Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Discussions => Topic started by: folivier on March 07, 2018, 09:26:15 am

Title: Towing performance?
Post by: folivier on March 07, 2018, 09:26:15 am
We've decided that a 36' is what we are looking for.  Haven't decided on whether we want a slide in front or not.  We've had both in our Newells so understand the differences and issues.  Won't be full timing but will take trips of a couple months or more duration.  We just have to walk through both to decide.
In both our Newells with 8v92 & series 60 DD's at 500 hp we've had no problem towing a full size pickup with Rzr in the bed, about 6500#.  Total weight on the 45' with toad was about 54,000#.  So with the lesser weight of a 36' FT I'm wondering how a 350hp would perform or if I should look for a U320 with the 400-450hp.  Not concerned in the speeds but will be in the mountains and concerned mostly of having to push a smaller engine harder on the passes.  We are retired so shouldn't be on a tight schedule.
Any thoughts or experiences?
Thanks,
Forest
Title: Re: Towing performance?
Post by: John Duld on March 07, 2018, 08:49:11 pm
I think you would enjoy a Cummins M11/ISM engine.
The low end torque is great.
Title: Re: Towing performance?
Post by: jcus on March 07, 2018, 09:18:45 pm
Something else to consider for mountain driving. Your Newell was heavy, but the series 60 has 1650 ft/lbs torque.
The Foretravel 36 ft is lighter but the ISC 350 has 1050 ft/lbs.
Title: Re: Towing performance?
Post by: KenKetch on March 07, 2018, 09:22:58 pm
I am glad that I lucked into buying a 450M. I appreciate it on every mountain. It also helps when drag racing.
Title: Re: Towing performance?
Post by: MrIrishSam on March 07, 2018, 09:24:15 pm
My 2002 U295 36' has a 400hp ISL with two slides. We tow a CRV with no problems, accidentally had the CRV in Park once and never noticed the wheels weren't rotating  Thank god for fellow rv'er noticing  No problems with hills so far
I am not sure where you are getting the 350hp from
Title: Re: Towing performance?
Post by: jcus on March 07, 2018, 09:30:57 pm
My 2002 U295 36' has a 400hp ISL with two slides. We tow a CRV with no problems, accidentally had the CRV in Park once and never noticed the wheels weren't rotating  Thank god for fellow rv'er noticing  No problems with hills so far
I am not sure where you are getting the 350hp from
Believe 99 to 2001, 295 and 270's had ISC 350 engines.
Title: Re: Towing performance?
Post by: Willy White on March 07, 2018, 09:38:46 pm
I tow my GMC 4dr diesel pickup and rarely get below 50mph here in the Arizona mountains, in fact I forget it's back there.
Willy
Title: Re: Towing performance?
Post by: Roger & Susan in Home2 on March 07, 2018, 09:44:31 pm
Our 2001 36' U320 with a single slide and an ISM 450 has never given us any pause in the mountains.  Lots of mountain driving in the last three years, no problems towing a Jeep Wrangler or a Jeep Cherokee going up or down.

A smaller engine will do OK, maybe not quite as fast on the up side, maybe a bit more MPG on the flat land.  I will never regret the 450 choice or the 2001 36' U320 single slide.  Perfect for us at 5-7 months a year elsewhere.
Title: Re: Towing performance?
Post by: stevec22 on March 07, 2018, 10:53:31 pm
I have a M11, 450 hp 40' U320 and  I tow a GMC Yukon.  I have not had any issues going over several passes in southern Colorado and NW New Mexico.

Recently I drove my brother's new to him 99 U295 with a 350 Cummins, towing the Yukon back from Ajo AZ.  We didn't have any issues, although we were a little slower on the on ramps and passing other trucks.  I never felt underpowered.

My advise would be to look for a U320 with the M11, but if a nice rig with the smaller 350hp cummins happens by, don't let the motor keep you from buying it.
Title: Re: Towing performance?
Post by: bbeane on March 07, 2018, 11:50:11 pm
We have a 99 40' 295 with an ISC350, scale weight 31,000 towing a Jeep Wrangler 4dr about 4600 lbs. it's not a rocket going up hill but we get there all over the west. A u320 would be nice, but I wouldn't pass up a nice 295.
Title: Re: Towing performance?
Post by: Chuck & Jeannie on March 07, 2018, 11:59:46 pm
"Too Much Torque!" said no motorhome driver, ever.
Title: Re: Towing performance?
Post by: Caflashbob on March 08, 2018, 12:08:25 am
Never had a single repeat customer that did not opt for a bigger engine on their next purchase.  But we were in the West.  Rockies.

If you pull up,to an intersection with a single car in the right hand lane and the left lane empty in your car do you move over to the empty lane if you csn as a matter  of course or do you sit behind the right lane car without even noticing the left lane was empty?

Fool proof test for if the bigger engine is needed for your next coach....
Title: Re: Towing performance?
Post by: jcus on March 08, 2018, 12:11:14 am
"Too Much Torque!" said no motorhome driver, ever.
Or  "I can't handle this much horsepower!!"
Title: Re: Towing performance?
Post by: tpboj on March 08, 2018, 07:31:43 am
We have a 2001 295 with the ISC 350 and tow a 9k lb enclosed trailer. It does the job fine as long as you are not in a hurry. I do at times wish I had the ISM.
Title: Re: Towing performance?
Post by: Tim Fiedler on March 08, 2018, 07:45:59 am
Horsepower is like money. You can do fine with what you have, more is better, and once you have it you had to lose it
Title: Re: Towing performance?
Post by: Michaelhayley on March 08, 2018, 08:30:24 am
We love our 450 ISM ...especially when merging on onramps and when in No. Carolina. We tow a Honda Odyssey at 4400 lbs and don't notice it. Although I confess I've never driven any other engine.
Title: Re: Towing performance?
Post by: turbojack on March 08, 2018, 08:59:23 am
I tow a tahoe and have not had a problem towing with the 325 HP in my 36'. I travel alot with friend that has 450HP in a 45' Entregra. We are about even when it comes to performance.  He is a little better then me on fuel mileage, except when we get in the mountains then I smoke him in mileage.  I like to travel when I can around 70 mph

Someone posted a while ago how the different weights and HP react to each other rolling down the road.  Was pretty interesting seeing the different amounts of HP needed to go down the highway.  Not sure who posted, or what to search for.
Title: Re: Towing performance?
Post by: Caflashbob on March 08, 2018, 09:08:36 am
The variable speed turbo and the higher pressure fuel rail on the ISM In some 99's(?)  and up U320's seems to have more power than the earlier m11's.  If you are into this.....

As replacing the top of my M11 would be expensive I went the other way and optimized my current setup that works pretty well. 

As a salve to my hp itch it seems with everything perfect and quality lower rolling resistant tires and driving slow the mpg can be high enough to brag about a little.

I would rather have even more power and to heck with the mileage but that's not the hand I was dealt. 

The lower rpm power band in the bigger motor is a hoot to drive.  Torque up grades stuff.  Habit forming
Title: Re: Towing performance?
Post by: jcus on March 08, 2018, 09:24:51 am
I tow a tahoe and have not had a problem towing with the 325 HP in my 36'. I travel alot with friend that has 450HP in a 45' Entregra. We are about even when it comes to performance.  He is a little better then me on fuel mileage, except when we get in the mountains then I smoke him in mileage.  I like to travel when I can around 70 mph

Someone posted a while ago how the different weights and HP react to each other rolling down the road.  Was pretty interesting seeing the different amounts of HP needed to go down the highway.  Not sure who posted, or what to search for.
Think Brett Wolfe had something to do with making this:
 https://www.rvtechlibrary.com/engine/Cat_RV_Performance.pdf

***Understanding Coach /RV Performance*** (http://forum.dieselrvclub.org/index.php/topic,6594.0.html)
and download understanding coach performance
Title: Re: Towing performance?
Post by: Pierce & Gaylie Stewart on March 08, 2018, 10:24:51 am
We don't notice the RAV4 much at about 2990 lbs behind our 36' U300 with 350hp. A six speed would be just great but the Jake does a superb job coming down grades for coach and toad.

So, we have 9 liters compared to the 8.3 in the Cummins. More cubic inches mean more low end torque and torque is king on the hills. So given the choice, I would look for the 10.8 liter M11 engine. Fuel mileage will be about the same.

Pierce
Title: Re: Towing performance?
Post by: Ted & Karen on March 08, 2018, 11:19:33 am
We have lived full time in our 2001 U270 with the ISC350 engine for over 10 years.  At one time I was pulling a loaded cargo van over 7000# and we got everywhere we wanted to.  It pulls my Subaru Outback now just fine.  Use your gears in the mountains to keep the  rpm's up and let it do it's thing. 

Cya down the road    ^.^d
Title: Re: Towing performance?
Post by: qcj on March 08, 2018, 12:42:47 pm
Forest, the 350 has twice the torque of what you are driving now.  My ISL 400 pulls my 5700 pound Dodge pickup with no problem.
Title: Re: Towing performance?
Post by: folivier on March 08, 2018, 12:44:08 pm
Chappell have you pulled your new truck with yours yet?
Which engine does yours have?
Thanks,
Forest
Title: Re: Towing performance?
Post by: RvTrvlr on March 08, 2018, 01:02:03 pm
I have the "bigger" caterpillar and when traveling with my friends with two u270s (a 34 and 36) with the smaller 8.3 cummins (rated 25hp less, but huge torque difference) I noticed with all of us using cruise control I would pull far ahead of them going up hills. The huge bump in torque from the larger engine meant I could pull up hills without downshifting or losing speed that would slow them down or require a downshift.

Of course all of us are happy with the performance we have. I would be happy with either engine.
Title: Re: Towing performance?
Post by: Chris m lang on March 08, 2018, 09:08:03 pm
We've decided that a 36' is what we are looking for.  Haven't decided on whether we want a slide in front or not.  We've had both in our Newells so understand the differences and issues.  Won't be full timing but will take trips of a couple months or more duration.  We just have to walk through both to decide.
In both our Newells with 8v92 & series 60 DD's at 500 hp we've had no problem towing a full size pickup with Rzr in the bed, about 6500#.  Total weight on the 45' with toad was about 54,000#.  So with the lesser weight of a 36' FT I'm wondering how a 350hp would perform or if I should look for a U320 with the 400-450hp.  Not concerned in the speeds but will be in the mountains and concerned mostly of having to push a smaller engine harder on the passes.  We are retired so shouldn't be on a tight schedule.
Any thoughts or experiences?
Thanks,
Forest

Another thing you may want to consider the M11 has a 4000 series Allison which will accept 565 hp and 1770 ft lb torque (according to Allison brochure) and the 8.3  has the 3000 series Allison which will accept 370 hp with 1100 ft lb torque.  You could probably get more hp out of the 8.3 but I would be concerned  with putting too much load on the transmission
Chris