So I got back to Vancouver a few hours ago, after towing my friends 5000 lb (with trailer) boat down from the Shuswap, and I figured I would do a bit of a write up of my experience. Before anyone asks, no, I didn't take any pictures, because in my hurry to leave last night, I forgot my camera but I wouldn't have taken many pictures anyways, because it was a bit of a rushed trip.

Part 1, Salmon Arm to Kamloops: Right from the get-go, after getting the boat on the trailer at the launch, there were a few problems. The ramp was wet and slippery, and although I have read that it is bad for the drivetrain, I had to put it in 4 hi, if we were going to get anywhere. That minor setback aside, the Durango handled well. Of course it took some time to get up to highway speed, but once I got up to 70 km/h or so (that was how fast the traffic was moving), it was great. It stayed in 3rd and 4th, and cruised very easily, only having some trouble when the traffic became stop and go for about 20 mins (the coolant temp slowly rose to almost red, but still in the safe zone). On this stretch I probably averaged about 12 mpg.

Part 2, Kamloops to Merritt: In Kamloops, I got on the Coke, where I could see how well this thing dealt with freeway speeds. Once moving, it would cruise very nicely at 120 km/h, except for a few steep hills, where it would drop to about 110. On a very slight uphill straight stretch, I got it up to 140 km/h, although it required 4500 rpms (if I remember correctly, or if not, it was enough to have the noise intrude into the inside of the truck) or so in 3rd. I didn't really mind, because the V8 rumble that you only get for a little bit while normally accelerating kept going on and on. It made me feel quite powerful, but when the fuel gauge started almost visibly dropping, I knew I couldn't keep driving like this. My friend was quite impressed with the sound, even though the engine was not as powerful as his [crippled] rig.

Part 3, Merritt to Hope: This is when the slightly underpowered 4.7 began to show that it was overwhelmed. When it came time to conquer the main summit, I could keep up with traffic, but I was in 2nd, and it felt like it could shift into 3rd, and it did, but it couldn't stay in it, so I eventually just locked it into 2nd. Over this 20 km stretch, the DTE dropped by 140 km. As we kept climbing, I noticed the engine losing some power, but it was only right at the top that it affected our speed. If I was going to tow this kind of load frequently on anything but flat ground, I would get the 5.9. Going downhill was uneventful, and engine breaking worked perfectly. I saw another Durango going up to the summit, and he was going along like a raped ape (I know that has been done to death, but I still find it funny). I didn't catch which engine (not that you normally can by looking at it) was in it, but he was going FAST.

Part 4, Hope to Vancouver: This part was the most boring, as it was flat, and the traffic was light until we got into the city. I just stayed at 120, and the engine was lumbering along. I must have gotten the best fuel economy on this portion of the trek.

In conclusion: the 4.7 stepped up to the plate admirably, and was very comfortable for the whole 5 hours. Fuel economy however, was a hernia inducing 7.1 mpg. For my needs, the 4.7 is fine, but as I said, if I was going to do this kind of thing all the time, a 5.9 would be my choice, or maybe a bigger truck. But for all intensive purposes I am satisfied with my purchase.

 

I forgot to say that my friend has taken to calling my Durango "Rambo"

 

update: it seems that I have mucked up my Durango... When I started it up to go get dinner, it started ok, but it was really coarse, and jittery (unbalanced? which makes me think that a few of the cylinders aren't firing). I suspect that it is unrelated to towing (maybe dirty gas clogging the injectors?). I did drive it around town, and it seemed to get a bit better, but the whole vehicle still jerks side to side as the engine is idling. Any ideas? What should I do?

 

You might have gottin it hot and collapsed the head gasket or simply a over worked lifter. Personally, I would give it an oil change with Fully Synthetic (for the detergents) and give her a good drink of some 91 octane.

When you tow up a big hill you want to find a gear (what ever it may be) that the motor likes to stay in comfortable and drop the RPM's to about 3000 so it just hums. If you push a motor you are going to break it. You can't pull the hill like a freakin diesel or V10 so don't try and push the motor to look cool to your friends. Just take it slow and don't break it!


I hope you didn't mess it up but I would change out the spark plugs and oil/fuel.

 

I know... I probably should have taken it a bit easier... but it seems to be a tad better yet, and I will try an oil change and higher octane gas, and see how it does. I may have exaggerated the driving a bit as well though... I probably spent like 40 seconds at 4000 plus, and most of the time it was between 2000 and 3200 rpms. Also, I got an awesome deal on it, and I would have been surprised if something didn't need replacing (even if I may have done the damage). New spark plugs have been on order since yesterday (Champions if I remember correctly).

 

I had my best friend, who is a mechanic, look at it, and it turns out one of the pistons (cylinder 3) had actually broken apart. He figured that it probably had some sort of fracture/crack in it before, and the towing exaggerated it until it broke. Fortunately this didn't do any damage to the engine block. He also checked the other pistons, and they are fine. We went to a salvage yard, and found one in a Durango that had been totalled (rear ended by a semi), and took the piston from it. He is now swapping out the busted piston for the new one (for free ). So all should be fine.

 

glad you found the problem quickly and a mechanic that seems to be a good guy

 

TC, I occasionally tow my 6200 lb ford on a 1500 car trailer without any problems. It's a bit sluggish going uphill, but other than that it pulls excellent. Check out my signature for details.

 

Your Durango seems to sag a lot... doesn't it do damage or something if you tow above the rated capacity? I have to say that based on my towing experience, I could definitely see the engine being capable of towing more.

 

And there it is.