Axle location question

[joshuabardwell]

I appreciate your being polite but I am indeed correct. You might want to reread your manual or look at your sticker on your hitch. If it came from the factory, I would bet it too is rated for 500-600 lbs without a weight distribution setup. I advise you to take your own advise and look up your specs.Jeff

Here is a link to the ball mount that I'm using: Ball Mount 5" Rise or 6" Drop. Note the tongue weight: 1200 lbs, 10% of the rated tow weight.

If you look at this page, you can see the towing specs for my truck: Dodge Towing Guide. Please note this text at the bottom: "However, the maximum tongue weight on Class III (The bumper ball) is limited to 500 lbs, and Class IV (The receiver hitch) to 1200 lbs." So, if I use the bumper holes, the tow rating is limited to 5000 lbs and the tongue weight to 500 lbs, just like your truck. If I use the frame-mounted receiver hitch, the tow weight is just over 13,000 lbs, and the tongue weight is 1,200 lbs. In all of these cases, the tongue weight comes in right around 10% of the tow weight.

Hitch is rated for 11500 lbs with a weight distribution draw bar and 5000 lbs without.

All you're telling me here is that you have a hitch that is specced smaller than your truck. My guess would be that you have a class III hitch (5000 lbs / 500 lbs is a typical spec for a class III hitch). Your truck can handle up to 11,500 lbs, which means that if you put a class IV hitch on it (typical spec 12,000-13,000 lbs) OR if you used a weight-distributing hitch, then you could max out your truck's towing capacity. Also, notice that on your placard, the tongue weight for both weight-distributing and non-weight-distributing is exactly 10% of the rated tow weight, which is what I'm saying.

Honestly, we could both be correct, because you say that most hitches are rated at 500 lbs tongue weight, and I would bet that most hitches you and I see are Class III. I just think it's more correct to say that the hitch tongue weight is usually about 10% of the rated tow weight and leave it to the towing person to figure out what exactly that is.

 

[jejeosborne]

Here is a link to the ball mount that I'm using: Ball Mount 5" Rise or 6" Drop. Note the tongue weight: 1200 lbs, 10% of the rated tow weight.

If you look at this page, you can see the towing specs for my truck: Dodge Towing Guide. Please note this text at the bottom: "However, the maximum tongue weight on Class III (The bumper ball) is limited to 500 lbs, and Class IV (The receiver hitch) to 1200 lbs." So, if I use the bumper holes, the tow rating is limited to 5000 lbs and the tongue weight to 500 lbs, just like your truck. If I use the frame-mounted receiver hitch, the tow weight is just over 13,000 lbs, and the tongue weight is 1,200 lbs. In all of these cases, the tongue weight comes in right around 10% of the tow weight.



All you're telling me here is that you have a hitch that is specced smaller than your truck. My guess would be that you have a class III hitch (5000 lbs / 500 lbs is a typical spec for a class III hitch). Your truck can handle up to 11,500 lbs, which means that if you put a class IV hitch on it (typical spec 12,000-13,000 lbs) OR if you used a weight-distributing hitch, then you could max out your truck's towing capacity. Also, notice that on your placard, the tongue weight for both weight-distributing and non-weight-distributing is exactly 10% of the rated tow weight, which is what I'm saying.

Honestly, we could both be correct, because you say that most hitches are rated at 500 lbs tongue weight, and I would bet that most hitches you and I see are Class III. I just think it's more correct to say that the hitch tongue weight is usually about 10% of the rated tow weight and leave it to the towing person to figure out what exactly that is.

First off I completely agree with the 10%. I will not dispute that. I also am only talking about the reciever hitch on the truck and not the ball mounts.
The picture I took is of the reciever hitch that came mounted on my truck and nothing to do with the bumper. You need to open your manual and I promise you that your hitch is also rated at 500-600 lbs without a weight distribution setup unless it has been replaced with an aftermarket hitch. My hitch which is a class IV hitch is actually rated for 200 lbs more than my truck 11,500 minus 11,300 lbs. On the link you posted, click on the "towing basics" link in the top right corner. Then select "trailer weight classes". You will see that your class IV hitch as well as most every other class IV hitch requires a weight distribution hitch for towing loads in this range (greater than 5000 lbs). You will only find this information in your manual or the hitch itself but it is there. Also please read the link I posted it will help as well.

Here is an additional link for the OP that I started a while back where I did similar axle work.
http://www.tractorbynet.com/forums/projects/237522-popup-camper-conversion-toyhauler.html
Jeff

 

[joshuabardwell]

You need to open your manual and I promise you that your hitch is also rated at 500-600 lbs without a weight distribution setup unless it has been replaced with an aftermarket hitch.

Unfortunately, my manual doesn't have towing info, and the hitch itself doesn't seem to have a placard (although I haven't gotten under the truck and looked to see if it's there). I'm pretty sure it's a factory hitch, though.

On the link you posted, click on the "towing basics" link in the top right corner. Then select "trailer weight classes". You will see that your class IV hitch as well as most every other class IV hitch requires a weight distribution hitch for towing loads in this range (greater than 5000 lbs).

As much research as I've done into towing specs for my vehicle, and I can't believe I never saw that before. That's really surprising. What that seems to be saying is that, if you don't intend to use a load-balancing hitch, there is no difference between a class III and a class IV receiver.

 

[jejeosborne]

Unfortunately, my manual doesn't have towing info, and the hitch itself doesn't seem to have a placard (although I haven't gotten under the truck and looked to see if it's there). I'm pretty sure it's a factory hitch, though.



As much research as I've done into towing specs for my vehicle, and I can't believe I never saw that before. That's really surprising. What that seems to be saying is that, if you don't intend to use a load-balancing hitch, there is no difference between a class III and a class IV receiver.

In your manual on page 294. It says:

"Equalizing hitch are required for Class III or IV trailer
hitches and tongue weights above 350 lbs (159 kg) and
use of trailer sway control is recommended.".

I was wrong, your 3/4 ton is only rated for 350 lbs and not 500-600 lbs. I am really surprised it is that low.

http://www.ramtrucks.com/en/owners/manuals/

 

[handirifle]

I bought a 3500lb complete idler axle with springs and hangers for $220 and 15" tires mounted on white steel rims for $75 each delivered to my door. Tax and shipping included from Great Wolf Trailers - Distributor of Trailer Parts, Landscape Racks, Truck Parts

The owner was very helpful and everything arrived perfect.

I will though warn you just one more time that the simple 60% rule may not work with your tractor. No room for error and 2-3 inches will make a significant change in that short of distance.

PS no attitude taken so no need to apologize but appreciate it.
Jeff

The "warning" wasn't ignored, just not acknowledged. I would like to ask how one would "adjust" the CG with a loaded trailer? I have no way to put the tractor on there as of now anyway (mentioned that in first post, sort of) and even if I did, I cannot move the axle to test your theory. So I am at a loss on how to accomplish this. The only thing I could do (if I got the tractor on there) is weigh the current tongue weight. Probably would have been a good test with the 1 3/4 pallets of sod I hauled home from Lowes, but didn't think of such a test then, hindsight I guess. As mentioned, the tractors weight is not even distributed, probably not even close the the sods distribution, being the FEL and engine are both up front, most of the 1500 (or so) is right up there.

Also, someone mentioned "the tow ratings on my truck is 5000lbs" not true, according to the owners manual, for my exact model/year/configuration, it is 6700lbs. Wasn't sure if that was just a reference number or what. I cannot find any reference on the door tags to GCWR, but GVWR is 6600lbs and rear axle is rated at 3750, don't remember front rating. It is factory tow pkg.

I do have 2000lb overload springs on the rear, and I do know the rear axle rating is based on a lot more than springs, but this does reduce some of the burden on the rear springs.

 

[joshuabardwell]

In your manual on page 294. It says:
My Ram Trucks: Ram Owners Service Manuals - Ram Cars, Minivans, SUVs

That's interesting. That's not in the manual that's in my glovebox, but I'm not the original owner of the truck, so it may not be the original manual. Thanks.

 

[joshuabardwell]

But wait... something isn't right here, because the manual shows a GVWR of 6500 lbs there, and my vehicle placard shows 9000 lbs. Also, they show GAWR of 3600 and 3900, but my vehicle placard shows 5200 and 6010. I think we can both agree that the info printed on the placard on the door of the vehicle is 100% authoritative. The manual's information is not matching up with my truck's info. Those specs seem to match more closely with a 1500, and I wonder whether they use the same manual for a 1500 and a 2500.

EDIT: Yeah. I just downloaded the manual for a 2005 Ram 1500, and it has the exact same info in it.

 

[jejeosborne]

The "warning" wasn't ignored, just not acknowledged. I would like to ask how one would "adjust" the CG with a loaded trailer? I have no way to put the tractor on there as of now anyway (mentioned that in first post, sort of) and even if I did, I cannot move the axle to test your theory. So I am at a loss on how to accomplish this. The only thing I could do (if I got the tractor on there) is weigh the current tongue .

I mentioned how I would do it earlier and also linked a thread on how I did it. Wait until your trailer is ready for the tractor and put it on it then. I think you are making it more difficult than necessary. Just take your time.
Jeff

 

[jejeosborne]

But wait... something isn't right here, because the manual shows a GVWR of 6500 lbs there, and my vehicle placard shows 9000 lbs. Also, they show GAWR of 3600 and 3900, but my vehicle placard shows 5200 and 6010. I think we can both agree that the info printed on the placard on the door of the vehicle is 100% authoritative. The manual's information is not matching up with my truck's info. Those specs seem to match more closely with a 1500, and I wonder whether they use the same manual for a 1500 and a 2500.

EDIT: Yeah. I just downloaded the manual for a 2005 Ram 1500, and it has the exact same info in it.

I am confused. What are your hitch limits? Please post and put my mind at ease.

 

[joshuabardwell]

I am confused. What are your hitch limits? Please post and put my mind at ease.

Well, I'm confused as well, so we are in good company! My hitch is rated for 12,000 lbs tow capacity and 1,200 lbs tongue weight. But it seems pretty clear to me now that everybody specs hitches based on a weight-distributing system being in place. The question that is outstanding is at what point you have to put the WD system on, and I don't have a straight answer for you.

One could argue that Dodge puts the exact same Class IV hitch on the 1500 as the 2500, in which case the 350 lbs TW number that is in the manual could be correct. The Dodge web site says 500 lbs TW (5000 lbs trailer weight) for a WD system. I'm not sure which of these numbers is correct.

Bottom line is that my towing capacity is substantially lower than I thought it was this morning, because I didn't realize that every hitch manufacturer (it seems) specs their hitches based on the WD rating. I bought a 12,000 lb ball mount in order to match my hitch's rating, but it sure seems like it was a waste of money, since I can't go over 5000 (or maybe as low as 3500) lbs without a WD system.

Live and learn...

EDIT: Now you have got me wondering. I am going to go out (in the rain, nonetheless!) and look under my truck to see if I can find that sticker.

EDIT #2: Sorry. I just went out with a flashlight and looked all over it, and I just don't see that sticker anywhere on the hitch.

 

[henretty]

Good rule of thumb and starting point is to put the axle at 60% the way ack from the front of the bed. This way you end up with the bed of the trailer with a 60/40 divide.

Chris

I have built many a trailer and before reading the above post was sayin to myself...60% of total trailer in front of axles 40% behind... long way of sayin he is right .......one mans opinion ....i could be wrong

 

[zzvyb6]

I'd forget about all the hitch discussion items if you are still using mobile home tires. Because, that's causing the problem you are having. Mobile home tire have very low cornering stiffness (sidebite). Therefore the trailer yaws (turns relative to the truck) in order to generate enough sideforce to handle the turns. Mobile home tires are NOT designed or intended for long haul purposes. They are never intended to be used with a one axle trailer. Even the wheels are not intended for heavy cornering. Verticle load, yes, sideload no. Mobile homes usually have TWO or MORE axles with a wide axle span (distance between wheel centers). This tends to give them higher yaw stability for their limited sidebite.

I would replace the axle with a real trailer axle using automotive type wheels and good, name brand trailer or passenger vehicle tires. Want even better high speed stability? Add a second axle. The pairs of tires add a very substantial amount of yaw/speed stability AND load capacity. Besides that, the low to very low tongue weight makes it a lot easier to maneuver the rig around the barnyard with lawn mowers, golf carts and 4 wheelers. Best setup could be dual axle, deck over, 10" trailer tires. That's what I use. Sometimes the tongue weight is negative but she's good for 80 mph.

BTW, all my recommendations are based on a 40 year career in Vehicle Dynamics at a major auto company. Whenever we measured the handling capacity of mobile home tires and wheels (usually for a lawsuit), we vowed never to use them even for a pond float. HOWZ zat?

So now let all the anecdotes begin about how they are using mobile homes tars on them dirt track rice cars. Sit in a courtroom with a case against a vehicle manufacturer by the wife of a vegetable sitting in front of you who swore them tars was good and you will have had a life changing experience.

Remember that they usually sit for 10 years between use, wheels don't have a safety bead, and are the main reason someone ALWAYS is following them when they get kicked out of the park (I mean neighborhood). And you thought it was because its a 'wide load'. Its actually pretty wide wallowing all over two lanes. And the tow vehicle has enough rear tire on it to haul locomotives to a shop. They use enough tongue weight to keep a super model from getting wet from all the drool....

 

[zzvyb6]

Here's one of my haulers: zero or low tongue weight (rear diff ground clearance).

 

[jejeosborne]

Well, I'm confused as well, so we are in good company! My hitch is rated for 12,000 lbs tow capacity and 1,200 lbs tongue weight. But it seems pretty clear to me now that everybody specs hitches based on a weight-distributing system being in place. The question that is outstanding is at what point you have to put the WD system on, and I don't have a straight answer for you.

One could argue that Dodge puts the exact same Class IV hitch on the 1500 as the 2500, in which case the 350 lbs TW number that is in the manual could be correct. The Dodge web site says 500 lbs TW (5000 lbs trailer weight) for a WD system. I'm not sure which of these numbers is correct.

Bottom line is that my towing capacity is substantially lower than I thought it was this morning, because I didn't realize that every hitch manufacturer (it seems) specs their hitches based on the WD rating. I bought a 12,000 lb ball mount in order to match my hitch's rating, but it sure seems like it was a waste of money, since I can't go over 5000 (or maybe as low as 3500) lbs without a WD system.

Live and learn...

EDIT: Now you have got me wondering. I am going to go out (in the rain, nonetheless!) and look under my truck to see if I can find that sticker.

EDIT #2: Sorry. I just went out with a flashlight and looked all over it, and I just don't see that sticker anywhere on the hitch.

I would think that you could use the 500/5000 lb rating and be safe. Sorry I didn't see the PM before asking. A WD hitch torques the ball mount in the reciever tube which allows all of the bolts attaching it to the frame to carry the load. Without the WD hitch, all the load is carried on the rear most bolts so I see why the rating differences. Glad to clear the air and maybe keep you from a failure.
Jeff

 

[joshuabardwell]

Glad to clear the air and maybe keep you from a failure.
Jeff

Likewise. I hardly ever get my trailer over 5000 lbs, but my tractor would put it right at 5100, and if I had an implement on, that would be extra. Would I get away with it? Probably. There's a lot of safety margin built into this stuff. Would I be comfortable doing it? Heck no. Especially since, if I get in an accident, I'm going to be crucified if I'm not squeaky-clean.

All these conversations about towing just make me cringe, when I think of people I've known who have loaded up trailers with god-knows how much weight, hitched them up to a system rated for who-knows-what, and blithely started off down the road. I knew one guy who bent an axle after he and nine of his friends piled into his mini-bus for a week at Burning Man, including ALL OF THEIR WATER (approximately 900 lbs of water). It was his father-in-law's trailer, to boot! Halfway through the trip, they blew a tire because it was riding on the sidewall. Halfway back, they blew the new tire, and that was when they figured out something was wrong :laughing: Nobody died, but sheesh... it's not like what he did is that unusual.

Let's see... he bent the axle on a dually trailer. That was probably a 3500 lb axle. So perhaps he had 7000 lbs plus GTW. And I guarantee you it wasn't a WD hitch. Ugh. I guess it just goes to show how over-engineered these things really are, that it held together and got everybody home in one piece.

 

[handirifle]

I'd forget about all the hitch discussion items if you are still using mobile home tires. Because, that's causing the problem you are having. Mobile home tire have very low cornering stiffness (sidebite). Therefore the trailer yaws (turns relative to the truck) in order to generate enough sideforce to handle the turns. Mobile home tires are NOT designed or intended for long haul purposes. They are never intended to be used with a one axle trailer. Even the wheels are not intended for heavy cornering. Verticle load, yes, sideload no. Mobile homes usually have TWO or MORE axles with a wide axle span (distance between wheel centers). This tends to give them higher yaw stability for their limited sidebite.

I would replace the axle with a real trailer axle using automotive type wheels and good, name brand trailer or passenger vehicle tires. Want even better high speed stability? Add a second axle. The pairs of tires add a very substantial amount of yaw/speed stability AND load capacity. Besides that, the low to very low tongue weight makes it a lot easier to maneuver the rig around the barnyard with lawn mowers, golf carts and 4 wheelers. Best setup could be dual axle, deck over, 10" trailer tires. That's what I use. Sometimes the tongue weight is negative but she's good for 80 mph.

BTW, all my recommendations are based on a 40 year career in Vehicle Dynamics at a major auto company. Whenever we measured the handling capacity of mobile home tires and wheels (usually for a lawsuit), we vowed never to use them even for a pond float. HOWZ zat?

So now let all the anecdotes begin about how they are using mobile homes tars on them dirt track rice cars. Sit in a courtroom with a case against a vehicle manufacturer by the wife of a vegetable sitting in front of you who swore them tars was good and you will have had a life changing experience.

Remember that they usually sit for 10 years between use, wheels don't have a safety bead, and are the main reason someone ALWAYS is following them when they get kicked out of the park (I mean neighborhood). And you thought it was because its a 'wide load'. Its actually pretty wide wallowing all over two lanes. And the tow vehicle has enough rear tire on it to haul locomotives to a shop. They use enough tongue weight to keep a super model from getting wet from all the drool....

While I cannot compete with your background, I can say that when I can lift the front with two fingers, I know it is not right. This was a farm trailer, and I can tell you that 10" wheels would most likely bend under the weight of the trailer alone. It has an 4x8ft bed, and the entire trailer is built from 1/4" thick, 2" x 4" box tubing. My driveway to my workshop has only a SLIGHT uphill grade to it and I cannot even come close to pushing the trailer up that slope. As for the tires themselves, you might be right, these particular tires ARE DOT rated, but they are mobil axles and wheels.

I intend to change them out when $$$ permits. Right now it does not. I changed this trailer from farm to highway, and it was inspected and signed off by the CA DMV before registering it for highway use, so liability issues are arguable at least.

 

[jejeosborne]

I'd forget about all the hitch discussion items if you are still using mobile home tires. Because, that's causing the problem you are having. Mobile home tire have very low cornering stiffness (sidebite). Therefore the trailer yaws (turns relative to the truck) in order to generate enough sideforce to handle the turns. Mobile home tires are NOT designed or intended for long haul purposes. They are never intended to be used with a one axle trailer. Even the wheels are not intended for heavy cornering. Verticle load, yes, sideload no. Mobile homes usually have TWO or MORE axles with a wide axle span (distance between wheel centers). This tends to give them higher yaw stability for their limited sidebite.

I would replace the axle with a real trailer axle using automotive type wheels and good, name brand trailer or passenger vehicle tires. Want even better high speed stability? Add a second axle. The pairs of tires add a very substantial amount of yaw/speed stability AND load capacity. Besides that, the low to very low tongue weight makes it a lot easier to maneuver the rig around the barnyard with lawn mowers, golf carts and 4 wheelers. Best setup could be dual axle, deck over, 10" trailer tires. That's what I use. Sometimes the tongue weight is negative but she's good for 80 mph.

BTW, all my recommendations are based on a 40 year career in Vehicle Dynamics at a major auto company. Whenever we measured the handling capacity of mobile home tires and wheels (usually for a lawsuit), we vowed never to use them even for a pond float. HOWZ zat?

So now let all the anecdotes begin about how they are using mobile homes tars on them dirt track rice cars. Sit in a courtroom with a case against a vehicle manufacturer by the wife of a vegetable sitting in front of you who swore them tars was good and you will have had a life changing experience.

Remember that they usually sit for 10 years between use, wheels don't have a safety bead, and are the main reason someone ALWAYS is following them when they get kicked out of the park (I mean neighborhood). And you thought it was because its a 'wide load'. Its actually pretty wide wallowing all over two lanes. And the tow vehicle has enough rear tire on it to haul locomotives to a shop. They use enough tongue weight to keep a super model from getting wet from all the drool....

Well I was just telling myself, this guy must be nuts. Then you posted the pictures and solidified my thoughts. You consider yourself an expert and come on here to educate people who are new to trailers and towing that negative tongue weight is not an issue. I think you swept floors for 40 years or were only hired by defendants who got into towing accidents. Yeah, I am sure a tandem axle 8 foot trailer is a good idea but come on.

 

[zzvyb6]

A 20.5 x 8.00-10" tire load range E has a max rating of 1650 lbs. 4 of them should give you plenty of load capacity, stability, peace of mind and a low deck height. A neighbor has these on a 4 x 8 trailer for hauling roofing bundles. That's what is on that hay trailer. (Its 8 x 16')

I am a professional engineer, worked for the defendents against all kinds of vehicle misuse, and sweep my outside floors with a leaf blower. Inside, I have 2 Dysans.I have analyzed trailer towing with my own and other compuer simulations, measured all kinds of tires on an MTS Flat-Trac tester, and performed handling tests on the road and on laboratory equipment at a Proving Grounds. And some U.S. patents on these methods, BTW. I bale hay with a 15 year old tractor using a mower and baler that's almost as old as I am. I restore old water pumping metal windmills for fun and preservation. Many of them having come from Kendallville, Indiana. For fun, I shoot a Barrett M99 50 BMG. If you have an opinion based on facts bring it on. If you read it in Reader's Digest (a Carolyn Davis recipe, maybe?) keep it to yourself and then do some homework.

Sort of jives with JDGreen227's recent post, eh? Since I know WHY a positive tongue load is usually recommended, I can compensate for that need in other ways. What's in your wallet?

 

[jejeosborne]

A 20.5 x 8.00-10" tire load range E has a max rating of 1650 lbs. 4 of them should give you plenty of load capacity, stability, peace of mind and a low deck height. A neighbor has these on a 4 x 8 trailer for hauling roofing bundles. That's what is on that hay trailer. (Its 8 x 16')

I am a professional engineer, worked for the defendents against all kinds of vehicle misuse, and sweep my outside floors with a leaf blower. Inside, I have 2 Dysans.I have analyzed trailer towing with my own and other compuer simulations, measured all kinds of tires on an MTS Flat-Trac tester, and performed handling tests on the road and on laboratory equipment at a Proving Grounds. And some U.S. patents on these methods, BTW. I bale hay with a 15 year old tractor using a mower and baler that's almost as old as I am. I restore old water pumping metal windmills for fun and preservation. Many of them having come from Kendallville, Indiana. For fun, I shoot a Barrett M99 50 BMG. If you have an opinion based on facts bring it on. If you read it in Reader's Digest (a Carolyn Davis recipe, maybe?) keep it to yourself and then do some homework.

Sort of jives with JDGreen227's recent post, eh? Since I know WHY a positive tongue load is usually recommended, I can compensate for that need in other ways. What's in your wallet?

Please tell us how you compensate using "other ways" to make a negative tongue weight trailer safe at 80 mph on 10" wheels. What speed are those tires rated for? Never seen a trailer tire being rated over 65 mph let alone a tiny 10" tire spinning almost twice as fast as a 15 inch tire.

 

[joshuabardwell]

Well I was just telling myself, this guy must be nuts. Then you posted the pictures and solidified my thoughts.

I ain't no expert (as my contributions to this thread will clearly illustrate), but I also cringed when I saw those pics.