Tongue Modifications that Decrease Clearance

[Justus C]

Is there a consensus on how tight an angle you should be able to make with your trailer hitched up? I'm referring to bumper pulls in this case, not 5th wheels.

For the past three evenings I have been trying to think of a way to mount a spare tire to my Hymer Touring GT. For the life of me I can't come up with any solution other than mounting it vertically in front of the battery and propane tank. This thing doesn't have clearance to mount it under the tongue; doesn't have the tongue length to side mount it; has no underbody frame to speak off for a BAL hide-a-spare; and has an integrated bumper unsuitable for mounting. I really don't want to carry it in the rear storage compartment or in our TV.

The diagram attached (not to scale!) shows a typical A-frame tongue, my pole tongue setup, and a modification I'm tossing around. It ignores the length of your hitch shank. Suffice to say every 1" that the hitch(not counting the ball) protrudes past the bumper adds about 2.5°. I'm aware of the downsides of a longer shank.

It looks like a typical A-frame tongue forms a 50° angle, allowing the TV and trailer to be oriented up to 65° apart. The limitation is the angle of the tongue. Attached is a photo of an owner modded jack-mounted spare, which would significantly reduce this angle. Is 65° an accepted industry minimum or just a standard?

My trailer has a pole tongue with a battery and propane tank. The propane tank is the larger object, projecting about 13" from the tongue. The tank limits the angle. (I know it's round; I treated it as a square for simplicity.) I calculated the max difference in orientation as 64°.

I want to add a vertical spare tire mount right in front of the battery. The spare will be 26" in diameter; on a 3" tongue, 11.5" will hang off either side. I think it will take up about 7" of tongue length. This will reduce the max orientation difference to 60°.

Outside of backing up, will I ever notice the loss of mobility? Is it dangerous or otherwise not recommended to do stuff like this?

[John in Santa Cruz]

well, both my casita 16 pulled by a tacoma, and my escape 21 pulled by an f250 can make a U turn as tight as the truck can at full steering stop.

where I get into trouble is trying to backup while in a sharp turn. With the F250/E21 combo, i simply can't get it to straighten out without going a few feet forward first. obviously, going backwards, you can make it bend more than is 'safe' and my bumper contacts the propane tank cover first.

[Raspy]

Justus,
In my opinion, most trailer tongues are too short. Often, the truck will contact the trailer body first and do some serious damage if not careful. Second, the jacks are too far forward. This means interference with the truck tailgate that can prevent one from opening the tailgate while still connected. And third, the tongue is a highly stressed part of the trailer frame. Putting two batteries, two propane tanks and then a spare tire on it adds a lot of tongue weight and stress.

Given the limitations you've identified, it seems the picture you provided is the only practical option. As John pointed out with the turning radius, there probably won't be any problem unless you need to back up to get turned around. I know I have had to back up a number of times to get turned around, and every bit of additional angle I could get was valuable. Fortunately, I can bring the truck's bumper clear over to the tongue without damage or contacting the body.

On my new trailer, I'm considering carrying the trailer spare in the bed of the truck so I can add bikes to the rear of the trailer. For me, that would be better than carrying the bikes in the truck. I know you don't want to do it, but maybe the tire in the truck will turn out to be the best plan. Just lay it flat and all the way forward. Then pile your gear on top of it. When you get home, put it away with the rest of your stuff.

[John in Santa Cruz]

I'm running an 12" towbar on my current rig, because that lets the truck tailgate drop without hitting the tongue jack. but it also gives me quite a bit more clearance in tight turns. I think its this one,
https://www.etrailer.com/Ball-Mounts/Curt/D-26.html

[Raspy]

John,

Yeah, that is an option. But clearly works best with a heavy duty truck and a relatively light trailer. If a WDH must be used, it becomes a problem.

My toy hauler had a 100 gallon water tank in the front and I had to run a WDH on my 1 ton Ram if the tank was full. I couldn't open the tailgate and I hated that. Running a longer drawbar was not in the cards with the WDH.

My friend is running a bar about 18" long to keep his bumper away from the trailer body while maneuvering. One of the first things I look at on a trailer is the tongue configuration.

[Raz]

My solution was to put the spare in the trailer under the permanent bed. While it does take up storage space, most of what I need to store is smaller and can fit elsewhere. It also has the added benefit of keeping it out of the sun.

[Daryl and Wendy]

Sacrilegious I know - but I've pretty much stopped carrying a spare for the trailer. It's been decades since I've had a blowout on the road and we are rarely more than an hour to a tire repair. Tires and roads and services and 12v compressors were different in the 60s. Today the tires are better (and I can affords better tires :-), roads still have plenty of hazards but are generally much much better, and 12v air compressors are common and affordable.

I do carry a small 12v air compressor in case of slow leaks. The compressor allows me to get the trailer and leaking tire to the tire shop with no risk and minimum inconvenience.

And I do have a full size spare for the tow vehicle as I need it to get the flat tire to the repair. Again; in my experience, I haven't had a total tire failure in a couple of decades so I reevaluated the need to carry a trailer spare at all.

[Raz]

I just fixed a puncture on my CRV on Wednesday. I guess it all depends on where you drive. In my case I'm atleast 5 miles from pavement.

[Justus C]

Thanks for the feedback, many good points made. Foremost: Does it even matter or will it hit the trailer body first? And I don't know, but it's something to check for next time I have it home.

Handling with a simple drop hitch is less than ideal, but adequate. Most of the problem seems to be in the rear suspension; the ride gets awfully bouncy with the trailer attached. (Separately I am looking at sumosprings to help this issue.) I worry that any method of extending the hitch will degrade handling since it increases the lever arm that the trailer is acting on.

There are options for the spare tire, but I'm more curious about cutting into my turning clearance. Whether it's another propane tank, a spare tire, or a little storage box, something is going on that tongue. This trailer has no shortage of storage space (though limited to 700 lbs); it's issue is that so much storage is concentrated behind the axle. I just don't think it's possible to have the trailer loaded up for travel and still be balanced. I want permanent weight added far forward to counteract that.

[Raspy]

Justus,
I noticed that the axle was positioned pretty far forward on the Hymer. It does look like something you'll have to consider.

[Dick Kasnick]

The easy way to figure this out is to hook up the trailer. Jackknife it to the max. Have somebody watch for you!!! Then take a tire and position is in various positions to see what fits. Easy Peasy...

Originally Posted by Justus C

Is there a consensus on how tight an angle you should be able to make with your trailer hitched up? I'm referring to bumper pulls in this case, not 5th wheels.

For the past three evenings I have been trying to think of a way to mount a spare tire to my Hymer Touring GT. For the life of me I can't come up with any solution other than mounting it vertically in front of the battery and propane tank. This thing doesn't have clearance to mount it under the tongue; doesn't have the tongue length to side mount it; has no underbody frame to speak off for a BAL hide-a-spare; and has an integrated bumper unsuitable for mounting. I really don't want to carry it in the rear storage compartment or in our TV.

The diagram attached (not to scale!) shows a typical A-frame tongue, my pole tongue setup, and a modification I'm tossing around. It ignores the length of your hitch shank. Suffice to say every 1" that the hitch(not counting the ball) protrudes past the bumper adds about 2.5°. I'm aware of the downsides of a longer shank.

It looks like a typical A-frame tongue forms a 50° angle, allowing the TV and trailer to be oriented up to 65° apart. The limitation is the angle of the tongue. Attached is a photo of an owner modded jack-mounted spare, which would significantly reduce this angle. Is 65° an accepted industry minimum or just a standard?

My trailer has a pole tongue with a battery and propane tank. The propane tank is the larger object, projecting about 13" from the tongue. The tank limits the angle. (I know it's round; I treated it as a square for simplicity.) I calculated the max difference in orientation as 64°.

I want to add a vertical spare tire mount right in front of the battery. The spare will be 26" in diameter; on a 3" tongue, 11.5" will hang off either side. I think it will take up about 7" of tongue length. This will reduce the max orientation difference to 60°.

Outside of backing up, will I ever notice the loss of mobility? Is it dangerous or otherwise not recommended to do stuff like this?

[thrifty bill]

Broke a rear light on my F150 backing up our Casita. The Casita has a very short A frame up front. Longer makes backing up easier.

[Luc Riezebos]

Just for info, some province's in Canada require trailers to have a spare available. I have known a few people that have gotten ticketed for not having one.

[Justus C]

Originally Posted by Luc Riezebos

Just for info, some province's in Canada require trailers to have a spare available. I have known a few people that have gotten ticketed for not having one.

Ontario must not be one! I purchased the trailer from Sicard RV in Smithville, ON and they did not provide spares with these.

[wvorih]

My Eriba Pan, 1989, came with the spare mounted on a simple swing down rack under the trailer, accessable from the rear. It works well even if a bit messy to access. I would make and send a picture if pressed for it.

Ref the comment about the axel being farther forward than American trailers. It is typical in Europe for the axel to be near the balance point so that the tongue weight is low. My Pan has a tongue weight of 80 pounds. And BTW, it handles extremely well. The instruction book urges you to keep the loaded material near the axel, away from the tongue and rear, to reduce the polar moment of inertia. You will see these Eribas going 80mph plus on the Autobahn in Germany without stability issues (even if the drivers might have mental issues IMHO).

[Lisa in Michigan]

We just carry the spare trailer tire in a plastic zippered bag in the car.

[Teddy]

Probably as important as trailer tongue clearance angles is the amount of trailer weight, where that weight exists along the length of the trailer and the number of axles under the trailer. My own observation have been that single axle trailers can withstand lateral forces better than dual axle trailers. And, loading directly over the axles minimize wear and tear and lateral suspension forces when turning.

Trailer wheels don't like lateral forces, especially dual axle trailers with less durable fancy alloy rims. Consequently, if you are towing or maneuvering a dual axle trailer, you must compensate and minimize the severity of the trailer to TV angle especially when backing. Just listen to the creaking and groaning of suspension components or tires skidding laterally on pavement when making extreme trailer turns. That noise is a signal that lateral forces exist on the entire suspension, especially wheels and hubs.

Also, I prefer sturdy steel trailer wheels, preferably galvanized to modern alloy rims and I compensate when maneuvering a dual axle trailer by minimizing turning radiuses, especially when repeatedly backing and stopping from a dead stop.

Become very familiar with the turning characteristics of your trailer/tow rig combination and use good planning when backing to minimize severe angle maneuvers. I managed a recreational trailer and motorhome facility for several years and observed many cracked, bent and broken alloy rims and bent axle spindles, especially on dual axle travel trailer (pull trailers). More often, damage goes undiagnosed until a disaster occurs during travel with very inconvenient consequences and possibly costly residual damage.
-Teddy

[wvorih]

Originally Posted by Teddy

Probably as important as trailer tongue clearance angles is the amount of trailer weight, where that weight exists along the length of the trailer and the number of axles under the trailer. My own observation have been that single axle trailers can withstand lateral forces better than dual axle trailers. And, loading directly over the axles minimize wear and tear and lateral suspension forces when turning.

Trailer wheels don't like lateral forces, especially dual axle trailers with less durable fancy alloy rims. Consequently, if you are towing or maneuvering a dual axle trailer, you must compensate and minimize the severity of the trailer to TV angle especially when backing. Just listen to the creaking and groaning of suspension components or tires skidding laterally on pavement when making extreme trailer turns. That noise is a signal that lateral forces exist on the entire suspension, especially wheels and hubs.

Also, I prefer sturdy steel trailer wheels, preferably galvanized to modern alloy rims and I compensate when maneuvering a dual axle trailer by minimizing turning radiuses, especially when repeatedly backing and stopping from a dead stop.

Become very familiar with the turning characteristics of your trailer/tow rig combination and use good planning when backing to minimize severe angle maneuvers. I managed a recreational trailer and motorhome facility for several years and observed many cracked, bent and broken alloy rims and bent axle spindles, especially on dual axle travel trailer (pull trailers). More often, damage goes undiagnosed until a disaster occurs during travel with very inconvenient consequences and possibly costly residual damage.
-Teddy

Comment about trailer to car angle:
Go to a parking lot and turn the steering wheel to the lock and make a turn. Be careful that nothing touches back there. I think it's important that you can do this so as not to lose total turning radius of planning to do something on the tongue that might reduce this angle.

My rig does this easily so I can make a U turn in most any street.

While making this Max turn, note where the end of the trailer is in you're side mirrors. Different on each side! Then when backing up, this mental mark is your "Jack knife" limit. Very important limit!!!

[Raspy]

Originally Posted by Teddy

Trailer wheels don't like lateral forces, especially dual axle trailers with less durable fancy alloy rims. Consequently, if you are towing or maneuvering a dual axle trailer, you must compensate and minimize the severity of the trailer to TV angle especially when backing. Just listen to the creaking and groaning of suspension components or tires skidding laterally on pavement when making extreme trailer turns. That noise is a signal that lateral forces exist on the entire suspension, especially wheels and hubs.

Also, I prefer sturdy steel trailer wheels, preferably galvanized to modern alloy rims and I compensate when maneuvering a dual axle trailer by minimizing turning radiuses, especially when repeatedly backing and stopping from a dead stop.

It's not as simple as saying galvanized is stronger than aluminum. All DOT approved wheels have a rating on the back that you can read to understand the load it is rated for. Any trailer wheel is designed for trailer use. This means they are designed to handle side loads.

Standard 16" galvanized, six bolt, steel trailer wheels from Etrailer are rated for a 3,050 lb load. The aluminum wheels on my tandem axle Oliver are rated for a 3,200 lb load. The aluminum wheels are stronger in this example. So the generalization that aluminum wheels are weaker, is not true.

The possible noise you hear from a standard tandem axle suspension is normal. There are a number of pivot points that have some built in play to prevent binding. They also can wear and become loose as the nylon bushings wear. Excessive looseness can be fixed by going to a Dexter Heavy Duty kit which replaces the pins, shackles and equalizer. It has bronze greaseable bushings and will last a lot longer than the plastic standard bushings. If you are concerned about the tandem suspension system, look carefully at the cheap standard bushings that wear clear through in a few thousand miles, and how the shackle pins wear over time. The whole system can become dangerously weak over time. Not from a few sharp turns, but from miles of highway flexing and debris in the pivot points.

It might be nice if we could always drive in a straight line, but we can't. You are not going to hurt anything by turning sharp. And the next time you want to be concerned about side loads on wheels, consider the front wheels on heavy pickup trucks as they make turns. On my truck for instance, each front wheel is carrying over 2500 lbs and steering the truck around sharp turns on the road as it goes over bumps. That is a severe side load. But it is designed for it and never a problem. Even aluminum wheels with low capacities are fine with tandem axle turns, they are much more subject to damage from scuffing against curbs, for instance.

[Civilguy]

Originally Posted by Justus C

Is there a consensus on how tight an angle you should be able to make with your trailer hitched up?

Uh, no - ? (Just a guess here!)

Originally Posted by Justus C

Outside of backing up, will I ever notice the loss of mobility? Is it dangerous or otherwise not recommended to do stuff like this?

I expect it won't matter pulling forward. However, there are many variables, such as the shape of your tow vehicle's body panels, the taillight locations, etc.

The good news is that you can test and refine this idea cheaply and easily.

Mock up the proposed spare tire with cardboard and take it someplace like an empty parking lot. Then you can check it out in detail, maybe with an observer, maybe with a back-up camera (our camera can be enabled when not in reverse). Maybe even use talc or something similar on the cardboard which would leave a mark on the vehicle.

The impact on the tongue weight will be substantial. As to how the A-frame would hold up structurally, the proposed location is not coincident with the location of the maximum bending moment, so I suspect you might be okay there.

If none of this works out, mount a swing arm with a stub axle on the rear part of the trailer's frame, mount the spare tire on the axle so it rolls on the ground to bear the weight, and Bob's your uncle!

Or, better yet, change the trailer to dualies and you'll have two "spares"!