Looking at volvo for hauling heavy 5th wheel RV.

you wont need 500hp to pull a 25k 5th wheel. 400 would be more than enough. remember its the tq that does the work not the hp a 400hp semi will have typically between 1350-1550tq where a pickup would have ?500tq. 500-550 would are normaly in the 1850tq range these do well pulling loads over 100k lbs gross way over kill for what your wanting to do. even something down to the 350hp range would probably do well for you.

i would look for a truck with a single drive Axel vrs a tandem. the single will do better with the low amount of weight sitting on the 5th wheel. i would probably look for a truck geared fast 3.36 or numerically lower get the cursing rpm down for fuel millage. remember that your gross will be less than half of what these trucks normally are going down the road.

 

As Ezrider said. Look at getting a single axle. You need to concentrate more weight on the one axle otherwise you will have a pretty uncomfortable ride and poor braking, pretty much like you are bobtailing. 500HP is way more than you need. You could get a smaller displacement engine. 12-13litre will be common in a normal semi but even look down into the 11L engines.

Have you taken a look at the M2 from freightliner. I have seen the odd one around as a dedicated RV puller for people when they are coming up or returning from snowbirding in the winter. They also make one more spec'd for the job as well.

 

You might go to RV forums and see what people are using to pull 5th wheelers that size.

 

Check the Escapees RV forum. There's a whole section for class 7&8 tow vehicles.
also RV.net forum (i think that's correct)
Have fun!
Mary

 

I run a Volvo 780 with D-13 500hp and I-Shift transmission. If you get a tandem axle tractor you could do a drive axle delete. That will cost a bit of money, but you will have the longer frame to get a tilt deck or similar installed to put your four wheeler on there. I love the Volvo and the I-Shift. I would have the dealer re-program the power settings on the truck to match your application. I do have the 3:36 gears in the truck and it pulls great. I think you should be getting close to 10mpg with an axle delete and keeping your foot out of it.

Reliability on the truck. The truck below is a 2013 has a bit over 156,xxxmls on it. We had the radiator, starter, and some sensors replaced under warranty. No issues with the def or dpf sytems at this point. I have never been broken down and found the tank leak on radiator before it became a problem.

Make sure you get a history on the truck, an ECM dump and so on. That will give you an idea how it has been treated in the past.

 

Petes/kenworth Look pretty, a little more then average maintenance cost, insides not well laid out, poor handling, poor ride, poor control layout

Freightlinerer Look horrible, handle decent, best fuel economy, ride decent, decent inside, cheapest to maintain

Volvo Catalac of trucks, Nice ride, perfect handling, nice inside, easiest to drive, most driver aids, most expensive to maintain,

 

o yea, you only need like 300 hoursies, 500 is way over kill. Ideally you'd get single axle drive with a 2.64 ratio.

 

For what it is worth, back around 2002 or so, I had a friend that bought an old Pete to pull his fifth wheel RV. He had no idea what he was doing, and bought a day cab with a spring suspension. He just beat the hell out a beautiful RV by pulling it with that rough ridding thing.
Salesmen will tell you anything to make a sale. You need to know what you are doing before investing in a truck like this. It would appear that you are headed in the right direction, just by the fact that you are here asking questions!