Newmar Ventana

[DLane]

Hello,

I am a new member and have some questions about Newmar Ventanas which I am looking at for our first MH.

First, on paper the wheelbase to length ration is around 53% which is a little on the low side which could mean the coach could wander a little and be affected by wind and trucks passing. Add to this the new (non-adjustable) Comfort Drive added in 08 which requires very little presure on the wheel. I was concerned that the combination of the two might result in a sensation that you are not in control of the coach going down the road. All the comments I have been able to solicit indicate that owners are very satisfied with the way their Vantanas handle (pre comfort drive - 07 models and with comfort drive - non adjustable in 07). I am looking for additional comments from anyone who has knowledge of and actual experience with these coaches.

The second issue I am concerned about is engine power. The 07s have a Cummins ISC 330 hp engine with 1000 lb-ft of torque at 1400 rpm. The 08s have a Cummins ISB 350 hp engine with 750 lb-ft of torque at 1800 rpm. As a point of reference the 09s, which I am not shopping, have a Cummins ISC 360 hp with 1050 lb-ft of torque at 1400 rpm. I have driven the ISB 350 and did not find that it had a lot of accelleration, but I have to admit I am not used to driving a DP. My only point of reference is driving a car and an Itasca gas coach we rented a year ago. I am looking for comments/thoughts/experience with these engines. For the 07 and 08s, my sense is that the ISC 330 would have more power for hill climbing than the ISB 350 due to its higher torque even though it has less horse power. Unfortunately, I expect it may not do as well as the smaller ISB on fuel economy.

Thanks for any comments provided.

[DLane]

Hello,

I am a new member and have some questions about Newmar Ventanas which I am looking at for our first MH.

First, on paper the wheelbase to length ration is around 53% which is a little on the low side which could mean the coach could wander a little and be affected by wind and trucks passing. Add to this the new (non-adjustable) Comfort Drive added in 08 which requires very little presure on the wheel. I was concerned that the combination of the two might result in a sensation that you are not in control of the coach going down the road. All the comments I have been able to solicit indicate that owners are very satisfied with the way their Vantanas handle (pre comfort drive - 07 models and with comfort drive - non adjustable in 07). I am looking for additional comments from anyone who has knowledge of and actual experience with these coaches.

The second issue I am concerned about is engine power. The 07s have a Cummins ISC 330 hp engine with 1000 lb-ft of torque at 1400 rpm. The 08s have a Cummins ISB 350 hp engine with 750 lb-ft of torque at 1800 rpm. As a point of reference the 09s, which I am not shopping, have a Cummins ISC 360 hp with 1050 lb-ft of torque at 1400 rpm. I have driven the ISB 350 and did not find that it had a lot of accelleration, but I have to admit I am not used to driving a DP. My only point of reference is driving a car and an Itasca gas coach we rented a year ago. I am looking for comments/thoughts/experience with these engines. For the 07 and 08s, my sense is that the ISC 330 would have more power for hill climbing than the ISB 350 due to its higher torque even though it has less horse power. Unfortunately, I expect it may not do as well as the smaller ISB on fuel economy.

Thanks for any comments provided.

[Spikester]

First, and foremost, welcome.

One thing you did not mention is what the length of coach you are interested in, furnishing this may allow responses from owners of similar length coaches. Hopefully the moderator will link your post over to the Newmar forum where there are several very active 07/08/09 Ventana owners of various lengths with various power plants.

I own a 34 ft 08 Ventana with non-adjustable Comfort Drive, powered by the 350HP ISBXT. I can address your wheelbase to length ratio inquiry as I am on 190" Wheelbase. This ratio was a big concern as the length of Class A Gas powered motorhomes continued to grow with limited chassis availability. The thing one must consider with the wheelbase to length ratio in a DP is that the motorhome is more centered over the wheelbase than gas Class A motorhomes therefore it is much less of a concern. Also large weight items (fuel tanks, water and waste tanks, main storage is all between the wheels, not behind, or towards the rear. Also tail over-hangs are much less, combine all of these factors with larger wheels and tires, heavier, and air suspension then you get better handling and ride.

Comfort Drive takes some getting used to, especially coming from a gas Class A chassis. It does give you a light feeling steering wheel, but at the end of a day, you don't feel as if you have been wrestling a 15 to 20 ton raging bull down the highway. I find my biggest cause of wandering with Comfort Drive is over-steering by me, the driver, my previous 3 motorhomes required driver input/correction at all times, Comfort Drive requires the driver sit back, relax, and enjoy the drive. I do not experience wandering from "normal" side winds, head winds, truck wash when behind trucks, or aero push from passing or when passing trucks. I drove this motorhome between Barstow and Needles CA on I-40 last January during the windstorm that blew down the RV show tents and reeked havoc at Quartzsite. I was affected by the side winds, but the Comfort Drive made the drive way too easy for the conditions. When I got to Needles I found out that I had been driving in sustained side winds of 45MPH with gusts to 70MPH, I was amazed! I felt as if I was in total control of the coach at all times, no inadvertent lane changes or movement into other lanes, just set the wheel and continued on, wandering a bit, but nothing compared to any other motorhome I have driven. This motorhome is effected less my side winds than my Nissan pick-up. Would I do it again, no, but at least now, I know the capabilities of Comfort Drive. I have not driven a coach with adjustable Comfort Drive; the only advantage that would seem to be gained is giving you a heavier feel to the wheel, whether that is good, bad, or otherwise is probably subject to individual opinion. I do know one thing; I would never own another motorhome without Comfort Drive!

As for the performance of my 08 Cummins 350 ISBXT, with the Allison 3000MH 6-speed, in a coach with 38K GCVWR it is over-powered, but it is only 34'. Diesels are not known for the standing start, flat out, acceleration that you get from gasoline engines, if you are looking for that acceleration stick with gas power. Given that, I have yet to find an on-ramp that I couldn't accelerate to highway speed before merging. Driving a diesel takes some getting used to, once that is done you will find them very easy to drive. When I test drove a Ventana I too thought what a slug when it came to acceleration, but now that I am used to driving the diesel it is not an issue. Traveling here in the Northwest, we find confronting 6% grades the norm, rather than the exception. When towing our boat, car, or pick-up we confront these grades with cruise control set at about 61MPH (1750RPM), transmission in the economy mode, we can maintain speed between 57 and 61 MPH. On extremely long grades, we may have to manually limit transmission to 5th gear to prevent hunting between 5th and 6th. If we want to burn more fuel, and stay at 61MPH, the transmission is shifted to normal mode. The best thing about operating this way is my calculated fuel mileage over the last 4000+ miles, we have averaged 12.3 MPG, this is with, and without a tow, but mostly with a tow. Without a tow, I have gotten up to 14MPG on long level stretches. I am extremely happy with the performance of the 350 ISBXT power plant in our configuration.

Spike

[MonacoMama]

Spike...
I actually moved the thread since it is a Newmar specific thread...I sm sure there will be more folkd in thr Know!

[GaryKD]

Hi DLane,
Welcome to iRV2. I can speak only to the Cummins ISC engine. Take a look at my signature. The details of engine and weight are there. I have 43K miles on my coach. Patience is required on long up hill grades (ex. Rocky Mtns). This means I am not in the fast lane, but I am not the slowest "truck" on the road. The coach has enough power to pass slow moving trucks. On long trips (over 3K miles) I will average 7.2 to 7.4 MPG at 60 MPH on the Interstate highways. Overall I am please with the ISC. I would make the purchase again.

[Dav5942]

WOW, what a big difference between 350 ISB 33'(12.3 mpg) and the 330 ISC 39' (7.3 mpg)! Does the weight actually make that big a difference?

[porscheracer]

In all fairness . . . if you're getting an average of 12.3 out of a 350 ISB in a 34,000# coach, you need to take that engine to Cummins to see what they can copy off of it. That is phenomenal.

[MarcW]

I also have the little shorty 34' Ventana. Mine is a '07 so no Confort Drive. I admit that when I first started driving it, I was up on the wheel some to keep it in a straight line. It wasn't real bad but did become tiresome not being able to really relax. After some time, I found that 90% of that was just me over correcting. I have since added a set of Hendersons role control valves and a Steer-Safe setup on the front end and now it goes down the road with finger tip control on the wheel. Very stable and comfortable to drive. Crosswinds and trucks have little effect. At this point this coach will make a good argument against the wheelbase/ratio absolutes that some use for straight line stability.
The ISB engine is very fuel efficient. Mine has the small block 300hp/660tq version. I added a Banks powerpack that brings it up over 400hp/900tq. At a loaded weight of 26,000 (max gross is 28,000) with a 3500 toad, I haven't found a hill it doesn't love.
In my opinion the ISB engine, if paired up with a coach that isn't too heavy for it, will return the best fuel economy in the RV world.
I see a average of 10 mpg in the western half of the country. That's 65 mph on the hwy and alot of 6%+ grades. The computer said it was getting 13 mpg on level I-5 in central Calif. That may or may not be accurite but it did average 10 with alot of hill climbing on that trip.
One thing about the ISB that is most noticable as a first impression is the turbo lag that is responsible for very sluggish acceleration from a stop. Once it spins up (the other 99.9% of the time you're driving) it has good pulling power.

[69RoadRunner]

My 09 Ventana 3942 has adequate accelleration. It can take a little time to recover speed when you're on a hill, but it's ok. Using cruise control seems to make things easier.

When I towed my Road Runner on an aluminum trailer, I noticed no difference in accelleration.

This is my first motorhome, so it's hard for me to compare mine to non-Comfort Drive MHs. I have the adjustment around 2.5, which is supposed to be close to the non-adjustable setting in 08.

[DLane]

Thank you all for responding. Your comments were very helpful. Sounds like Comfort Drive is a good thing and that road stability should not be an issue with a 39' Ventana (I hadn't mentioned lenght as one of you noted). Sounds like at least some people who have the variable Comfort drive set it at about the same level as the non-adjustable units.

With your input so far, I would like further comments on how the Ventana 39 footers with the ISBXT 350 in particular handle road grades with a toad in tow. In particular I am interested in this info for an 08 model. One of the reasons I have thought about this is that the 07s had an ISC 330 with more torque than the ISB used in the 08s and that the 09s have gone back to the larger displacement ISC (360 hp now).

Thanks again for your comments.

Don

[Spikester]

Porscheracer,

I think the main key to my exceptionally good mileage is the climate in which it the coach operates. The temperatures here in the Pacific Northwest are on the cool side most of the year, therefore the radiator cooling fan rarely comes on. I drove the coach to Eugene OR last week, about a 250 mile trip, engine coolant temperature never got above 200 degrees, averaged around 183, so the cooling fan never came on. It was on my trip South last winter before I heard/saw the effects associated with the radiator cooling fan operation, this did not happen until I was pulling the hill out Needles CA, heading South on HWY 95 towards Parker AZ., scared the heck out of me when it kicked in. The radiator fan is a mileage killer, when it comes on it drops the instantaneous mileage reading close to 5 MPG, if I was operating in a milder/warmer climate my fuel mileage would be somewhat lower I'm sure. The only warm weather driving it has been operated in is Tucson & Yuma during February and early March. Weight of coach is only around 25K (28K GVWR), try to keep it lightly loaded, haven't had it long enough to accumulate a lot of stuff, also travel with very little water in tanks. Never in a hurry, spend 95% of the time in cruise control with transmission in economy mode, this keeps RPM right at, or just below, peak torque RPM. Do my best to keep out of situations that will cause me to lose momentum. This coach has exactly the same running gear that the 39ft 38K GVWR models have, so as I said before I am over powered as heck, most of the time the engine is just kind of loping along with a very low turbo boost just waiting to be loaded up.

Spike

[69RoadRunner]

I'm averaging 9 mpg with my 2009. I couldn't tell my Road Runner was back there when I towed it on a trailer.

The car and trailer weigh around 5500 pounds. I didn't go up any mountains, though.

[MarcW]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Spikester:
Porscheracer,
I think the main key to my exceptionally good mileage is the climate in which it the coach operates. The temperatures here in the Pacific Northwest are on the cool side most of the year, therefore the radiator cooling fan rarely comes on. I drove the coach to Eugene OR last week, about a 250 mile trip, engine coolant temperature never got above 200 degrees, averaged around 183, so the cooling fan never came on. It was on my trip South last winter before I heard/saw the effects associated with the radiator cooling fan operation, this did not happen until I was pulling the hill out Needles CA, heading South on HWY 95 towards Parker AZ., scared the heck out of me when it kicked in. The radiator fan is a mileage killer, when it comes on it drops the instantaneous mileage reading close to 5 MPG, if I was operating in a milder/warmer climate my fuel mileage would be somewhat lower I'm sure. The only warm weather driving it has been operated in is Tucson & Yuma during February and early March. Weight of coach is only around 25K (28K GVWR), try to keep it lightly loaded, haven't had it long enough to accumulate a lot of stuff, also travel with very little water in tanks. Never in a hurry, spend 95% of the time in cruise control with transmission in economy mode, this keeps RPM right at, or just below, peak torque RPM. Do my best to keep out of situations that will cause me to lose momentum. This coach has exactly the same running gear that the 39ft 38K GVWR models have, so as I said before I am over powered as heck, most of the time the engine is just kind of loping along with a very low turbo boost just waiting to be loaded up.
Spike </div></BLOCKQUOTE>

Totally off subject but......this is interesting.
My fan cycles off and on continuessly. The temp is either rising to 208 where the fan comes on and then back down to 200 where it shuts off and repeats. I have read where this is common with other Cummins powered coaches and when I asked them about it, the 'tech' said it is what they are sposed to do. I was also told that the 'new' motors are meant to run at higher temps (200+*)and that is one of the reasons they get better fuel econ.
I'm not a diesel engine expert so knowing what is true and what is not is still a question.
I do know that the fan obviously puts a load on the motor. I can feel it and it would be alot nicer if the thing stayed cool without it needing to run except under a heavy load. If that fan wasn't running I could see where this thing might get 12 mpg.
I have a feeling that my rear radiator isn't getting the airflow it needs to stay cool without the fan as it doesn't make any difference on the outside air temp. I'm wondering if the '08s with the 350 ISB have different radiator ducting than the '07s.

[NEILSJEWEL]

My 34 2007 ventana had the same setup.On the flats in fl i hadly made 10 mpg
When the fan shuts off those great big blades and shroud block the air flow!!!!!

Newmar can add a 2 speed fan approx 1500.00

I now average 10.5 thinking I can do better?????

now the temp stay just under 200 degress

neil in naples