Bob338

I have the trailer tow package on mine. Made the hook-up much easier. Don't recall what changes, if any, were included elsewhere in the car when I ordered, but it wasn't much best I recall. I'm pretty sure there were no cooling enhancements neither for the tranny nor the radiator. Top limit for hauling was 2500#. Class 2? So that requires nothing more. The advantage when I ordered was the fact that the hitch was installed. After market hitches can be a problem, and expensive, to install. The addition upon ordering initially added very little to the sale price, a fraction of what an after market installation would add. I had a fully loaded trailer, and I think it was a 10' one. My fuel mileage wasn't significantly affected, if at all. I typically get in the very high 30's for fuel mileage. Best I recall that mileage was not remarkable. Only difference in driving was trying to stay under our 55 mph limit for trailers, and staying in the right lane, except to pass per our state law. I'm also sure I paid little attention to the speed limit, as I normally don't!!

slmskrs

Are you saying the max you towed was 2,500#? Or they said with the factory hitch you could only tow 2,500#? The car is rated at 3,500#. I suspected there were no enhancements (cooling) with the factory tow package, just the hitch/wiring. Interesting on your mileage. I get high 30s up to 40mpg (if I only go about 70) when not towing. When I tow the boat (3,500#) for the normal 25 mile round trip (2/3 freeway and the rest local with signals), I get around 21mpg at 60mph. I'm in California (55mph speed limit with trailer), and will be towing the 6x12 trailer from So Cal on I5 over the grapevine. In the central valley on I5 (mainly flat), most big rigs go 60 up to 65 while the rest of us go 80+ (speed limit 70, but on I5 central valley, you go with the flow-middle of nowhere). I don't expect great mileage with the UHaul since the boat has a better slip stream but expect to be going about the same speed as the big rigs. I'll be happy if I make the trip (400 miles) on one tank of diesel (normally almost 1/3 left in the tank on this trip). I'm just concerned about going over the grapevine on a hot day with those twin turbos and the tranny. I do have an ODB reader with separate coolant and tranny temps. Normally they are exactly the same number so initially I thought it was just one sensor data being sent out. But I did notice once a couple of degree difference between the two. I was told by an independent MB service guy that our transmission should go into lock up in all gears (seems odd for 1st or 2nd), but he said what will kill the tranny if it doesn't go into lock up because of heat build up. When I pull the boat, I generally keep RPMs between 1600 and 1800 since it is the optimum torque range.

Bob338

There is/was in issue between ratings in US and in Germany. I picked mine up at the factory. I don't recall what the issue is. I believe the car is only rated for Class 2 in Germany therefore production rates it there. When it gets here it's still Class 2 but by US standards it's really our Class 3. Something like that. I don't care as my towing is only occasional. I considered it at the time because I was contemplating a small vacation trailer and I blocked it out of my mind later. I believe it may be covered in the manuals. I have no idea the weight of the trailer I towed. Lots of tools and house goods. But, I'd guess about 3000#. No issues on pulling power or stopping.

On any highway I typically get about 39 mpg where there are not many stops or slow-downs, and once on a returning trip, middle of the night across the lower San Joaquin Valley, then north, I was exceeding well over 100mph. Got 41mpg on that tank. Love the car. I've never had even a minor problem, and never a warranty claim of any type. It's been 100% perfect. I'm in Cali, know the I5 and the Grapevine. If your boat does weigh 3500# I'd be inclined to make a stop at the rest stop half way up the Grapevine to allow cooling, especially in the summer. From the LA side the climb is more gradual and stair-stepped so no problems going north.

slmskrs

This trip will be a one-way Uhaul rental of a 6x12 enclosed trailer from So Cal to the Bay Area, so good point about Grapevine going north being gradual. I'll just have to watch speed on the way down the last 5-6 miles into the central valley.

I do have to admit when we're driving down to So Cal and start up the Grapevine going South, I love how I've got so much torque in that 4-banger diesel that it's chugging along in high gear at 1800-1900 RPM at 70+mph on the steepest part passing cars left and right....