Super C research: is Cummins L9 360hp enough?

[Raider89]

We have an interest in getting a Super C coach. My networking and questions among several other coach owners as well as internet research has lead me to Renegade or Newmar. I will be commonly towing a race car hauler <10k or simply towing a Jeep alternatively. My have driven my parents old Monoco 40' motorhome on a few occasions in the CO mountains and definitely noticed it struggling. It appears the Cummins L9 360hp is the engine of choice for most of the single axle size coaches (Renegade Verona, Verona LE and Newmar Super Star). Is this enough engine? Obviously, the dealers say it is and can tow up to 20k trailer. But, it is enough for comfortable easy less stressful driving, especially in big hills and mountains?

I would love to have one of above single axle options for the obvious cost reasons, but feeling compelled to look at Renegade Explorer or large tandem axle models to get to DD 500hp option. I am just trying to get serious personal feedback, as I would hate to second guess my decision or be frustrated with performance after purchase. Given the lack of both new or used inventory across the country, I have not even been able to see or test drive anything of interested yet, wanting to avoid blind purchase decision.

 

[sanda]

We have an interest in getting a Super C coach. My networking and questions among several other coach owners as well as internet research has lead me to Renegade or Newmar. I will be commonly towing a race car hauler <10k or simply towing a Jeep alternatively. My have driven my parents old Monoco 40' motorhome on a few occasions in the CO mountains and definitely noticed it struggling. It appears the Cummins L9 360hp is the engine of choice for most of the single axle size coaches (Renegade Verona, Verona LE and Newmar Super Star). Is this enough engine? Obviously, the dealers say it is and can tow up to 20k trailer. But, it is enough for comfortable easy less stressful driving, especially in big hills and mountains?

I would love to have one of above single axle options for the obvious cost reasons, but feeling compelled to look at Renegade Explorer or large tandem axle models to get to DD 500hp option. I am just trying to get serious personal feedback, as I would hate to second guess my decision or be frustrated with performance after purchase. Given the lack of both new or used inventory across the country, I have not even been able to see or test drive anything of interested yet, wanting to avoid blind purchase decision.

Keep in mind that none of us in the RV world can expect to be able to go up a mountain like we do in our automobiles. With max load/tow weight if you can stay up with loaded semis you are doing well. More important than HP is the torque availability and drive gearing.

 

[Rich W.]

I just looked at the specs for the Super Star and was surprised to see an ISL rated at 360 hp but at least its rated at 1150 torque and it might be worth looking into the cost HP upgrades. Some folks have upgraded the 400hp ISL to 450 and been very happy with it.

The Renegade Velentia though, as of 2021 specs, is powered by an ISB rated at 360/800, so if towing and maintianing speed on a grade is a concern, the Super Star would be the obvious choice. Both being rated at 360hp is a bit misleading. Fuel economy is probably a bit better in the ISB (6.7L) but I would much prefer to have an ISL (8.9L) for the purposes you stated.

My ISB powered Ventana weighs around 30,500 to 31,000 loaded. Its rated at 35000 and 10,000 towing. I dont really notice the difference when towing a jeep, but anything more would bog it down, and I put some effort into planning for grades and shifting manually, and there are more than a few freeway grades that will put me in 3rd despite my efforts. Thats ok with me because Im not in a hurry and Ive gotten used to it and learned to get what it has to offer out of it, but I would much prefer an ISL powered coach.

But because I also want to stay under 35’ and the ISL powered New Aire wasnt offered when I bought my coach, I just have to be satisfied with an ISB. Given the choice on two otherwise similar rigs in price, quality, and other specs, there would be no question about it.

 

[Av8r]

We have a 2021 SuperStar with the L9 engine. Like you, our research ultimately led us to a decision between the Veronas and the Newmar. We tow a Jeep Gladiator pickup, and, until you get into the range of 6 – 7% of grade, it does just fine.

On that kind of hill, though, I regularly see 40mph, and quite often am slowed to 35. I don’t remember having been slowed below that. If you drive that sort of slope regularly, that’s what you’ll be facing. Only you can decide whether this constitutes “enough” engine.

It’s true that the hitch rating on the rig is 20k, but I can’t imagine trying to climb hills with anywhere near that much actual weight behind.

The SuperStar is significantly heavier than the Verona models. As I remember, the difference in HP-to-weight ratio was on the order of 10-12%, favoring the Renegades. I have to think this is a noticeable difference in performance.

This is the biggest drawback to the M2 based coaches, in my opinion. Overall, we’ve been very happy with the SuperStar, but if money were not a limiting factor, I’d look at something with more hp/torque. This would also get you into a Cascadia or similar cab, which is a significant upgrade from the M2.

Feel free to message me if I can be of any help with your decision process!

 

[Raider89]

I fully understand the relationship of HP and Torque, while also understanding one does not drive this type of large heavy coach "like a car". It is absurd how many folks try too. With all due respect and sincerity, I am just trying to get feedback opinions on suitability of 360hp, 1150tq Cummins for these size of coaches and owner satisfaction versus large Detroit Diesel.

 

[Raider89]

Thanks for all feedback above, super helpful.

 

[EasyWay]

I fully understand the relationship of HP and Torque, while also understanding one does not drive this type of large heavy coach "like a car". It is absurd how many folks try too. With all due respect and sincerity, I am just trying to get feedback opinions on suitability of 360hp, 1150tq Cummins for these size of coaches and owner satisfaction versus large Detroit Diesel.

Gearing will also play a role. I have the Dodge 5500 Cab Chassis 30' with the Cummins 360/800. Gross chassis is 20K, tow rating is 10K. The similar Super C coach 31' on a Freightliner Chassis has the same power rating 360/800 however it uses more aggressive rear-end gearing. It's gross chassis is 30K and I think it's rated to tow 15K, maybe 20K. Obviously milage will be reduced but the Freightliner carries more fuel.

 

[skijlw]

We have a Tiffin 40' with the L9 360HP. We tow a Wrangler Limited. We run close to 32K in weight and the Jeep is around 4.5K. The coach pulls most grades at 55 mph with the exception of the highest mountain passes where we have slowed to 35 mph. We have 96K on the coach mostly in western states with plenty of mountains and still running strong. Hope this helps.

 

[PRussell23]

I'm reading this 2-½ years later, wondering what you decided. I have a '23 Verona 36' and tow essentially the same vehicle as you. I agree with the comments about not driving like a passenger vehicle, but I'm sometimes conflicted by comments from others about the performance of their rigs which are larger/heavier than ours but with the same engine. I debate the idea of custom tuning or otherwise modifying my stock setup.