Newbie with a truck and towing concern

[Cat320]

Towing is not the issue and is not a problem for any diesel pickup. Ignore the "pull fine" posts, because they all pull fine. Your concern with a 3/4 ton truck is the ability to carry the pin weight of a heavy 5th wheel and remain within the manufacturer's specs.

Also, the correct formula for towing: Tow capacity equals GCWR minus the weight of the tow vehicle when ready to tow. "Ready to tow" means loaded WITH the pin weight of the RV and everything else included.

[JeffinTD]

Originally Posted by Dmitri

Wow ! Thank you, thank you, thank you ! I really appreciate your responses and admire and respect the courtesy and professionalism in which you all display within this forum. I hope to contribute some day as well.

I am off to the dealership to get some clarfication on the specs. I'm just surprised that a 3/4 ton, Heavy Duty, diesel may not do the job for a 30 foot 5er, (rookie mistake). 1 ton SRW (GMC / Dodge) is plan "B".

Safe travels and THANKS SO MUCH!

Dmitri

Though not required for what you are doing, at least check out a dually. It will be a much more relaxed drive, even with the 30' job.

Also, everyone i know learns from their 1st RV what they really want. I never figured I'd want bigger, but that changed. If the 03 Ram I ordered new would have been a dually I'd still be driving it, and would have saved $$$.

If you go 5.9 cummins, I'd suggest stick shift if you can live w/o an auto. The 48RE auto is ok but only having 4 speeds hurts towing performance.

Later came the 68RFE someone else mentioned, which is a much better auto for towing.

[JIMNLIN]

These are not commercial vehicles, so the the rules that apply to commercial vehicles do not apply here.

0

Carrying pin weight by the vehicles manufactures certified a RAWR isn't just a commercial thing. If your a engineer then you should help yourself better understand how a truck owner with a RV or a truck owner carrying a load of concerte blocks or your commercial hauler or a owner pulling his backhoe/truck camper/ets can use the trucks RAWR/tire capacity to carry pin weight as the OP wants to do.
Your implying there are seprate axle/tire weight regs for commercial and RVs. Not so. A commercially registered truck comes under the same axle/tire limits as does a RV or any other non commercial vehicle. The only difference is a commercial vehicle may purchase higher gross to declare a higher GCW (truck and trailer). he cannot buy more axle/tire capacity.

If a truck owner chooses to use the manufactures GVWR to figure pin weights on the trucks rear axle and ignore RAWR thats fine. Its safe and it isn't illegal

If a truck owners chooses to use the manufactures RAWR to figure pin weight on the rear axle and ignore GVWR that fine. Its safe and it also isn't illegal.

[RustyJC]

Originally Posted by JIMNLIN

If a truck owner chooses to use the manufactures GVWR to figure pin weights on the trucks rear axle and ignore RAWR thats fine. Its safe and it isn't illegal

If a truck owners chooses to use the manufactures RAWR to figure pin weight on the rear axle and ignore GVWR that fine. Its safe and it also isn't illegal.

Larger commercial trucks generally have a GVWR that is the sum of the individual GAWRs - thus, the ability to interchange the ratings. That is NOT the case with most lighter duty pickups where the sum of the GAWRs is normally substantially higher than the GVWR. One reason for this could be that it's not the load carrying capability of the axles that are limiting the total weight that can be carried by the vehicle's tires (i.e., the GVWR) - it could be the vehicle's frame or the capacity of its braking system. Thus, the manufacturer's warning to exceed NEITHER the GAWRs nor the GVWR. To arbitrarily make the statement that the manufacturer's GVWR can be ignored with impunity ignores the structural and/or component performance considerations that can underlie the engineers' establishment of the vehicle's GVWR limit.

Weight regulations are generally aimed more at bridge and road loading and vehicle taxation/revenue generation and not at determination of the safety of a given vehicle/towed load configuration.

Rusty

[Coma]

First. Buy enough truck! Trying to save up front with a smaller truck will end up costing you more, don't ask me how I know.

If you have a significant other, make sure they sit in the track on a test drive. Right seat noise is waaay more expensive to fix.

The perfect truck, IMO, is a Ford interior with a Cummins hooked to a Allison 6 speed. Instead, I had a GMC, 2 Chevy's and a Ford.

Look at your trailer suspension. My travel trailer had a 7k rating. The tires added up to 7020lbs and the suspension was 2x 3500 axels. I had lots of flats till I fixed that. Make sure your tire and suspension are rated correctly. That is, actual trailer weight minus the pin weight.

You should also evaluate how you use the truck when you aren't pulling the trailer. Is it a dedicated tower and no commuting? Will it be a daily driver? A crew Cab long bed Dually is a PIA in the city, for example. 4x4 or not. Many a dry camp is simply a place to get stuck without 4 wheel drive. Also consider larger trucks. There are some med/heavy trucks that are ideal for towing heavy fivers. What it cost for a new diesel four door dually will get you a nice used med/heavy with a 100" Sleeper a super 10 spd and a CAT or a Cummins to fit.

Most of all, as mentioned earlier, is have fun.

[Bjsrv]

If given the choice a dually is the way to go. More stability and safer feel.

[JIMNLIN]

Rusty,
Weight regulations your talking about has nothing to do with this size truck. Axle/tires ratings for a 2500 truck come no where near max axle load for roads and bridges.
This from PA size and weight regs chapter 49;

(c) Gross weight.--
"No vehicle or combination shall be driven
with a gross weight in excess of the sum of the allowable axle
weights as set forth in this section, nor shall any vehicle or
combination be driven with a gross weight in excess of the sum
of the manufacturer's rated axle capacities."
PA weight regs are no different than any other state as commerce moves freely between all the states. All state regs aren't worded this clear as to the intent. My state for example simply says the legal axle limit period.

First off the vehicle manufacture certifies the 2500 trucks, in the OPs case, FAWR and RAWR. Certification per the FMVSS includes brakes/wheels/tires axles and components and suspension. The FMVSS is a minimum as the manufactures do their own testing probably for that long warranty period.
The truck manufacture may use a lower GVWR for a nice duty cycle period for advertising purposes or tax purposes or a nice long warranty period. Thats why when you buy one of these trucks and put it in commercial service generally (not all cases) the warranty period is reduced.

Also there is a email from a CA size and weight commander on a question from a RVer on another web asking ; (snip)
Q: “Many of the owners travel over their tow vehicle GVWR and /or
GCWR. Are there any state laws against this? Or does the owner just
take the risk if they wish?”

A: The California Vehicle Code (CVC) does not contain a law that
specifically limits the amount of weight a vehicle may tow based on the
towing vehicle GVWR or GCWR. There are, however, laws that limit the
amount a vehicle may tow based on other criteria.
Section 21715(b) CVC prohibits a motor vehicle under 4,000 pounds
unladen from towing any vehicle weighing 6,000 pounds or more gross
weight. This section would apply to smaller pickups and Sport Utility
Vehicles attempting to tow large trailers.
Section 1085(d) of Title 13 California Code of Regulations prohibits
the loading of tires above the maximum load rating marked on the tire,
or if unmarked the maximum load rating as specified in the applicable
Federal Motor Vehicle Safety Standard, or in a publication furnished to
the public by the tire manufacturer. This would most likely happen in
the case of a pickup truck towing a large fifth wheel travel trailer, as
those types of trailers tend to transfer a larger portion of their
weight to the last axle of the towing unit causing that axle to exceed
the tire load limits.'

The FMVSS the commander mentions says basically the tires shall match the vehicle manufactures axle ratings (GAWRs).

[RustyJC]

We seem to be talking past each other. You're hung up on commercial weight enforcement. I'm talking about the manufacturer's guidelines. I think we've both made our points. so it's up to the individual user to decide whether or not to abide by the manufacturer's ratings or not.

Rusty

[JIMNLIN]

I'm not the one hung up on commercial weight enforcement . Quite the oposite. You and TXiceman man brought up the commercial weights thing. Legal size and weight regulations doesn't mean its only a commercial issue.

Folks have used these trucks for many more years than the RV industry has been around carrying loads determined by the manufacture axle/tire capacities. Many RVers may use the manufactures GVWR to figure alxle loads. Either way is safe and legal according to DOT regs.
Other folks have their opinions and load their trucks disregarding the manufactures GAWR or GVWR.

Dmitri;
Sorry for the hyjack. Hope you learned something new about weight regs/legal issues regarding our size trucks from all the back and forth.

Your plan B sounds like a good plan especially the new GM 3500 loaded LTZ DMAX/A SRW trucks. GM raised their RAWR up to 7050 lbs and increased the tow rating to 17000 lbs and 11100 GVWR and close to 4000 lb payload according to GM weight calculator.
Owners say the ride has improved even with the weight capacity upgrades. One stout truck.
The 3500 SRW Dodge doesn't match up well with the '11 GM however some dealers say weight upgrades are comming this summer. Good luck

[JeffinTD]

Although I personally try to stay within all ratings, that wasn't the point of my posts.

Having towed the same 30' 5th wheel in the same conditions with both a 3500 SRW and a Dually, the dually is much more relaxing to tow with.

As long as I have a 5th wheel (or if I ever have a pickup camper) I will always have a dually.

I just feel more relaxed and less fatigued when I get to the camp spot, and am ready to explore, ride ATV's or whatever other activity was the purpose of the trip.

[RustyJC]

Originally Posted by JIMNLIN

I'm not the one hung up on commercial weight enforcement . Quite the oposite. You and TXiceman man brought up the commercial weights thing. Legal size and weight regulations doesn't mean its only a commercial issue.

Folks have used these trucks for many more years than the RV industry has been around carrying loads determined by the manufacture axle/tire capacities. Many RVers may use the manufactures GVWR to figure alxle loads. Either way is safe and legal according to DOT regs.
Other folks have their opinions and load their trucks disregarding the manufactures GAWR or GVWR.

No, Ken and I have come at this topic from an engineering perspective. Manufacturers establish limits. They are there for a reason. The manufacturers say don't exceed them, but the laws provide a "loophole" that some individuals use to justify ignoring some of them.

Let me give you an example to show why axle and tire ratings are not the "be-all" and "end-all" when it comes to sizing a tow vehicle. GCWR and GVWR are factors that must be considered as well.

I can take a 4 cylinder automatic Ford Ranger and stuff a Dana 60 front axle and Dana 80 DRW rear axle under it with Rickson 19.5" tire and wheel conversions with no changes to the vehicle's engine, transmission, cooling capabilities, chassis strength, etc. According to the law as you want to quote it, I can now tow heavy 5th wheels with this rig since I'm not exceeding axle and tire capacities. The fact is, however, I've done nothing to upgrade the other vehicle systems, nor have I strengthened its chassis - these considerations enter into the manufacturer's establishment of GVWR and GCWR ratings.

There are 4 manufacturer's ratings that Ken and I are saying should be considered in selecting a tow vehicle - front axle GAWR, rear axle GAWR, vehicle GVWR and vehicle GCWR. Your point seems to be that the laws only address two of these - front axle GAWR and rear axle GAWR; therefore, it's OK to ignore the other two.

Self-rationalization of a decision to tow heavy 5th wheels with a SRW 3/4 ton truck is one thing. Advocating that others do it is something else. Each user must make his/her own decision in that regard. Ken and I are merely attempting to help a potential user select a vehicle that can handle the job without exceeding the manufacturer's ratings - ALL of them. Personally, to advise a newbie to do anything else would be irresponsible on my part. YMMV, of course.

Rusty

[frankparisi]

With my 2500 '95 I pulled a 32ft 13,000lb gvwr 5er. All weights GVWR, axle + tires were within the limits according to Flying J scales.
With power increased + air bags it was OK. Stopping was scary sometimes even with an exhaust brake. If you have a choice go with a bigger truck!
My '09 2500 4:10 6spd auto with Arctic Fox 25ft 5er is fun! :-)

[RustyJC]

Just for grins, let's do some thumbnail calculations.

A 95 2500 had an 8,800 lb GVWR, right? Let's say you had a laden truck curb weight of 7,000 lbs (my 2002 2nd generation 3500 dually was 7,680 lbs, just for reference) and a pin weight of 20% of the 5th wheel's total weight with the 5th wheel loaded up somewhere near its 13,000 lb GVWR.

Laden truck curb weight (7,000 lbs) + 20% of laden 5th wheel weight (13,000 lbs x 20% = 2,600 lbs pin weight) = 9,600 lbs GVW, or 800 lbs over the 8,800 lb GVWR.

I would have thought your numbers would have put you in this vicinity.

How close are my assumptions to your scale weights and actual ratings??


Rusty

[TXiceman]

Like Rusty noted, he is a mechanical engineer and so am I. We both deal with manufacturers ratings every day and someone would have my hide if I knowling advised a customer/client to exceed the manufactures ratings.

So we both explain the numbers game and hopefully the person asking the question will educate themselves to the point that they can make a prudent decision.

Being a registered Professional Engineer, I have a Code of Ethics to follow in my engineering work and if I stray outside the code, I can suffer monetary fines plus suspension or loss of my license.

I will not argue the point any farther.

Ken