Figuring CGVWR

[mopar1]

I haven't ever been able to figure out how heavy of a trailer my old truck can carry. Thought I would ask the weight police here.
My old truck is a:
1972 Dodge D200 Crew Cab 400 big block 4:10 gears
9000GVW
5560lbs front axle weight
5560lbs rear axle weight
The owners manual says "trailer weight should not exceed approximately 75% of the loaded truck weight." So is that a trailer weight of 6,750?
I have weighed the truck but I have misplaced them. I know I subtract the rating by the actual weight to get the maximum weight in the bed.

[exav8tr]

I'm not the weight police but one thing is for sure: You ain't towing a Montana, Mountaineer or Big Sky with it...... Sounds like a nice truck though. I have a niece whose husband has restored two 1970 Chevy trucks. They look real nice also....

[Art-n-Marge]

I would agree with your math that the max trailer weight is 6,750 (75% of 9,000 lbs), however this is only if the truck is fully loaded, for example, if you only load the truck to 8,000 lbs, does this mean trailer has to be lighter too, since they discuss percentage of GVWR? It may have something to do with keeping a load ratio but I don't know.

So knowing your GVWR of 9,000 and the potential of a 6,750 lb trailer your CGVWR could be less than 15,750 lbs, because combined weights tend to be less than individual weights. For example, your Gross weight rating is less than the added axle weight ratings.

On the other hand, if it's a 5er you are towing, then the trailer can be heavier, because about 18-25% of the trailer's weight is being carried on the truck's rear wheels, so you might be able to get away with an 8,000lb or heavier fifth wheel. However, you still can't exceed the RAWR or the 15,740 CGVWR. It's just that you are shifting the load to the rear (the trailer part). In any case, you cannot exceed any of the Axle weights. Then there's the side to side loading, but I won't even get into that - if you need to understand this, let us know.

For example, my truck has a 11,500 lbs GVWR and a 12,500 lb trailer weight, but only a CGVWR of 23,000 lbs (500 lbs less than the additive GVWR and trailer rating), but the 5er rating is 15,200 lbs, which means I must be careful how I load the truck bed and cab and that none of the weight exceeds my RAWR of 7,000 lbs or any of the other ratings. And none of this can exceed the CGVWR and hopefully the loads are centralized so that each side of the truck is not overloaded at any one point.

I hope this helps, but in order to understand Gross weight ratings all the other ratings must be well understood. I just went through over four months of investigating this when I increased the weight rating of my truck using certifiable methods. Believe me, there are many uncertifiable methods.

[mopar1]

Thanks for the quick replies. I guess I just need to keep loading the truck down till I can get the correct weight for the camper I want to haul? Just kidding of course.
exav8tr, I have pulled my Montana with the truck in question when I traded in the old 5th wheel. I did not know it at the time but we had the truck way overloaded. Both of the black and gray tanks were full. Plus the stuff from our old camper. It pulled real well but was short on power.
Then I bought a diesel!

[mopar1]

quote:Originally posted by Art-n-Marge

I just went through over four months of investigating this when I increased the weight rating of my truck using certifiable methods. Believe me, there are many uncertifiable methods.

Is there a post where you did this? I did not think it was possible to change the GVW of a truck or trailer that was certifiable.

[Emmel]

You are right mopar1, you cannot change the factory rating of any truck.

[HughM]

What's a certifiable method? Inquiring minds want to know.
Hugh

[Art-n-Marge]

I found out it was possible with a lot of investigation and only if you have the right combination of truck.

Mopar1 - I will provide an edit to the location of my posts where this was discussed. I learned I was not the only one that has done this.


On edit: Here's the forum post

http://www.montanaowners.com/forums/...archTerms=into

While it's certifiable because the right parts were installed, I don't plan on pursuing certification because it is not required as a private owner. You are right I cannot change the label, but after installing the right parts, and with the proper documentation I can have it certified and the correct authorities can supply the label. I just opted out to keep the costs down and I don't plan to tow others for a living.

This cannot be done with all trucks, just those that only have these slight differences. It can be done but can be a lot of work, keeping in mind more money is made in truck sales and taxes if you buy a new truck.

While my 2006 Ford F-250, PSD, Torqshift, 3.73 diff, 4x4, long bed, SRW, now physically matches a comparable F-350. I will NOT pursue certifiability because as private vehicle it is NOT required. This will also cause the DMV taxes to go up, because in my state they want more money from you if they think you are carrying heavier, even when you're not. They determine that by the VIN code (the secret 5th character that shows your weight rating).

Staying on topic Mopar1 did the right thing in buying a newer more capable truck because it never would have supported a Monty. There is a lot more factors to saying you can tow a behemoth than a strong engine.

[mopar1]

Thanks for showing me your post Art. If you decided to have your truck certified to F350 specs who would do it? Ford I would guess?
You also mention recertification is not needed because you do not tow comercially. But without it if the DOT pulled you over and you are still over the factory weight rating you still could get into trouble?

[JimF]

Don't know about your modifications but a close friend of mine took his Dodge 3500 and had it DOT certified and it IS registered for a CGVWR of 42,000. Has to stop at all the scales as it is now registered as a commercial vehicle and must comply with all DOT certifications, which it does.

[Art-n-Marge]

It is NOT Ford that redoes certification. It is contractors sanctioned by the Dept of Transportation. They might send me to Ford to get some kind of confirmation, but the the DOT company are the ones that you pay. There are a couple of companies in the Southern California I was referred to if I wanted to get this done.

If I get pulled over, it won't be for that since it's not against the law for me (and you) and the odds are great that weight would come up because that is not real obvious for us private parties. If you caused something serious by being very negligent and they can prove you were overweight I suppose that would be a different story, but how can they fault a guy for doing the work to be compliant, just not certified. Since I have all the receipts for the parts I don't expect any problems and I am no longer overweight.

JimF brings up that commercial rigs get in trouble because there is some serious tonnage involved and corporate responsibilities and they want to hold operators accountable. I guess us RVers are small potatoes in comparison and most times we don't cause accidents to others, just to ourselves when we break down. But one of these days, with enough RVers getting careless this may change. Then I'll recertify.

BTW - I actually contacted the local California Highway Patrol to seek their advice and the three officers at the desk looked at me like I was a crazy person and told me not to worry about being 1/2 ton to 1 ton over. It's the 3 tons and over they're worried about and they pointed out that only commercial companies are liable. They told me to get some airbags if I wanted to solve being overweight - I had to tell them that I already had air bags but even air bag companies will not allow going over the GVWR. Their comments were "Oh really, we didn't know that". They didn't know a lot of things it tured out, and as I left, they told me they were gonna ask around and learn what's really going on but I didn't have anything to worry about it. Obviously they weren't too concerned about it.

Lastly getting a new label will change the VIN number because the 5th character reflects the weight rating and for states that charge by weight rating will have something to go on. By not changing my pillar label I will be paying the lower original VIN taxes. So shame on me for not doing that, but it's legal.

[Emmel]

Art, you did a great job bringing your 250 up to the 350 specks, that took a lot of work and research.
You just mentioned changing the vin number, wouldn't that require another title having to be made also?
Another reason for the self satisfaction!

[richfaa]

There is a process to re certify a truck. I am not sure it required on Non Commercial vehicles. I had posted that process awhile back. I can not remember which Government entity did it NTSB, DOT?? Regarding rv's I know from having the 3400 weighed by Keystone after having the IS suspension installed which raised the axle capibilities to 7K. You are what the VIN says you are. Our VIN said 6K axles 13,975 GVWR and that is what we are..period. As far as keystone is concerned we are over weight and they have the VIN and the weight slip to prove it.

[TLightning]

quote:Originally posted by JimF

Don't know about your modifications but a close friend of mine took his Dodge 3500 and had it DOT certified and it IS registered for a CGVWR of 42,000. Has to stop at all the scales as it is now registered as a commercial vehicle and must comply with all DOT certifications, which it does.

There is a long discussion on this subject on another forum. Bottom line is the regardless of what DOT lists as your GCWR, that does not exempt you from adhering to the GCWR put on the truck by the manufacturer. The DOT wants the higher rating so they can charge a higher fee.

[richfaa]

I found the process to re certify truck/campers..But I have no idea what they are trying to say. I had saved it under Misc..I don't know why???


http://www.fmcsa.dot.gov/rules-regul...CFR571.120-S10

[HughM]

As a retired LEO, I'll agree with Rich on this one. Your are what your VIN says you are. On the side of the road with blue or red lights flashing behind you & waving receipts to the guys in uniform mean nothing.
Don't expect the LEO to crawl under the truck to verify what's on the receipts matches what's on the truck.
Hugh

[mopar1]

How about if a 1972 Dodge Crew cab had dually rear and front axles? For all intent and purposes it looked like a 1 ton but the vin called out a 3/4 ton?
Would the LEO know with something that old? I can't remember if the license registration says on it or not. That would be a dead give away.

[richfaa]

The LEO might think it was a 1 ton since it was a dually but if the registration said 3/4 ton he may conclude you are in a stolen vehicle.

[mopar1]

Then I would be going from bad to worse