Increasing Towable Weight

[rsbilledwards]

Alright, here is my question for a discussion. Phrasing this is going to be difficult. All of the MH builders have a maximum given towing weight, lets say for reference 5,000 pounds. I am not referencing tongue weight here only towing weight. Why is this not different for cars being towed and utilizing their hydraulic disc brakes versus a trailer with electric brakes? Electric brakes certainly do not have the same braking ability and are woefully inadequate. First, they are drum brakes and fade much faster than discs, Secondly, they use the face of the drum as the friction surface as opposed to the radial surface of the drum as do cars. Thirdly, setting the modulating pressure of the controller is left to the ability of the driver/operator. If the trailer brakes were converted to surge hydraulic disc brakes, which can then be tied directly to the coach's hydraulic system with a modulator, why can't the trailer weight be increased over that 5,000 pound threshold? Now remember no reference to tongue weight it is just towed weight.

My first acknowledgement to this question would be that the cross member of the hitch assembly would need to be upsized to a heavier wall thickness as would the receiver tube.

Bill

[wolfe10]

Towing capacity is determines by the WEAKEST element in the motorhome.

Yes, it could be brakes, but could be transmission, frame or frame extension, etc.

And, it is my understanding (could be mistaken) that for all chassis makers/RV manufacturers the capacity assumes that the towed weight will have brakes.

[rsbilledwards]

Brett,

I would concur that the assumption would be that all have brakes. That said, are not hydraulic brakes significantly better than electric brakes generally used on trailers which are at least in my mind the weakest point if adding towing weight. Yes the hitch could be as well, but assuming it is not the weakest link.

Thanks

Bill

[wildebill308]

I think the only practical way to increase how much that you can tow is to buy a coach with enough towing capacity to begin with. There may be numerous things that in theory might improve capacity but you don't know what the weak link is on your coach.

Bill

[rsbilledwards]

Ok, then allow me to add another element to the equation. The coach assumes no additional weight other than the towed weight.

Bill, I think there are some generic actions by manufacturers that cover their behinds. This is for my information and someone else that has structural knowledge might benefit or not. There is brain power here to draw on. So being specific to the coach, mine, the Panther. With the added power, and structural changes, weight limit went up 2,000 pounds total, hitch and tow weight remained the same, same hitch. The rear chassis is not constructed like the Zanzibar at all. The C ([) channel has been doubled to accommodate the C12 CAT, both in weight and torque capacities. There is little doubt in my mind that the hitch assembly is the same on both coaches thereby placing a stated limitation of 500 tongue weight and 5000 tow. By increasing the size/thickness of the cross member bar of the hitch assembly and the receiver it should be able to safely tow a greater load. I am not intending to tow an additional 5,000 pounds or looking to tow 10,000 on the hitch but possibly 2,000 making a total of 7,000 or less. Now remember no added tongue weight. The C12 has 125 more horses and nearly double the torque of the 3126B. It is not the weak link. I am ok with you guys being the devil's advocate. I need the input to determine how to design the changes. I look at my 03 Ford Super Duty dually and it has a greater capacity and everything is smaller except the hitch assembly.

Thanks

B

[manholt]

Bill.

In your sig you mention a Featherlite and toys. Do you tow it behind DP or the 03' Super Duty? Are you trying to tow the trailer and toys by DP? I see what you got, but I don't really know why you posted the "pull" question! Also the brake question!

What is the length of your DP and do you have a tag?

Carl

[blakeloke]

Bill E,

You might get a fab shop to engineer, build and certify the hitch. Doing so may be helpful for insurance claims, safety inspections and potential new owner.

Remember the rule. Tongue weight should be 10% of gross trailer weight. Anything less and you run the risk of the trailer wagging in the rear.

Blake

[five]

Lots of information on this thread. This has been posted before, but here's the bottom line:

Tow rating is the lower of:

1. Coach's hitch rating.

2. Coach tow rating.

3. Chassis tow rating (sometimes different than the coach's).

4. The difference in weight between the coach's GCWR and the coach's actual weight when ready to tow.

[manholt]

That took care of towing! Now, on to original question by OP, brakes....?

Carl

[wolfe10]

Clearly not all brakes are created equal. That goes for cars, truck, motorhomes as well as trailers.

And, having owned several coaches over the last 2 decades, I can attest to the differences. Have had air drum with exhaust brake at one extreme and current coach with hydraulic over hydraulic fixed caliper disk brakes (4 piston) with ABS and 2 stage engine compression brake at the other extreme.

But, I have not seen towing ratings differ based on type of brakes.

[rsbilledwards]

It amazes me how folks do not read the entire question. Not that you did not but I said in each posting there is NO TONGUE WEIGHT only PULL WEIGHT in this situation and now the reason, I am using a Trailer Toad, Trailertoad.com. I am doing this because I don't want the tongue weight applied to the back of the coach. The website makes perfect sense to me. All of the hard jars, irregular roads the 500 pounds becomes a lot more when physics are added to the tail of the coach. The Panther has a long tail and a heavy engine. Hence the Trailer Toad and the interest in strengthening the pure "pull" capabilities of the hitch. If the trailer has hydraulic brakes "disc" capable of stopping its own weight the coach is only activating those and is not doing the stopping or slowing of the trailer, the trailer is doing that. The reason for the comparison of electric over hydraulic drum or disc, is that electric are really inadequate in any situation or barely so. Discs are far superior to either of the others and will readily stop a load with out fade. Manufacturers are not going to differentiate any variances between braking systems and will apply a generic rating covering the weakest link.

The real issue here just brought up, would be verifying the structural integrity of the modified or redesigned or newly designed hitch. For me building the hitch is not an issue, Certifying it could be. I added the dually as an example only of something w/less power, smaller chassis, less braking ability, greater capacity X2. Yes I haul the feather lite with both. The Panther is as Brett described, Hydraulic over hydraulic fixed caliper 4 piston Disc w/ABS and C12 with a 2 stage Jake, not an exhaust brake. It will throw everything off the counter under heavy braking no problem.

The axel location on the 24' Feather Lite allows for a greater than five hundred pounds tongue weight when the car and ATV are loaded. The over all increase in weight is under the 2000 pound example.

Carl, I tried to send you a personal note and your mail slot is apparently full and the coach does not have a tag axel. It is an 8 air bag suspension, it is not a BF Goodrich Velvet Ride.

Thanks, I appreciate the input,

Bill

[casuall454]

Hitch "pull capacity" have you looked at DMI hitches ? We use them for pulling gravity wagons = no tongue weight how ever the units with bin extensions can weigh 6 to 13 tons.

So now back to your question on "certified hitch" for weight pulled, with no tongue weight. Here is the base unit, you would have to work with DMI on flange adapters. Or consider a local custom vehicle fabrication shop, they can fab adapters to your coach frame rails.

Hope this is of assistance.

http://www.reese-hitches.com/products/DMI_Quic_n_Easy_Trailer_Hitch_Receiver_,47070007

[manholt]

Casuall454.

Good looking Jeep! Anybody who has a happy dog, is on my "good" list ! Maybe wrong, but your Entegra has a 20K hitch!

Bill. I have had Staker trailers before, hauled "cigarette boats" ! Hit me over the head with a 2x4, why do you need certification? To me, your "weakest link" is the long tail. I would think that the chassis manufacturer would have compensated for that and the weight off the engine, so if you can pull 5K then you should have no problem with 7K....look at what goes down the Interstate, being pulled by Class C and A's....scary! If your trying to get re certified on your coach GVWR, good luck! You'll have a better chance repealing Obama Care!

Carl

[kaypsmith]

By nature, if you increase the pull weight dynamics of a hitch, the tongue weight capabilities will increase also. Whether you use that factor or not is purely a choice that is yours. The trailer toad appears to be a good idea for reducing the extra weight added to your chassis. But I believe that the coach manufacturer does need to be the one with the final say as to how much pull weight that anyone's coach is capable of pulling for safety reasons.

For instance if you are only pulling in Florida or any other state that is reasonably flat, you probably can get by with pulling some extra load, but the engineer that designed your coach is compelled to take into consideration all factors, such as 7% and sometimes

even greater slopes.

With all this said, I believe that the manufacturer of the coach, and the manufacturer of the trailer toad should be posed with your questions for obvious reasons. The weakest link will always be there unless you know for sure what that may be, and make necessary adjustments to correct them, not saying that it can't be done, but there are too many factors to just guess. Only you will know for sure when you come across an unsafe situation, and can decide whether to go there or not.

Enjoy your motorhome and enjoy all the beauty that you encounter on your many journeys.

[rsbilledwards]

Thank you for all the input, just what I expected or had hoped for. I think Carl hit it on the nose. Certifying the coach virtually impossible for the additional tow weight. Using the DMI hitch probably overkill but what the heck it will be different and likely a one off combined with the Trailer Toad, a smooth pull. Yes the coach manufacturer did do some weight compensation by moving the Onan 7.5 genset to the front of the coach. Power is not an issue with the C12 CAT and the 4060 Allison. Both of them were designed for a lot heavier duty than this lite weight coach at 31,000 pounds. The C12 I am told, loves the mountains. We went this past weekend to Oregon and see what we bought in the Safari Panther. We drove it and oh my, we were not disappointed. With only 11,781 on the odo it is a real barn find. We will go back in April and pick it up for the drive back to Denver...Wheee

I towed this same Featherlite trailer, 3,300 pounds around with a 3,300 pound Porsche and a Trail 90 in it, summer of 2014 with the Zanzibar and a 3126 CAT. It was a bit slow going up some of the hills and did not over heat in 5,200 miles of Northwest mountain driving including some for sure 7+% climbs. Fuel consumption was around 8.5 and 6.5 to the gallon. I found it necessary to drive further ahead than I normally would have. The trailer currently has electric barely there brakes and I will convert to hydraulic discs and the M&G set up to do the trailer braking. I make this last comment loosely and let it reflect on the construction of these older coaches, not the newer ones. 1998 coaches had a lot less engineering in them, and a lot more trial and error beings as they were built early in the development of the coaching industry. We can pick the fly stuff out of the pepper all day about this, but the best part of this experiment is using common sense along with modern technology and learned fabrication skills to achieve a given goal with out getting into the big pile of ....

Again Thanks

Bill

[garyreed]

Had to Google the trailer toad to wrap my head around the OP's idea. After viewing the YouTube videos, I can see where they might have a practical use. it looks like a lot of extra wearable parts to maintain to gain a couple thousand pounds. Your coach is set up right with the C-12 and never dreamed, if I read the post correctly, it would have hydraulic brakes.

I did like a previous poster suggesting some fabrication on the hitch to make it safe. If the goal is to lighten the tongue weight could you add an axle to the trailer if the load inside cannot be adjusted. In the toad video it looked like a lot of side to side stress on the hitch while backing up or cornering.

As far as the hydraulic surge brakes vs electric trailer brakes, they may brake better but while researching axle upgrades for my trailer I found that some states will not recognize them because of there inability to stay locked in the event the trailer coming loose frome the tow vehicle. I will add that I have worked on trailers with electric over hydraulic and air over hydraulic which do have lockup capabilities. I am not sure how to get hydraulic power from your coach to the hydraulic trailer brakes. Also the car hydraulic verses electric trailer brakes, might be closer than you think if you account for the car not running as this is were the car gets better stopping. Have you ever tried to use the brakes without the engine running. Do those classic Porsches have brake boosters?

I too have sratched my head on how they rate towing capacities on pickups and RV's. The drive train in your coach is the same as what is pulling 80000 lbs down the road in the form of double and triple trailers with single axle trucks so I do believe the hitch may be the weaker link. I have not researched whether a higher towing capacity would require an upgraded opperators license. That may make the coach harder to sell new and who will buy an F350 if it could only pull 5000 lbs. I would rather meet you on a mountain road pulling a16000 lb trailer with your coach than with your F350.

Just some thoughts

Gary

[manholt]

Gary.

A Staker trailer, regardless of manufacturer, comes with 2 or 3 axles, depending on length/load. Mine was 34', 3 axles and held a 31' Scarab Cigarette with 2 engines, each at 640 hp! I pulled it with a 450 Centurion by Ford! This was back in 1994-2000, had I to do it over, I would have had a DP with the biggest CAT I could find.

Carl

[manholt]

Bill.

If your happy, we are all happy!

Carl

[garyreed]

I do agree with you Carl and having worked extensively on the Cat line of truck and equipment engines, the 3126 and the c12 were my favorites. The best for power vs fuel economy vs weight.

Bill do you know anyone with one of those trailer toads? Keep us posted on yours with the pro's and con's. I would like to check one out in person.

[rsbilledwards]

The Trailer Toad axel is either fixed or live, depending on direction of travel. When backing a load the axel can be locked/pined in place. Going forward and unpinned it has x nr of degrees of turning ability. I saw one last year under a goose neck trailer and it followed very nicely. I have a few more questions to ask Jock at Trailer Toad and one of those was the how many degrees does the axel rotate/turn. I am told there are about 1500 of them on the road. As for the adding an axel not practical, unfortunately, and moving the other two forward a bit same problem. Fenders and wells integral to floor and walls, 1/2 in and 1/2 out and the current position lends to a heavy tongue if front engine and car loaded first. I think it is better w/ATV in first but still do not like the additional weight on the long tail of the coach with that C12 hanging back there too.

I bought this particular coach because it did not have a bedroom slide in order to have the full integrity of the uncut side wall. I could buy a new trailer but Featherlites are pricey and building a custom one well they might take my wallet. I bought this one 10 tears old for 50% of new 5 years ago and it was still $9,500 but with most of the bells and whistles. It tows great but the back end is way back there.

With respect to trailer brake lock up, I think the M&G set up is air actuated and likely would lockup. Will see on that tomorrow and report back.

Carl, I for one would like to know more about the big hole in the water...the cig boat. I know how big my racing hole was over the years but boy was it fun.

I was just thinking about the swing ability of the DMI hitch with the Trailer Toad locked...I don't know will see and more conversation with Jock. There are several others out there where the axel is not live and behind a pickup they are pushed sideways on the tires not good!

Almost forgot to answer the most important question asked about the PORSCHE brakes...nope no booster unless you are referring to my size ten shoe. No those cars were blessed with brakes way oversized for their measly 1,800 pounds thru 1965 and all 4 corners. When Porsche introduced the 911 the same brakes were used on a car a thousand pounds heavier and still were more than adequate.

Again thank you all for the input

Bill

[garyreed]

Will your front end float when pulling the Featherlight with the extra tongue weight, and do you think the toad will stop that.

I just had one more question to ask the toad guy.

Does it have a title and will it need a license plate?

I also noted you were from Evergreen. Did you ever race those Porsches in La Junta?

Gary

[rsbilledwards]

Gary,

Towing the Featherlite with the Z, I had no noticeable front end float. The wheel base on the Panther is about a 12 inches + longer than the Z and do not expect any float. No there is no vertical tongue weight imposed by the Trailer Toad so that eliminates any possible float. There were no good pictures of the hook up of the toad but there is a stabilizer setup between the coach and toad to aid in keeping the toad square to the coach and good one on the plate, and minimal at worst but another good one to ask. I am titled in Montana.

I called M&G this morning about the brake away stopping aspect. It is not a problem. The basic system, short version has an air driven piston driven by coach air system that has valve of some sort that modulates the air pressure determined by input hydraulic brake pressure that is then applied to brake master cylinder installed on trailer. This then actuates the disc brakes on trailer. The lock up is achieved by installing small air tank on the trailer and I assume a one way valve of some sort. All in all about a thousand dollars buys real brakes, assuming discs and master are on the trailer.

I did run at La Junta many years ago 70s and 80s. It was not my favorite track though I did run a plenty at Pueblo. I ran a 1960 E production 356 Porsche Roadster that ate many a 911 thru the 90s. In Vintage Racing I was classed with the big bore cars since I was grandfathered in the club and running slicks. It was no contest as I could out brake them all and if I made it thru the corner first they could not catch me. I was a legal 1600 CC with a .040 over bore, 7800 red line and 140-150 horses and legal SCCA weight.

[garyreed]

Bill

What is the reason for plating in Montana?

My float is mostly on some of the rougher roads and if the shocks were not new I would think they needed replaced. I have used the speed bump test in the parking lot and it preforms perfect there.

As a kid in the seventies and early eighties, those were very fun to watch. The only way for me to get in was help the wrecker guy clean up after wrecks, although I don't remember having to pick up any Porsches. Seems like it was always the Corvettes during ther rally. They overlaid the track in the mid 90's, but can't remember to many races after that.

Gary

[rsbilledwards]

Gary,

Go to http://dmihitch.com/ for the hitch. looks to be a great idea. Just had a great conversation with the I think owner about this unit. tongue does not move during tow but does to hook up. Unit is 26 and an eighth long less receiver 30 inches wide for receiver type hitch weighs 143 pounds and on a pallet

You sent me the above so you know.

Jock just called and as for plating, no it does not need a plate as it is an extension of the hitch. Its mounting to the coach is ridged, no movement except in the direction of the tail of the coach. Axel has a lot of rotation somewhere between 20 and 30 degrees. Newer version greater than the on in the video. Trailer Toad 319 404 7001

[manholt]

Bill

Very interesting hitch. Not one I have seen!

Carl