Does increasing the axle ratings increase the CCC of a trailer? - RV-Dreams Community Forum

BiggarView · RV-Dreams Family Member

Does increasing the axle ratings increase the CCC of a trailer?

TRAILERKING · RV-Dreams Family Member

That's all true and fine as long as the rest of the chassis/structure is up to par that can handle the heavier axles(stiffer ride also).

The Junkman · RV-Dreams Family Member

TRAILERKING wrote:
That's all true and fine as long as the rest of the chassis/structure is up to par that can handle the heavier axles(stiffer ride also).

x2.. and tire rating

TheHarveys · RV-Dreams Family Member

I have read about some guys actually welding additional steel to the frames on their trailers to strengthen them in anticipation of adding heavier suspension, tires, etc., thus increasing their CCC.
However, everything has to be taken into consideration, like the hitch and it's mounting system. Will it handle the additional weight or will you end up pulling the hitch right off of the trailer.

Rob_Fla · RV-Dreams Family Member

Increasing Axle Ratings is like adding Air Bags to a Truck, it does not increase capacity.

In most cases frame and structure is the limiting factor in weight rating.

FastEagle · RV-Dreams Family Member

Only the vehicle manufacturer or a certified modifier can change a trailer's GVWR. The GAWR would be part of the modification. I would assume the cargo capacity would increase with a modified increase in GVWR & GAWR.

FastEagle

-- Edited by FastEagle on Saturday 26th of July 2014 11:37:57 AM

BiggarView · RV-Dreams Family Member

FastEagle wrote:
Only the vehicle manufacturer or a certified modifier can change a trailer's GVWR. The GAWR would be part of the modification. I would assume the cargo capacity would increase with a modified increase in GVWR & GAWR.

FastEagle

-- Edited by FastEagle on Saturday 26th of July 2014 11:37:57 AM

I would presume that Mor/Ryde, being in the chassis building business along with upfitting would qualify as a certified modifier. Howard's suspension upgrade journal entries don't actually mention how much they raised their trailer GVWR or CCC only that they were over weight beforehand and the suspension upfitting addressed that issue. I've also read that the IS suspension, 17.5 rims and Goodyear G114 H tires and disc brakes add approx 800lbs to a 2 axle trailer, so I expect that the net trailer CCC would hopefully increase by 1200 lbs give or take on a 2 axle trailer or 1800 lbs on a 3 axle trailer.

I have emails in to Mor/Ryde and a few 5er Mfrs to verify my hypothesis. Will report my findings.

PS: just received email from Mor/Ryde... It looks like Trailer GVWR is what it is as you say, upgrading will deal with load situations but the not legally change the numbers. The only way to do that is have it installed from the get go, apparently. cry Awaiting feedback from Mfrs to confirm. Looks like we might have to scratch a few rigs off the shortlist. confuse

-- Edited by biggaRView on Saturday 26th of July 2014 01:27:48 PM

-- Edited by biggaRView on Saturday 26th of July 2014 03:48:55 PM

Sushidog · RV-Dreams Family Member

Excellent subject! Thanks for addressing it. I wasn't aware that the GVWR on trailers was a legally enforceable number, as I have owned several trailers (utility and motorcycle,) including a home made trailer that had no data plate or ratings of any kind. How about home built designs? Wouldn't you go by axle weight ratings? Couldn't one look at the reason for the manufacturer's GVWR rather than just the numbers on a data plate? How about if the trailer had their axles replaced with lower rated ones, wouldn't the GVWR be less?

Let me give you an example of what I'm talking about. This is not a purely hypothetical discussion, as I am looking at the same model trailer manufactured over 2 different years with widely varying weight ratings, everything being the same except the axles/tires. Both the Gulfstream Conquest 295SBW and the Gulfstream Trailmaster 299SBW had a 4473 lb CCC in 2013 - making them a perfect candidate for adding a 1,000 lbs solar AC unit while still leaving sufficient CCC for fulltiming. They now have been degraded to only 2,290 lbs of CCC, eliminating the newer models from consideration, unless I can simply restore their previous CCC by a simple axle, wheel and tire upgrade. What are your thoughts on this conversion? Or should I just look for an older model?

Chip

-- Edited by Sushidog on Saturday 26th of July 2014 05:16:16 PM

The Junkman · RV-Dreams Family Member

To me weight ratings from the mfg do not mean alot. They are a guideline, with a ton of safety gap built in.

If you did up grades, on suspension / tires / Truck.. and the frame is a good one.. I would just run with the numbers of limiting factor.. period. If it makes you feel better, make a sticker and stick it on it..

FastEagle · RV-Dreams Family Member

Vehicle modifications are described in the reference below in part 567 (Certification).

http://www.gpo.gov/fdsys/search/pagedetails.action?collectionCode=CFR&searchPath=Title+49%2FSubtitle+B%2FChapter+V%2FPart+567&granuleId=CFR-2011-title49-vol6-sec571-120&packageId=CFR-2011-title49-vol6&oldPath=Title+49%2FSubtitle+B%2FChapter+V%2FPart+567&fromPageDetails=true&collapse=true&ycord=1442

FastEagle

-- Edited by FastEagle on Sunday 27th of July 2014 08:11:53 AM

BiggarView · RV-Dreams Family Member

FastEagle wrote:
Vehicle modifications are described in the reference below in part 567 (Certification).

http://www.gpo.gov/fdsys/search/pagedetails.action?collectionCode=CFR&searchPath=Title+49%2FSubtitle+B%2FChapter+V%2FPart+567&granuleId=CFR-2011-title49-vol6-sec571-120&packageId=CFR-2011-title49-vol6&oldPath=Title+49%2FSubtitle+B%2FChapter+V%2FPart+567&fromPageDetails=true&collapse=true&ycord=1442

FastEagle

-- Edited by FastEagle on Sunday 27th of July 2014 08:11:53 AM

An interesting, if not complicated read. Sections 567.4g 3 & 4 and 567.7 appear to be the important sections on this topic. Excellent resource.

Brian

MarkS · RV-Dreams Family Member

I think we may have taken an excursion from the spirit of the original question. From a commercial viewpoint, increasing the axle, wheel and tire ratings will increase your ability to carry weight. Since the capability of the frame is a function of the integration of the frame and the body, calculating that capability goes all the way back to the early stages of design of the entire unit. With that in mind we can assume that the tires and axles are the point of weakness. Im sure you are talking about increasing your total weight by 2000 pounds, or a change from 2 7000 pound axles to 2 8000 pound axles. In that case, I would feel safe carrying the increased weight. Keep your documentation showing the modification and the difference between the tag on the vehicle and your weight should be accounted for.

Remember, Lippert cant even build a frame and axles with four good brakes. So keep that in mind.

Glenn West · RV-Dreams Family Member

Most 5thers on the market, at best, marginal chassis, axles, screws, bolts (infrastructure). Just replacing axles doesn't change the rest of the equation. Few of the higher end units have a robust infrastructure that this could be achieved.

Sushidog · RV-Dreams Family Member

Thanks all.

Fast Eagle it seems that the feds are only concerned with tires, rims and axles. So upgrading the axles will comply with the law.

Mark and Glen, you both bring up a good point that if the rest of the unit is not sturdy enough adding additional axle strength is useless as now the frame becomes the weakest link. However this does not address restoring the carrying capacity of a trailer which has lower rated axles installed than they previously had.

Why would they do this, you ask? Well people are funny. Many will look at a 30ft TT with a UVW of 7,500lbs that has a GVWR of say 9,500 lbs and think that they can safely tow it with their F-150 Ecoboost with a 11,300 lb towing capacity (or 5 liter v8 with a 9,500-10,000 lb towing capacity) making it easily a 1/2 ton towable trailer in the advertisements. But if you take this same 7,500lb trailer and put heavier running gear on it upping the GVWR to 11,500 lbs then the average 1/2 ton truck owner looks at the GVWR and thinks it can't be towed by his truck as it exceeds his manufacturer's towing capacity. It's all a matter of customer perception - and that's what makes sales. I'd be surprised if Gulfstream didn't increase their sales and save money to boot by lowering the carrying capacity of their trailers. Go figure.

Chip

-- Edited by Sushidog on Sunday 27th of July 2014 04:16:40 PM

FastEagle · RV-Dreams Family Member

Most of the government regulations are directed at the vehicle manufacturers and address minimum standards the builders must adhere to. As users we are expected to stay within the design parameters the vehicle manufacturer has provided us with. In that context we can replace "weak links" with stronger ones and stay within those parameters. When we exceed the operating parameters we enter the gray area. Without guidance and certification we are surely treading on thin ice.

Here is another reference from NHTSA. Item #8 sort of addresses what this thread is about.

http://www.nhtsa.gov/cars/rules/import/faq%20site/pages/page4.html

FastEagle

-- Edited by FastEagle on Sunday 27th of July 2014 10:06:57 PM

BiggarView · RV-Dreams Family Member

Fast Eagle, that sure puts it into "lay" language. Sounds like we, the consumers, need to press the RV mfrs to improve their products with better/stronger frames, suspensions and tires seeing as so many of us are unwittingly(or knowingly in some cases) going over established GVWRs or GAWRs according to anecdotal evidence. The downside is twofold, heavier trailers will limit sales(which matters only to the Mfrs) and people will still overload trailers either unwittingly or knowingly anyway. Kind of a catch 22. Maybe these new carbon fiber constructed trailers will become the next big thing? Light weight and stronger structure.

I'm curious about what constitutes an enforcable infraction WRT exceeding GVWR or GAWR and the circumstance by which it would come into play, seeing as there is a "gray area" like you suggest. I am not looking to avoid that situation(as in circumventing or breaking rules) only trying to ascertain the best course of action in terms of trailer and equipment selection, loading best practices, etc., all with an eye toward safety for myself, family and others on the road.

--------

PS: Just received an email from Lifestyle Luxury RVs and they say that, indeed, ordering the optional heavier rated axles and tires will indeed raise the GVWR and CCC. over the base equipment. Wonder why doing it in the aftermarket by a profession installer is cause for such a convoluted process. Mark, your assessment(retaining docs for the upgrade to justify an overweight condition) seems to a commonsense approach, why cant' the regulators and the industry find a way to work the kinks out of the system?

PPS: Chris at Lifestyle tells me that an upgrade to Mor/Ryde IS with 8K axles and disc brakes with H rated tires boosts the NCC to over 4900 lbs on their LS38RS model. That's my kind of numbers smile For now, I'm going presume a similar improvement in other makes.

-- Edited by biggaRView on Monday 28th of July 2014 08:43:48 AM

The Junkman · RV-Dreams Family Member

I don't think it matters to officials what your weight cap is, how much you have loaded etc..

Many people ..Individuals.. build homemade trailers.. no specs.. Just need a vin Id added at dmv amd Bam... your on the road..

So whether you build that 35' trailer or one made from a manufacture.. Makes no real difference. Manufactures are held to a different standard than a individual.

Around here.. All they care about is the lights on the trailer, and a plate.. thats it.

So while there may be some truth to the fact only a manufacture can change ccc.. Becuase they have the sticker.. It does not mean a individual can't do it, and increase ccc.. Just do it, and save the receipts and document what was done..I would cross out the pertinent info on the tag too.. change it , if possible.. And run it..Thats what I would do..I don't think you are breaking any rules or laws.. as they do not apply to you as a individual.