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Topic: Detroit Diesel Engine verses Cummings 300 (Read 1153 times) previous topic - next topic

Detroit Diesel Engine verses Cummings 300

We are now looking for a new coach to pull our 20ft trailer/studio.  We have found a 40ft., 1994 Foretravel with a Detroit Diesel engine.  We also are looking at other Foretravels with the Cummings 300. Which is better for pulling our 20ft. (car carrier) trailer/studio and why? 
Randy Woodward and Susan MorrisonWoodward
Our home base and gallery are in Eureka Springs a lovely Victorian Village in the heart of the Ozark Mountains

Re: Detroit Desiel Engine verses Cummings 300

Reply #1 –
Everyone has their favorite. All are good engines but I love 2 cycle Detroits. Have driven them since the 1970's. I did hundreds of cold starts to maximum first gear RPM in less than 20 seconds and they came back for more. If the transmission makes a early downshift, they can go almost a 1000 rpm over redline without coming apart. Fuel mileage is close on all engines.

Jake brake works well here in the west, Important if towing. Foolproof and saves a huge bill if the retarder in others has problems.
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Detroit Diesel Engine verses Cummings 300

Reply #2 –
Thanks for your information.  We feel good about this coach and especially this engine. We are not sure yet about the jake brakes, we'll be finding out about them tomorrow.  but hopefully they will be on this one.

My husband Randy started RV'ing in the early seventies also.  We got into it as a couple in the late eighties.  I am an artist and they are great for our travel etc. 

The generator has 3300 hours on it and Randy wonders if this might be a concern and this one has the air bags.  Is there anything to look for with those?


Randy Woodward and Susan MorrisonWoodward
Our home base and gallery are in Eureka Springs a lovely Victorian Village in the heart of the Ozark Mountains

Re: Detroit Diesel Engine verses Cummings 300

Reply #3 –
If you are going to haul a 20' trailer, I am assuming the weight will be well over 5000 lbs. Taking that into consideration, I would not have any 40 footer with less than the 350 hp. I probably would have the same hp minimum even on a 36 foot coach.

I like the Jake break because it puts no strain on the transmission and is still adequate for slowing the coach on steep grades. Repairs, if required, are much less expensive than on a retarder.

Also, keep in mind that the Grand Villas are lighter in weight than the Unicoach. If I were considering a Bus type coach, my minimum would be 400 hp. IMHO
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Detroit Diesel Engine verses Cummings 300

Reply #4 –
Quote from: Susan Morrison –
My husband Randy started RV'ing in the early seventies also.  We got into it as a couple in the late eighties.  I am an artist and they are great for our travel etc.

Susan,

There are a couple of our members who haul a large-ish trailer; at least one that might be along the lines of what you're thinking.  Jon Twork (1996 36' U270, which is 300 hp Cummins, I believe) with a 24 ft. enclosed trailer and Mike Baldacchino (1997 40' U320, 400 hp) with a 25 ft. car hauler.  Hopefully one of them will see the discussion or you might PM them (Mike hasn't been on the board for a few weeks) and get their first-hand feedback.

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Detroit Diesel Engine verses Cummings 300

Reply #5 –
The air bags are a real plus. They may look worn on the exterior but are really thick and don't often need changing. They are about $137/each best price and can be changed pretty quickly on the coach you are looking at. 3300 hours is quite a few but with scheduled oil changes, it may have a lot of life left. That number of hours would indicate to me that they used it a lot for camping rather than RV parks. Betting 150,000 to 170,000 miles on the rig but could be way off depending on use.

You should look underneath and check for corrosion and study the bulkhead separation issue. Easy to fix but don't want to wait too long. What state was home base? Winter road salt states are usually bad news. Lots of corrosion is a disqualifier. How many hours are on the engine hour meter in the engine compartment? You can raise the dash, and get a mechanic to flip the engine and transmission switches and check for stored codes that might indicate a previous problem. Does it have records of lub, oil changes, etc? This engine requires Delo 100 SAE 40 for maximum life (that should be longer than yours). You should go out with another Foretravel owner on a test drive as they can (probably) tell right away if it has any issues. Self leveling system is very complex but not hard to work on. These are all excellent motorhomes but none are trouble free. I have had only minor things to fix, mostly fun stuff.

Have someone check the roof for cracks. They will indicate it was stored outside for most all of it's life. How are the decals. They are also a good indicator of storage. Very expensive to replace and painting is better/less expensive option. How old are the tires? Regardless of tread left, age is a factor here. Both airs work off generator? How about the fridge? Original? Figure about $1K for a new one.

It is a buyer's market now but you should have a Foretravel person look at it with you.

If you can, post high resolution photos of top, bottom, inside etc. You could upload to Picasa or another photo site and then post here with a link to the photos.  We could all comment then. Especially important if you can't get a member to look at it in person.
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Detroit Diesel Engine verses Cummings 300

Reply #6 –
motorhomes_pulling_trailers-owner@yahoogroups.com

These fine people will answer all your questions.  Jon Twork is the moderator.

Hope this helps.
We are only strangers until we meet; however, some of us are stranger than others

Re: Detroit Diesel Engine verses Cummings 300

Reply #7 –
If you plan to pull more than 5,000#, be sure to check the towing capacity and tongue weight capacity for the coach. I think many of the older coaches are rated to tow 5,000# weight with no more than 500# on the tongue.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Detroit Diesel Engine verses Cummings 300

Reply #8 –
I am a Detroit Diesel fan, however I would prefer the Cummins C Series along with the Retarder. First, the Jake Brake on a 6 cylinder Detroit is not all that effective compared to the Retarder. Next the Cummins will have better, cheaper life costs.
Detroit Diesel 2 cycle mechanics are getting very few and far between.
Only the military can get a new 2 cycle Detroit, all others have been shipped to Mexico etc. They were not allowed to be made in the USA since 2000. Only the Govt can get them now.
This is my opinion.
For what is is worth FWIW

Re: Detroit Diesel Engine verses Cummings 300

Reply #9 –
Dave,

Agree with your assessment.

Will add that MPG will be lower for a DD two stroke vs modern 4 stroke turbo, inter-cooled diesel such as the Cummins C.

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Detroit Diesel Engine verses Cummings 300

Reply #10 –
If it's a U300 with the 6V92 it with have a Jake or (rarely) a trans retarder.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Detroit Diesel Engine verses Cummings 300

Reply #11 –
It was either 99 or 00 that they "up'd" the towing cap to 10K. Before that it was 5K.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Detroit Diesel Engine verses Cummings 300

Reply #12 –
Quote from: Dave M –
I am a Detroit Diesel fan, however I would prefer the Cummins C Series along with the Retarder. First, the Jake Brake on a 6 cylinder Detroit is not all that effective compared to the Retarder. Next the Cummins will have better, cheaper life costs.
Detroit Diesel 2 cycle mechanics are getting very few and far between.
Only the military can get a new 2 cycle Detroit, all others have been shipped to Mexico etc. They were not allowed to be made in the USA since 2000. Only the Govt can get them now.
This is my opinion.
For what is is worth FWIW

Dave,

The DD Series 60 3 stage jake provides up to 400hp of stopping power. Do you know what stopping power a retarder typically provides?

david brady
'02 Blue Bird Wanderlodge LXi
David Brady
Asheville, NC
2004 Prevost H3 Vantare
2002 Wanderlodge LXi (sold)

Re: Detroit Diesel Engine verses Cummings 300

Reply #13 –
Quote from: travelite –

The DD Series 60 3 stage jake provides up to 400hp of stopping power. Do you know what stopping power a retarder typically provides?

david brady
'02 Blue Bird Wanderlodge LXi

The 60 series is a modern 4 stroke and totally unrelated to any DD used in a Foretravel.

All DD's used in Foretravels were well before the  introduction of the 60 series and are the "old technology" 2 stroke DD.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Detroit Diesel Engine verses Cummings 300

Reply #14 –
David, I read the Retarder has 2000 ft lb torque worth of retarding, that is more than the new ISX 650 HP @ 1950 ft lb. output,  The ISX is very effective on power.

From the seat of the ole pants, the 2 cycle 8V-92 Jake is not anywhere near as effective, not even on the 12V71.  My pants vote for the Retarder.  Besides for the 2 cycle to be very effective you need to gear it so the RPM is up on the governor limits.
Have played those games, can assure nothing sounds like a 12V-71 in a tunnel, you can actually make traffic stop in the tunnel, guess it scared em silly, I loved it  ;D

Re: Detroit Diesel Engine verses Cummings 300

Reply #15 –
Great info, thanks Dave. I had no idea the retarder was that effective, of course, you do need to watch the heat. I'd really like to have both a retarder and a jake. A retarder for those restricted zones and for the entire state of California! What's pretty cool about my jake is the turbo boost I get when it's engaged. I've seen as high as 20psi boost on the jake; hence, the 400hp of stopping power.

Thanks Brett, I'm still learning the common engine configurations that Foretravel used over the years.

david brady
'02 blue bird wanderlodge, lxi
David Brady
Asheville, NC
2004 Prevost H3 Vantare
2002 Wanderlodge LXi (sold)

Re: Detroit Diesel Engine verses Cummings 300

Reply #16 –
Keep reading how ineffective the retarder is but we do live in the mountains in California and use the retarder constantly while driving in nothing but steep grades. It works well with our RAV4 toad and I can't imagine the need for anything more. Have driven with retarders before and they provide even better braking but have to watch the trans temps. I lay off where "no Jakes" posted but it is just not that loud with the stock muffler. Foretravel disc brakes also do the job well and I don't believe in letting the retarder/Jake do all the work. That is what the brake pedal is for. Have used it in 10% plus approaches to Yellowstone and all through the west without a wish for anything better. Effective at all RPMs but is at it's best as RPMs build.
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Detroit Diesel Engine verses Cummings 300

Reply #17 –
I don't think there is any doubt that a Transmission Retarder is a great addition to any coach. It is much more useful than the Jake while driving in heavy traffic but they are expensive to fix and maintain, cost of extra Transynd, and under slippery conditions can cause loss of control of the coach if you are not very careful. In my opinion where and how you drive dictates which system is better for the individual driver.

If my primary use is for long, downhill runs in the mountains, I like the Jake as it won't overheat. For slippery roads I like the Jake since because it is not quite as effective as the Transmission Retarder and will not cause the rear end to skid. If I am driving frequently in heavy traffic, I like the Transmission Retarder for supplemental braking in emergency situations. The Transmission Retarders do reduce service break wear in everyday driving but considering the low miles typically driven in a motorhome, I doubt that the added cost of maintaining the retarder offsets the savings on service breaks.

The bottom line is a Jake vs a Transmission Retarder should not be a deal breaker for the average driver. The transmission retarder is not even used by most other brands but it is one very nice addition if it is on the Foretravel you wish to buy. If I could have had the choice of a Transmission Retarder or a Jake on my coach I would pick the Transmission Retarder but the Jake will do everything I really need it to do so I am satisfied.

One other point, the Jake on my coach with stock muffler is not noisy enough to be of concern at average rpms in posted areas. I leave mine on much of the time.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback
 

Re: Detroit Diesel Engine verses Cummings 300

Reply #18 –
  ^.^d Well said Kent, I agree with your findings and I have a similar coach..... I have used a transmission retarder on my Bluebird coach, it worked well however had minor overheat problems when driving in continuous mountains/hills.... (really had to watch the temperature) .  Up hill creates heat and Down hill creates heat...  :o
The selected media item is not currently available.
Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake