Standard 4 vs Duallys

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Old 01-10-2009, 01:49 AM
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Question Standard 4 vs Duallys

Im not sure if this will be in the right section or not.. so if not could someone move it to the right one?

Ive always wondered how much more hauling/towing weight does having dually's support over the standard 4?

Ive always thought that Dually's support more bed weight than the standard 4 wheeled trucks.. but have never been able to find out how much of a difference weight wise that is... figure they also help with a little better traction too..
 
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Old 01-10-2009, 08:46 AM
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Last time I checked there is only like a 500 pound difference between standard 4 and dually. I think duallys are preferred in the interest of stability and safety.
 
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Old 01-10-2009, 10:46 AM
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The main difference and the easiest to verify with a visual inspection comes in the rear axle. SRW trucks use a Sterling 10.5" ring gear axle, with either 35 spline 1.5" (F250) and 37 spline 1.57"(F350) shafts. The duallys use a Dana 80 with an 11.25 inch ring gear (DRW F350 and pre-2008 F450) or a Dana S110 with an 11.80 inch ring gear (post 2008 F450).

The result is that the larger differentials can be geared much lower and still retain their strength due to the larger ring gear. The 10.5" ring gear can actually break it you gear to low (past ~5:1) and put a lot of power through it, just because of how the teeth are spaced and how the pinion stresses it. The larger axles can come as low as 4.88 stock (or they used to at least, pre 2008), which drastically changes how the truck pulls under heavy loads. Plus the larger/ stronger shafts are less prone to breakage, and in general, the axles components are proportionally larger (brakes, flanges, tube thickness, etc).

Starting with the F450, the truck is also beefed up with larger/ heavier springs, brakes, wheels, frames( starting with the 550 or the 650?), and so on, which 1) increases the box capacity and thus the pin weight for bed mounted hitches, 2) tows better since the truck is heavier, and 3) are generally geared much lower and the engines are detuned compared to 3/4 and 1 ton trucks to give a better low end pull for heavy loads.


Max payloads for the 2008 SDs can be found here: https://www.ford-trucks.com/specs/20...er-duty-1.html
The F450 maxs out at 6,120#, the 350 DRW at 5,790#, the 350 SRW at 4,350#, ad the 250 at 3,240#.
Remember all these numbers are based on facotry-specs, certain cab/ box combos, some safety fudging for liability purposes, and assume common sense being applied to loading the truck.
 

Last edited by texastech_diesel; 01-10-2009 at 10:56 AM. Reason: I keen spelle, i larned how to et skool
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Old 01-10-2009, 12:54 PM
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Duallies can usually hold LESS weight, only because the axles weigh more. Te difference is only 400lbs with the older (1999-2007) trucks, but it is there. Most people prefer them due to stability issues. You definately notice a smother ride while towing larger trailers at highway speeds. Less rocking and more solid feel.
 
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Old 01-10-2009, 01:15 PM
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One other minus (or so I'm told) is that the duellies have less traction in the snow, (less weight per tire), but with a 4X4 or 4X6 it should't be too much of an issue.

If you are going to get a truck camper, you need jack brackets to clear the larger stance of the rear end. But you will enjoy the added stability.
 
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Old 01-10-2009, 01:21 PM
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nahh if i get a camper its either gonna be a Goose neck or standard tow behind types..
 
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Old 01-10-2009, 04:44 PM
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Originally Posted by grafekie
Duallies can usually hold LESS weight, only because the axles weigh more. Te difference is only 400lbs with the older (1999-2007) trucks, but it is there. Most people prefer them due to stability issues. You definately notice a smother ride while towing larger trailers at highway speeds. Less rocking and more solid feel.
Gotta disagree with 'ya here. Check the link to the Ford payload specs for '09. The difference between a DRW and SRW F-350 is about 1200 lbs. in favor of the dually. Now when it comes to the tow ratings, a DRW and SRW with the same rear gear ratio is lots of times within a couple hundred pounds. However, for payload capacity i.e. weight supported in bed, the DRW trumps the SRW.

Ford Trucks: Super Duty 2009 Cargo Box & Exterior Dimensions. | Ford Vehicles
 
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Old 01-10-2009, 04:50 PM
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Originally Posted by Spamjohnson
One other minus (or so I'm told) is that the duellies have less traction in the snow,
ironically ive heard that before too.. but personally have a hard time believing it... but same time can see why too.. sometimes i wonder if its just the type of tire theyre using too...
 
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Old 01-10-2009, 04:53 PM
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The tire selection in a possible problem. Never owned a dually but several friends have them. One guy in particular said that the biggest problem he has had in the snow is snow packing up between the duals acting like a big drag slick and not cutting down through the snow to better traction surface.
 
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Old 01-10-2009, 05:00 PM
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Originally Posted by powerstroke72
The tire selection in a possible problem. Never owned a dually but several friends have them. One guy in particular said that the biggest problem he has had in the snow is snow packing up between the duals acting like a big drag slick and not cutting down through the snow to better traction surface.
weird... never would of thought of that as a reason.. was thinking more along the lines of it packing in the lugs like ive seen it do on every day cars...
 
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Old 01-10-2009, 08:35 PM
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Originally Posted by grafekie
Duallies can usually hold LESS weight, only because the axles weigh more.
This is completely untrue

I don't understand why people assume that just because Ford came up with a GVWR or a GCWR, that a heavier truck can handle less of a payload than a lighter one. If it's made with bigger parts, heavier parts, stronger parts, etc, then it should be able to handle more.
 
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Old 01-10-2009, 10:01 PM
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There is frequently confusion where people think a dually can TOW more than an SRW, whereas they actually tow a hair less, due to the increased weight of the larger axle. However, duallies do have a significantly larger rated PAYLOAD than SRW's. Also, stability is much improved with heavy loads and in particular, tall trailers.

Duallies also have more traction on dry pavement, but less in mud and snow. There's also the problem that snow/mud will pack in between the wheels so you have to knock it out before travelling at highway speeds or the wheels vibrate a lot.
 
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Old 01-10-2009, 10:33 PM
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Originally Posted by BareBones
There is frequently confusion where people think a dually can TOW more than an SRW, whereas they actually tow a hair less, due to the increased weight of the larger axle. However, duallies do have a significantly larger rated PAYLOAD than SRW's. Also, stability is much improved with heavy loads and in particular, tall trailers.

Duallies also have more traction on dry pavement, but less in mud and snow. There's also the problem that snow/mud will pack in between the wheels so you have to knock it out before travelling at highway speeds or the wheels vibrate a lot.
I agree completely. The only real exceptions to what you said about the towing capacity would be the F-350 DRW with the Tow Boss package and the F-450 pickup and those are due largely in part to the 4.30 gears in the Tow Boss and the larger rear axle, etc. in the F-450.
 
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Old 01-11-2009, 01:02 PM
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i'll add two cons for a dually. in new york your tolls will cost you more, and tire replacement. you'll need to buy six not four.good luck.
 
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Old 01-11-2009, 01:10 PM
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ive already pretty much written off the 6 tires things... thats a given when buying a dually itll cost me more... so i expect that one..

why is it gonna cost more at the tolls? last time i went through a toll they counted axles not the tires...
 


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