SRW vs DRW

klr650goldwing wrote:
Is there a general rule regarding how much weight is okay for SRW and how much is too much? We are thinking of a larger 5er and not sure how much larger will require a new truck too.

The rule is GVWR. You can pull more than you can carry. Once you run out of payload, that's it. Even if you could, in theory, pull more, once any one rating is busted, you're done.

Older trucks had far less payload than the newer ones. You'll find some SRW trucks with GVWRs over 11,000 pounds, where they were closer to 9k 20 years ago and 10k 10 years ago. DRWs are closer to 14k pounds, whereas they were 10k 20 years ago and 12k 10 years ago. The trucks of today are themselves a little heavier, but most of the increased GVWR has become increased payload capacity.

Just to give you some numbers about my truck so you can see how I do the calculation:
Truck unloaded vehicle weight (UVW): 7,200 (this is full of fuel, no passengers)
Truck GVWR: 9,900

Payload capcity: 9,900-7,200 = 2,700 pounds.

Trailer UVW 9,200
Trailer GVWR 13,500
Trailer pin weight empty: ~2,180

GWWR - UVW - pin weight = 520 pounds of remaining payload for me, my dog, and whoever else is in the cab.

Which shows I'm a little tight on weight for passengers and gear. Fortunately it's usually just me and the dog, with enough payload left over for a passenger. All of our gear goes in the trailer to keep us within GVWR.

DRW truck of the same year would give me another 2k pounds of GVWR. Certainly that would greatly increase the total combination weight I could have on board.

Just so you have an idea, GCWR is 23,500 for my truck. Total weight the last time I went over the scales was 16,500. That means in theory the drivetrain can pull another 7,000 pounds. Realistically, there's no way to load the truck and trailer in such a way to make that possible. While I could probably put something pretty heavy in the back of my toyhauler and have similar pin weight, I highly doubt I could get to another 7k pounds without overloading the GVWR. And in any event, My trailer's GVWR would be busted before that happened; it has 6k lb axles.

Hope this real world example helps.

klr650goldwing wrote:
Is there a general rule regarding how much weight is okay for SRW and how much is too much? We are thinking of a larger 5er and not sure how much larger will require a new truck too.

We bought a SRW F350 CC, sb,4x4,6.7 in Dec '14 and at that time had a '06 Cedar Creek Silverback 33LBTHS. Pin wt, 1800, max GVW 13,800, dry 10,800. No probs whatsoever w/ that rig. May '17, upgraded coach to a '18 Big Country 3560 SS, pin 2900, max GVW 16,000, dry 14,000. With the BC, I was over on truck's GVW and tire capacity. Wasn't too worried about the truck (bad advice I'm sure), and really didn't think much a problem w/ the tires. That was until last year and planned trip to FL during height of summer heat. Now the tire concern started to really bug me. Short story, we traded in the SRW for DRW F350 for a total peace of mind with everything regarding the tires erased now. Would we have been okay w/ a SRW.....perhaps. But just had this nagging gut feeling that wouldn't go away. Was always told "Trust your gut instincts". With the DW driving, I didn't feel 1 bit uncomfy w/ her behind the wheel. Do I miss the SRW....you betcha. Like many, do see plenty of SRW trucks towing at least 15.000 lbs + RV.

If your looking for opinions, mine is: 15,000 lb trailer and under your okay w/ a SRW. Wanna go higher....get a DRW.

Just remember one thing DRW (dual rear wheel) will NOT go through a Car/Truck Wash !!

Ivylog wrote:
You will hear that a big 5er must have DRW but on occasion I pull a 20K load with my SRW BUT I can adjust the pin weight by where I position the load on the trailer. 5er manufactures save money by putting more pin weight (often 20%) than what’s needed for good handling...10 % is enough. This lets them use smaller tires and axles than what you will find under a TT of similar GVW.

Not the greatest advice, as at 10% pin an 5er would likely chuck badly! It is also difficult to get the pin that low in a normal 5er, GN flatbed no issue, 5er RV not so much.
We just stepped up to a DRW as a future proofing step.

Every truck of every brand, SRW or DRW, has a specified payload rating. And the specified payload rating for any truck, SRW or DRW, can vary considerably depending on that particular truck configuration. Example, an F350 SRW payload rating can vary as much as 1,000 lbs depending on cab, bed, engine, tires, etc. So there is no one number for all trucks.

You will hear that a big 5er must have DRW but on occasion I pull a 20K load with my SRW BUT I can adjust the pin weight by where I position the load on the trailer. 5er manufactures save money by putting more pin weight (often 20%) than what’s needed for good handling...10 % is enough. This lets them use smaller tires and axles than what you will find under a TT of similar GVW.

Use this calculator: Calculator

Rear axle weight rating, and payload capacity are key factors. When you use the calculator the last value (Fifth wheel trailer king pin weight percentage override) will tell you what you really need to know

Since you have a specific year and model of truck it would seem that you could easily determine if it could handle the trailer you are considering. I guess out of curiosity, what is the GVW of the trailer you are looking at?

My general rule of thumb was always..... fiver over about 13,500 get a dually. Loaded pin weight should always be your guide. Of course its much more complicated than that. Duallies will be more stable when towing heavy. Duallies will cost you 50% more for tires. No answer is as pat as we would like them. Personally other than a under 30 foot fiver I would almost always opt for a dually for stability alone. But then again I dont take my fiver off road either.