RV Review: Dynamax DynaQuest XL 3400KD Super C

By Tony Barthel
We used to have a neighbor who would race cars. He loves his Dynamax Super C motorhome because of the incredible towing capacity, which made sense for the enclosed car carrier/garage wherein there would be whatever he was racing at the moment along with enough tools and supplies to fix it when he crashed. 

He crashed a lot. 

But that Dynamax Super C was immaculate every time. I took a look at a 2021 Dynamax DynaQuest XL 3400KD Super C motorhome to see how these have been upgraded since I saw my neighbor’s. 

The first thing I can say is that all the reasons he had his are still valid today. The DynaQuest XL 3400KD is based on a Freightliner chassis and is motivated by a Cummins 8.9L diesel engine good for 450 horsepower and 1250 ft-lbs of torque, which is a truckload by my own description. 

That much power means that you can hustle this beast up and down hills with a decided amount of ease with the 20,000 lbs. it is rated to tow along behind it. I think my neighbor’s trailer was somewhere in the neighborhood of 10,000 lbs., which is more than my full-sized pickup is rated to tow but half what this machine is able to tug along. Now you see one of the primary reasons people buy these. 

It’s a truck. Just a really, really nicely outfitted one. The interior is quite nice indeed, with polished tile floors and beautiful hardwood cabinets. I like the model with the couch that has dual recliners that also feature heat and massage. Oh, sure, you can go out and race your cars or you can sit in here and watch Jimmy Buffett’s concert replays on the big TV while he belts out his songs on a Bose soundbar. 

Let me know how you did out there. 

This coach is all-electric so you’ve got an induction cooktop and a convection microwave. If you haven’t tried induction cooking yet, I love it. The speed at which you can get things done is impressive. 

Another plus of an induction cooktop is that it consumes very little space vertically. That means Dynaquest can put a bunch of drawers below the cooktop where you might otherwise expect to find an oven. 

Making that electric magic happen is a 2800-watt Magna Energy inverter with three 4D AGM Intimidator batteries. That translates to about 600-amp-hours of juice aboard. If you manage to go through that, there is a Cummins-Onan 8000-watt diesel generator to put the buzz back into the batteries. 

By my calculation, that’s 130 lbs. per battery times three. When you have to replace those you’re going to want to call someone on the level of Arnold Schwarzenegger because Dynamax put them in an exterior storage compartment with a lip and I could see lesser weightlifters ending up in the hospital. Someone should show Dynamax the nifty battery drawers in other coaches – for almost $400K list, that would be the least they could do here. 

Since we’re outside looking around, I like that all the storage bays here can be locked and unlocked with the keyless remote for the coach. I was just saying this weekend someone should figure that feature out in a travel trailer. Maybe I was a few hundred grand out of that league. 

As regular readers will know I don’t like the swooshes and swirls of most RVs, but this is a hand-finished paint job that has some real depth to it and I’ll admit I don’t dislike it. But there are no stickers which makes a world of difference. 

Up above are two Girard awnings that don’t have any arms down the side of the coach and cover the entire side of the coach body. These also have wind sensors so you don’t have to explain to your insurance company how it wasn’t your fault. 

One of the benefits of a Super C is the cab-over bunk area. You could use it for storage or even for, gasp, other travelers. That bunk, by the way, is a $1,942 option, so I wouldn’t be surprised if you didn’t check that box. 

Those bunk sleepers have nothing on the people in the king-sized bed in the back who are treated to an InnoMax air mattress that allows each individual on each side to adjust the mattress to their comfort. Essentially this is a Sleep Number-style mattress but from a different brand. 

The closets in the bedroom are cedar-lined. All the cabinet facing is hardwood. The shower is lined with Corian. And there’s a Sony BlueRay player instead of the DVD player found in so many RVs that is a relic from movies past. 

You can also outfit this model with a washer and dryer, which is great for keeping your race uniforms clean. 

I like that the bathroom vanity and sink are outside the toilet/shower room, but I’m sure there are those who don’t. It allows you to brush your teeth while someone else is taking a shower. Or whatever. 

They’ll be loving that the hot water source is an Aqua-Hot 450D water heating system. 

One other thing – there aren’t all that many windows on the camp side which means you can’t keep an eye on your crew except through a smallish kitchen window. 

I would love to drive this with that diesel engine rattling under the hood. It would feel like driving a big truck because, well, it is a big truck. There are even air seats for the driver and passenger and cameras for both side and rear views. 

I don’t see a lot of Super C motorhomes – but for those for whom this makes sense, this would certainly be a nice way to spend the day at the races. Or anywhere else, for that matter.

One more thing. Could Forest River’s website be any worse? This isn’t Dynamax’s fault, but Warren Buffett needs to open the purse strings and realize that someone spending tens of thousands of dollars on an RV might want more information than a floor plan and the basic specs of the unit. Forest River literally has the worst website in the business and, come on, it’s almost 2021. My local coffee shop has a better website.  

These RV reviews are written based on information provided by the manufacturers along with our writer’s own research. We receive no money or other financial benefits from these reviews. They are intended only as a brief overview of the vehicle, not a comprehensive critique, which would require a thorough inspection and/or test drive.