the scale and came in at 6,151lbs… I had not accounted for the WD hitch and bars which probably add 100lbs! Even at this weight we ran a lot better than previous trips, which included full coolers and a Weber Q in the trunk – probably closer to 1,500lbs.
Tires: I don’t know wtf is up with my TPMS; I set the cold PSI to 35 and largely ignored the TPMS light when it came on. The readings were at ***, 38, 40, 40. The General Grabbers can handle 65psi max, so I wasn’t worried. These tires are ten years old; I'll be replacing them with 285/75/R16 Duratracs in the spring so we'll see if the TPMS still acts up then.
I also kept the R51 in 2WD while towing this time; it was in Auto mode last time. I don’t know if that makes any difference.
In short, my towing issues were more about my own ignorance than the R51. I had been trying to drive too fast with too much payload. She performed as expected, considering the load she was under. My advice to anyone looking to tow with their Pathy?
1. PAYLOAD, PAYLOAD, PAYLOAD!
2. Turn off Overdrive or shift into M4
3. Don’t rush, the Pathy’s a comfortable ride, bring some coffee and enjoy the journey