How to stop rear axle bounce

[thecatsfan]

You are correct. I shouldn't state anything in absolutes.

But I disagree that a GCWR in the manual is a defined weight rating. It is a manufacturer's recommendation. My manual also has a recommended max trailer weight and combined rating. It is not on the legally recognized weight tags affixed to the vehicle, and, at least in any state I have lived in, which is only a few, cannot be enforced as a weiht limitation on the truck.

Does your truck have the GCWR affixed to the vehicle from the manufaturer, or does it only appearin the manual?

Also, the code you mentioned in the Texas CDL manual again is specifically used only in regards to the determination of commercial vs non-commercial vehicles - nothing more! That same determination is valid here in Colorado as well, but it has absolutely no bearing on private vehicles driven by private citizens for private use. That has been tested here in court.

[RustyJC]

Quote:

Originally Posted by thecatsfan You are correct. I shouldn't state anything in absolutes. But I disagree that a GCWR in the manual is a defined weight rating. It is a manufacturer's recommendation.

GCWR = Gross Combination Weight Rating - that's what's in the manual. The manufacturer calls it a rating, not a suggestion or recommendation, so that works for me.

Quote:

Originally Posted by thecatsfan Also, the code you mentioned in the Texas CDL manual again is specifically used only in regards to the determination of commercial vs non-commercial vehicles - nothing more! That same determination is valid here in Colorado as well, but it has absolutely no bearing on private vehicles driven by private citizens for private use. That has been tested here in court.

The definitions in Section 521.001 (which are those in Section 522.003) apply to non-commercial driver license classifications, not commercial versus non-commercial vehicle classifications. To wit:

Quote:

SUBCHAPTER D. CLASSIFICATION OF DRIVER'S LICENSES Sec. 521.081. CLASS A LICENSE. A Class A driver's license authorizes the holder of the license to operate: (1) a vehicle with a gross vehicle weight rating of 26,001 pounds or more; or (2) a combination of vehicles that has a gross combination weight rating of 26,001 pounds or more, if the gross vehicle weight rating of any vehicle or vehicles in tow is more than 10,000 pounds. Acts 1995, 74th Leg., ch. 165, Sec. 1, eff. Sept. 1, 1995. Sec. 521.082. CLASS B LICENSE. (a) A Class B driver's license authorizes the holder of the license to operate: (1) a vehicle with a gross vehicle weight rating that is more than 26,000 pounds; (2) a vehicle with a gross vehicle weight rating of 26,000 pounds or more towing: (A) a vehicle, other than a farm trailer, with a gross vehicle weight rating that is not more than 10,000 pounds; or (B) a farm trailer with a gross vehicle weight rating that is not more than 20,000 pounds; and (3) a bus with a seating capacity of 24 passengers or more. (b) For the purposes of Subsection (a)(3), seating capacity is computed in accordance with Section 502.162, except that the operator's seat is included in the computation. Acts 1995, 74th Leg., ch. 165, Sec. 1, eff. Sept. 1, 1995. Sec. 521.083. CLASS C LICENSE. A Class C driver's license authorizes the holder of the license to operate: (1) a vehicle or combination of vehicles not described by Section 521.081 or 521.082; and (2) a vehicle with a gross vehicle weight rating of less than 26,001 pounds towing a farm trailer with a gross vehicle weight rating that is not more than 20,000 pounds. Acts 1995, 74th Leg., ch. 165, Sec. 1, eff. Sept. 1, 1995.

The provision in Section 521.081(2) for a Class A non-commercial license (GCWR = 26,001 lbs or more) is reflected in many of the manufacturers' GCWR ratings that have models that top out at 26,000 lbs in order to stay below this breakover point.

Rusty

[450Donn]

And still the bottom line to this whole discussion is:
People are determined to use the smallest possible vehicle to pull/drag/tow/haul the largest possible load.
While it makes no sense to me and a lot of others, people will continue to insist on getting a 3/4 ton pickup and then hitching a 14 or 15K pound fiver behind it and then wonder when things break, tires fail, and no one has any compassion for their plight!
sorry, if you are firmly convinced that you are right and the rest of us are wrong, please do not ask the question. If you genuinely are interested in proper loading and how to safely load a truck. Or how much a truck can safely handle, and traverse the highways, please ask BEFORE you spend your hard earned dollars on something that is not up to the task you are asking it to do.

[Vulcangw]

Dear Catsfan,

Since this is an anonymous forum, I will choose not to get to upset with you a) effectively calling me a liar, and 2) insulting my intelligence. And I will respond just because I have time on my hands.

First, with all sincerity, I really would appreciate you or anyone else pointing me to the law that regulates weight limits on private, non-commercial vehicles. A couple of years ago, I searched far and wide through statutes in more than 20 states and could not find any law regarding weight limits on private vehicles. All the laws I found were similar, and applied to load limits on tires and axles of commercial vehicles that weigh enough to actually damage the highways. My conclusion was that the states care only about limiting damage to their roadways by 18-wheelers. Notwithstanding my inability to find state law on the issue, I have read that there really are laws governing weight limits on private vehicles. My conclusion is, therefore, that these laws must be federal laws. As of yet I have been unable to find these federal laws. I would greatly appreciate you or anyone else pointing them out to me.

Now, to respond to your insults to my veracity and intelligence. The weights I mentioned were actually state DOT scale weights. I live about 5 miles from a highway scale that has a 24/7 readout, so it is very easy for me to weigh the rig whenever I so desire. My last fiver was a Forest River Wildcat. The sticker in the kitchen cabinet said it had an unloaded weight of about 8,500 pounds. The manufacturer's website said it had a pin weight of about 1,800 pounds. I was quite amazed when I took it over the scales fully loaded and found that the loaded trailer weight was about 10,500 pounds and the pin weight came in at about 2,800. (Being both an engineering school and law school graduate, I really do believe I am competent enough to do the math that gave me those figures.) Doubt them if you will, but those are the readings. The pin weight confused me the most. I had loaded about 2,000 pounds into the trailer and half of it was added to the pin?? As confused as I was, I never worried about it because I was still under the rear GAWR of 6,084 pounds, the rig rode very nicely, and the truck and trailer set up in a very nice horizontal plane. Maybe I put too many tools, etc. in the understorage area. No matter, it rode very well.

If you really think any trailer that weighs in around 14,500 pounds should have triple axles, you need to talk to DRV (Mobile Suites, Mobile Estates), NuWa, Carriage and others who build many double axle fifth wheels with gross weight ratings well above that amount. My current fiver, a double axle Newmar Cypress, has a sticker that says its unloaded weight is 12,880 pounds. I don't recall exactly the gross weight rating on the sticker, but I believe it is just over 16,000 pounds.

When I weighed the truck and trailer and calculated the 2,800 pound pin weight of the Cypress, the truck's loaded rear axle was 5,800 pounds, and the unloaded (i.e., without trailer) weight was 3,000. Since then, I have changed to an autoslider hitch that apparently weighs about 100 pounds more than my old hitch, because my unloaded rear axle now is 3,100 pounds. I recently returned from a two week, 4,000 mile trip where the wife and I loaded the Cypress significantly more (mostly over the pin; i.e., bedroom, bathroom and understorage area) than when I first weighed it. Sad to say, I am indeed now over the rear GAWR. I weighed in both at the beginning and the end of the trip, both times recording 6,200 over the truck's rear axles (equating to a pin weight of 3,100). I am now 118 pounds over the 06 Silverado 2500HD quad cab's rear axle rating of 6,084 pounds. Am I concerned? No. Would you be concerned? Apparently so. Do I care? Not at all.

As I noted in an earlier post, the stock tires were rated at 3,042 pounds. Multiply this by two tires and you get 6,084, which is exactly the rear GAWR. What a coincidence. Would I be too far off to logically conclude that the GAWR is based on the stock tires? II talked to two different Chevy truck managers. Both told me that the only real difference between a 3500 and a 2500 HD is one leaf in each rear spring. They also told me that both trucks have the same rear axle, rated at 6,900 pounds. I am now using 10 ply rated tires rated at 3,450 pounds each for a total of 6,900 max load on the rear tires.

Yes, I have added Firestone air bags, and yes, I have changed the shocks to Rancho 9000XL adjustable shocks. As I mentioned in an earlier post, if you consider good shocks to be bandaids, then try driving your truck without any shocks. I am sure you will immediately reinstall your "bandaids". These "bandaid" shocks have virtually eliminated the harmonic bounce I was getting. And the air shocks allow me to level the truck to my satisfaction (the added 400 pounds of heavier hitch plus added pin weight would likely drop the truck slightly below level, but frankly I am not sure because I haven't loaded up without any air in the bags.

Now for braking. In my humble opinion, it is pure male bovine excrement for anyone to suggest that any Chevy pickup on the road can safely brake to a halt pulling a 10,000 pound trailer if the trailer brakes give out. Maybe Ford and/or Dodge have much larger brakes than the Chevy, but I have tried braking my last trailer, the one that weighed in loaded at 10,500 pounds, without the trailer brakes and I can tell you that the truck's brakes did a darn poor job on their own. The brakes on my Cypress are excellent, and the Prodigy controller does a very good job. I just don't see how a 3500 or a dually would stop me any better. If you are concerned that your or my trailer brakes might fail, you should be equally concerned that your truck's brakes might fail, or that your engine might fail and you will lose the power to your brakes. You also might want to worry about being struck by lightning.

Now that I got all that off my chest, let me point out that I was very pleased with how my truck and trailer performed on my 4,000 mile trip, up and down steep grades, and around twisting roads. I never once felt out of control, or that my trailer "was pushing me" all over the place, not even when I ran into extremely strong cross winds across Montana. Could I feel the wind? You bet, as I am sure I would have if I was driving my Honda Accord. But the truck and trailer still tracked straight and true.

It may be that pulling a 14,000 pound trailer with a Dodge Cummins 3500 dually instead of a Chevy Duramax 2500HD is more like driving a BMW as compared to a Honda. But just as I feel safe and happy driving my Honda, I feel equally safe and happy pulling my Cypress with my Chevy.

[Ray,IN]

There is another side of the GCWR/GVW issue. Most states sell license plates with weight limits for trucks. My truck has an 11k GWR, for which I bought 11K license plates. If I had bought 5K plates for a 1/2T pickup that is the most my K3500 could weigh and be legally driven on public roads. So, if someone wants to dodge licensing fees by plating for a lower than GVW for their vehicle they are gambling that they will never have a crash where attorneys are involved.

[Vulcangw]

Ray, our state DMV does not license pickups based on weight. I have researched state DMV laws. There is nothing in there regarding weight limits on pickup trucks. Like I said above, all the limits are based on exle and wheel weights of commercial heavy trucks.

[TEX-CTD]

great points

[Vulcangw]

I have been looking for federal law on GVWR and GAWR for pickup trucks. So far all I have found is essentially consumer protection laws; i.e., requirements for manufacturers to post their limits on/in the trucks for consumer information.

Federal Motor Vehicle Safety Standards and Regulations

Haven't found anything so far that says its "illegal" for a consumer to exceed those posted limits.

[TEX-CTD]

havent read it yet but this months issure of diesel power is about towing. might be something in there that is helpful. just got it in the mail today. well see

[wingnut60]

Don't want to get involved in what is right/legal or wrong, but I can tell you I am involved in a TX organization who lobbies for keeping machinery tags on equipment and not vehicle tags--for items that do not get driven for profit, but from site to site to work. At every meeting, the subject comes up on DOT rules, and ALWAYS there is no agreement on what they mean. We have had DOT troopers in for seminars--if it didn't impact our business so much, it would be laughable what the troopers CAN'T explain. It actually boils down to what each trooper wants to do that day, and what they want to cite us for. JP courts don't understand what the rules are, and if we want to take the time/money to drag a citation thru court, they usually are dismissed after going high enough. On the other side, we have owners who DO try to skirt the rules and we try hard to discourage that.
I have yet to run into an RVer that has been cited for anything to do with weight limits, doesn't mean it hasn't happened.

And the discussions roll on.........