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Old 11-10-2011, 09:34 AM   #41
JRTJH
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Quote:
Originally Posted by SteveC7010 View Post
I poked around the Dodge site some more and found a lot more numbers. Took some looking.

The engine must not be the limiting factor as the 4500 and 5500 chassis and cab products use the same 6.7L diesel. The numbers just keep on climbing there. I suspect tranny and drive train limit what they can pull, with axles and suspension defining payload.
Yeah, It took some serious looking to find it on the Dodge site. I finally got to the Dodge Truck Builder's part which is an interactive PDF file. Very VERY informative. It would be nice if Ford and GM offered something similar. Hmm Maybe they do and I just haven't found it yet???

Anyway, you're probably onto something with the limitations. Otherwise, the truck components look pretty similar for such dramatic differences in payload and GVW to have identical GCWR.
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Old 11-10-2011, 06:40 PM   #42
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We may be confusing 5th wheel and trailer towing capacity (and I haven't helped ). With a 5th wheel payload capacity is very important and the DRW will have much higher capacity because of the additional tires, which usually are the limiting factor where payload is concerned. But for trailer towing payload rating isn't usually that important (as long as you can handle the tongue weight) and the SRW may be better choice. I have even seen configurations where a SRW model had a higher GCWR than a duallie simply because the SRW truck was lighter, leaving more towing capacity. Some say that the dual rear wheels add some stability and that is probably true, but also probably not enough reason in itself to go DRW if you don't need it otherwise.

If all you are concerned with is trailer towing then once you can handle the tongue weight and GCWR then what's left is drivetrain durability. You do not want to subject the drivetrain to more stress than it was designed for or you will shorten life and break things, and towing is particularly hard because the extra power is needed on a continuous basis. If you are within the rated GCWR and frontal area rating then you are techically OK, but the more stout the drivetrain the more reliable it will be and the longer it will last. Lastly, the curb weight of a Ford 1/2-ton truck is around 4600 lbs. and a 3/4 or 1-ton SRW diesel is around 7200 lbs. Don't think that doesn't make a difference in a condition where your rig is trying to decide who is in control, trailer or truck.
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Old 11-10-2011, 07:12 PM   #43
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The cab and chassis 4500 and 5500 Dodge uses a Aisin automatic transmission compared to the 68RFE. They are also using larger rearends.

Ironically, they are only 305 hp compared to 350 hp for the 2500 and 3500 series trucks.

The ratings are very confusing. Once you get into the 4.10 gear option, then the tow ratings go way up. The SRW is rated for 24K lbs and the DRW goes from 25,700 up to 30K lbs combined.

The trailer weights that you listed are for manual transmission equipped. Even the highest rating is only 14K lbs. I believe the low ratings for all manuals are due to the weak factory clutch.

Jason
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Old 11-10-2011, 08:08 PM   #44
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Quote:
Originally Posted by RCrawler View Post
The cab and chassis 4500 and 5500 Dodge uses a Aisin automatic transmission compared to the 68RFE. They are also using larger rearends.

Ironically, they are only 305 hp compared to 350 hp for the 2500 and 3500 series trucks.

The ratings are very confusing. Once you get into the 4.10 gear option, then the tow ratings go way up. The SRW is rated for 24K lbs and the DRW goes from 25,700 up to 30K lbs combined.

The trailer weights that you listed are for manual transmission equipped. Even the highest rating is only 14K lbs. I believe the low ratings for all manuals are due to the weak factory clutch.

Jason
I don't think the AI SIN Transmission is the key to the 4500/5500 tow ratings. The 3500 with 6 speed automatic is rated
Towing+:22,750 lbs - max
Payload+:5,180 lbs - max
GCWR+:30,100 lbs - max

and the 5500 with AI SIN is rated:
Towing+:22,200 lbs - max
Payload+:11,758 lbs - max
GCWR+:30,000 lbs - max

Payload in the 5500 doubles, towing goes down 550 lbs and GCWR actually goes down 100 lbs. In Dodge, apparently "bigger isn't better"

Other than increased payload, the specs are actually more accommodating for the 3500 dually over the 5500.

The listed rear gear ratio for the 5500 at those ratings is 4.88 and for the 3500 is 4.10. That could be explained by the increased HP rating in the 3500 as you said.

It looks like if you can accommodate your pin weight with the 3500, it is rated to pull as well as the 5500... ?????
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Old 11-10-2011, 08:19 PM   #45
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Steering Problem?

I am probably missing something in these latest posts but not sure how SRW, DRW, 4500 and 5500 fit into the topic of this thread..... "Advantages and Disadvantages of Towing with a 1/2T and with a 3/4T". Earlier on in this thread, I did admit that I could be "opening a new can of worms" by suggesting this new thread. Seems like the can has definitely been opened. Is there any way we can steer this can back on track? Thanks.
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Old 11-10-2011, 08:33 PM   #46
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Festus 2,

Done deal, even the 3500 isn't included in the title LOL
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Old 11-10-2011, 08:34 PM   #47
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some info to get this thread back on target:

http://www.caravanandmotorhomebooks....s_complete.pdf
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Old 11-12-2011, 04:13 PM   #48
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Incidental information:

We just completed over 1700 miles of the start of our winter sabbatical, pulling our 2011 321RES with a ½ ton Toyota Tundra. We pulled from Birch Bay, WA to Scottsdale, AZ, with stops in Cannon Beach, Medford, Stockton, Barstow and Kingman. We pulled through three 4000+ foot passes, and several 3000+ passes also. We pulled our TT dry, but it was loaded for a multi-month extended stay in Arizona. While I haven’t weighed the Tundra or TT, I estimate we were very near the GCWR for combined truck and trailer.

The Tundra is a 2007 5.7 crew-cab model with TRD off-road package still on the original tires. I installed Air Lift rear airbags, compressor and a Prodigy brake controller. I used a no-name basic 1000# weight bearing hitch, with no additional sway-control. Tow Haul mode was engaged and the transmission was kept in auto. The automatic downhill engine braking works fantastic, it easily keeps the vehicle under 65 mph with only light brake applications on 5-7% grades. I targeted 60 mph, but saw periods of 70 and as slow as 45 near the top of Mt. Shasta (note: the speed limit for 3+ axles/trailers in Cali is 55 mph). There was 6” of snow on the ground at the top of the pass near Medford. We suffered two periods of extended 30 mph crosswinds and never experienced a doubt about controllability. At one point, following a Bounder class-A pulling a small SUV through a particularly windy section, we watched nervously as he struggled to keep it on the road.

The ride ranged from fantastic to unbearable. Over the atrocious Cali roads around Stockton and Bakersfield we slowed to 50 mph several times to preserve the integrity of our TT. For the majority of the trip the ride was good (road conditions being the primary factor). We found 40 psi in the bags seemed to work best. Under-tow gas mileage averaged 11.1 for the trip, with the best leg (flat) at 11.8 and worst (mountainous) leg at 10.1 mpg.

I was somewhat apprehensive prior to starting this trip, especially after reading the horror stories and preaching’s of the ¾ & 1 ton owners posted here. While I have over 10K miles logged pulling trailers over 5000 pounds, this is our first TT. However, after completing this trip I am very pleased with the performance of our Tundra. While I can’t speak for any domestic brand ½ ton truck, the Tundra is more than adequate for a 35’, 10K pound class TT. I have no idea how much of a safety margin we had, but I never encountered a white-knuckle situation.

P.S. If Toyota were to put a diesel in this truck...

P.P.S. Time to soak up some AZ sun…
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