CAT 300 HP vs Cummins

[Evugrandtour]

Hi everyone. I recently test drove a 2000 national tradewinds cat 300 turbo diesel (30k miles) and a 2002 Monaco Knight (60k miles). The tradewinds National feels super strong like a wild horse. I have to step on the brake hard or else the coach will move like the rig got tapped from behind (like when someone rear end you) But before it shifts to second gear, it will refuse to move faster, and then after 2nd gear, it shifts very quickly up to 6 gear. This was my first diesel experience. On a gas I feel like the gear will reach a certain rpm before it shifts gear. So I don’t know if that’s normal for diesel?

Then on the Monaco knight with Cummins 350hp it was very very weak, like there is no push at all and I really thought that it drove worse than a gas. The dealer says because it’s a 40ft heavy coach. He said I’d have to take it slower than most.

I’m trying to understand the engine so I can choose a diesel rig that’s right for me.

I appreciate any input.

[vito.a]

Ask what the engine torque ratings are. Much better way to compare.
Cummins has a 5.9L 350hp engine with 650 ft lbs or an 8.3L 350hp with 1050 ft lbs.

[Mr_D]

In that time period the CAT was 300 hp and 860 ft lbs. The Cummins would probably be 325 hp and 950 ft lbs.
However, there were 330 hp 860ft lbs Cats and 300 hp, 850 ft lbs Cummins on that same period.
We had a 2000 Dutch Star with the 300 Cat and one of my major reasons for going to a 2002 Dutch Star was the Cummins ISC 350 hp w 1050 ft lbs.

[Mile Marker 42]

Originally Posted by Evugrandtour

Hi everyone. I recently test drove a 2000 national tradewinds cat 300 turbo diesel (30k miles) and a 2002 Monaco Knight (60k miles). The tradewinds National feels super strong like a wild horse. I have to step on the brake hard or else the coach will move like the rig got tapped from behind (like when someone rear end you) But before it shifts to second gear, it will refuse to move faster, and then after 2nd gear, it shifts very quickly up to 6 gear. This was my first diesel experience. On a gas I feel like the gear will reach a certain rpm before it shifts gear. So I don’t know if that’s normal for diesel?

Then on the Monaco knight with Cummins 350hp it was very very weak, like there is no push at all and I really thought that it drove worse than a gas. The dealer says because it’s a 40ft heavy coach. He said I’d have to take it slower than most.

I’m trying to understand the engine so I can choose a diesel rig that’s right for me.

I appreciate any input.

That Cummins 350 may be a candidate to have the engine "programed" for better performance. You can check with Cummins by the engine serial number. BTW, Source Engineering sells a new fan blade that actually gives you back horsepower. I know this because I bought one 3 years ago and put it on my 2003 Monaco Knight with the 315. Noticeable difference for sure. Changing the muffler to the Aero Turbine helps too. Here is a link to the fans: Source Engineering Inc | Custom RV Chassis | Eugene, OR and here is a link to the muffler: https://www.amazon.com/Aero-Exhaust-.../dp/B002TRNNA6. Some of the older fuddy duddies on here will chime in saying the muffler is too loud. LOL.

[Skip426]

Power to weight ratio. That's the way to compare apples to apples .

If the 350 hp coach weighs over 5000 pounds more that the 300 hp coach you can expect the performance to be less , Not saying it won't get you everywhere you want to go , just not the same off the line and uphill performance.

As others have mentioned there could be a large difference in the amount of torque the engine produces too . So besides looking at the HP # , you need to know everything about the engine ,

Unless you select the transmission economy mode the 3000 series Allison will hold first gear for a while.

[Rkesselus]

Our 2000 Tiffin Allegro Bus 3126 Cat 300 hp is great like you said it is hell out of the hole which I like. The first shift is hard which I also like. The cat has the power and the Allison 3060 knows when to shift.

[BOOZE TRAVEL]

We have a 02 Tradewinds with the Cat 330. Leaving a light it will be building up turbo pressure in 1st gear and when it hits second gear in about 8', you are gone!
I bought it in 2017 with 70k miles and it was a well maintained 1 owner coach. We now have around 93 with no problems. I do PMs In the fall and head west around New Years for a few months. We get 8-9.5 mpg and run around 70mph most of the time out west. I keep the rpms above 1600 on the hills and usually have to slow down for others that can't keep their speed up.
We weigh around 32k with the jeep attached.
Be sure to keep the water pump bearing greased and the regular maintenance up and enjoy the ride!

[wolfe10]

Originally Posted by BOOZE TRAVEL

Be sure to keep the water pump bearing greased and the regular maintenance up and enjoy the ride!

Actually, it is the FAN HUB bearing that has a grease zirk.


Also with that engine, you have a separate V belt that drives only the water pump. It is NOT on an automatic tensioner like the serpentine belt. Easy to check its tension from below/the ground looking up just to the driver's side front of the engine (back of coach).

[BOOZE TRAVEL]

I will also add that our Tradewinds is well built. No rattling, does well in wind and traffic, it is a solid coach that is a pleasure to use.
It has a Spartan chassis which probably helps.