Leveling a tandem axle trailer

[ssobol]

I wonder how much of a difference 3/4 of an inch of tilt really makes. Back at the wheels the difference will be a lot less. The other question is where is the loaded CG of the trailer? The difference in the weight on each axle (even if the trailer was perfectly level) could account for the temp difference.

If you have brakes on all wheels the ones in the front will be doing more of the work and will probably have higher temps.

 

[Sunbeam]

I wonder how much of a difference 3/4 of an inch of tilt really makes. Back at the wheels the difference will be a lot less. The other question is where is the loaded CG of the trailer? The difference in the weight on each axle (even if the trailer was perfectly level) could account for the temp difference.

That's a good point. I suppose both contribute. I have my trailer basically "perfectly" level and I also weighed recently. I got 1900# front/1800# rear for the trailer axles, but that was me carrying a bunch of stuff in the boat (tools etc.) that were not strictly boat related. I'll have to re-weigh sometime without those things in the boat (although they were reasonably well distributed fore and aft). My temps do run pretty consistent between all four hubs, although of course there is a bit of variation. I haven't noticed any distinct difference between the two axles though.

 

[journey on]

I've been following this thread and I'm somewhat surprised as to what lengths people are going. The true test is: everything stable while hauling and do the tires show any abnormal wear?

First of all, lets define a "level" trailer. The one under Journey On is an E-Z Loader, consisting of 2 main side spars and a tongue. When I look at it there's a curve from the hitch to where the tongue attaches. I couldn't get a level to less than a couple of inches. How are you measuring 3/4"?

Also, I ran the trailer nose down for a couple of years, since I was too lazy to mess with the hitch and level it. No tire problems. I finally leveled it (by eye, not inches,) and started to have tire problems. I blame the tires not the leveling.

All trucks ( and any other vehicle with springs) will sag when loaded. That's how springs develop the force to support the load. On the Dorf that hauls Journey On, it's say 4", and I don't worry about it; I think that's normal. If you don't like the sag, get sway bars but remember to keep a load on the rear wheels for traction. Again, it's normal and if it doesn't affect stability, nothing to worry about.

As long as the trailer tires aren't loaded beyond their rating, the difference in weight between axles isn't important, though one should keep them somewhat equal. That's because when turning, you want both wheels to scrub equally, or at least I do.

And I think that if you take care of the hubs, brakes before you leave, you'll not have any problems. I haven't and I've been hauling trailers for 50 years. I don't know their temperature, but i haven't fried anything.

Tires are a different matter. In the last few years, I had to use Chinese tires and my luck hasn't been good. But the trailer is level.

I guess my message is to relax, do your best and enjoy the trailerable aspect of a C-Dory. If you're hauling a 22' C-Dory with a 1/2 ton truck, that's a perfect match.

Boris

 

[hardee]

Boris,

I'm with you. If there is no problem, then be happy and trailer. My "3/4 of an inch" is close enough for me, and the 10 degree temp is not enough to worry about. I know these points as a standard for me and monitor to stay within reason.

With my single axle Pacific I always towed with the bow just a little high. With this one it is just slightly reversed. It's all good as long as the temps and tire wear stay within range.

Harvey
SleepyC:moon

 

[ssobol]

When I bought my CD22 I measured the unloaded ball height on the truck of the guy who sold it to me. On my vehicle I bought the receiver that got my ball closest to that height. I hook the trailer up and tow it where ever and haven't thought about the trailer being level or not since.

The trailer angle is going to vary based on the load in the vehicle, the load in the boat, the age of the shocks and springs, other stuff, and is not going to be constant. Unless it is noticeably off ("hey, that looks odd...") it probably doesn't make that much difference and I don't worry about it.

The rating is the rating, not the limit. There is some margin between the rating and the failure limit. Granted a tire with less load on it will probably last longer, but a tire rated for 1360# is not going to suddenly fail if you put 1361# on it.

I think most people's trailer tires age out before they wear out. The tires on my trailer are about out of time based on age, but the tread looks pretty new.

The only trailer tire failure I have had is from when I cut to close to a sharp curb and caused a leak in the sidewall. The tire would loose about half pressure in 24 hours.

 

[thataway]

I've been following this thread and I'm somewhat surprised as to what lengths people are going. The true test is: everything stable while hauling and do the tires show any abnormal wear?

The thread started with "what is best?". It is best to have the loads on both axles close as possible to being equal. (the assumption is that axles are properly placed). As below, you won't know if there is tire wear, until it is visible. Best to try and prevent the wear.

For me the measurement is at the rear and front of the Aluminum "I" beam on the trailer frame. So after Bori's question about how to measure:

When I look at it there's a curve from the hitch to where the tongue attaches. I couldn't get a level to less than a couple of inches. How are you measuring 3/4"?

I used both visual sighting, and a laser beam to check, and if there is any sag in the Aluminum beam on the 22 Trailer, it is less than 1/8". You measure the "level" as the tow vehicle is loaded, and on a flat, level surface. This is the advantage of an adjustable ball hitch.

I have had the misfortune to fry a bearing on a hub, probably due to dragging calipers on a long down grade with surge brakes (C Dory 25). There are enough stories and trailers along the side of the road, to make it a prudent, and routine to check the hub temps--even if the bearings are repacked before any significant haul (as mine are). It takes couple of minutes (good exercise) to walk around a trailer, and take IR temps on the hubs, calipers and tires. We do this regularly every two hours--the only time I had a problem was when we violated this rule because of traffic and lack of a place to stop and check.

With a single axle trailer, the "level" is not as critical.

Sunbeam, it would have been interesting to see what the hitch weight was--since your two axles weight was 3700 lbs--was the hitch weight over 500 lbs?

I think most people's trailer tires age out before they wear out. The tires on my trailer are about out of time based on age, but the tread looks pretty new.

This is most likely true--but of course it depends on how much you tow the trailer each year. C Dory owners may be more frequent travelers, due to the nature of our boats and life styles. We tend to put from 4,000 to 8,000 miles a year on the boat trailer, but the average boater is probably a few miles back and forth to a ramp. On the C Dory 25 the first set of tires was shot in about 7500 miles. Earlier I had posted that there seemed to be little difference in wear between the tires--until I put the micrometer on the tread depth! I suspect that these bias Chinese tires will not last over 10,000 miles (even being leveled)--or a couple of years--the next ones will be radials. On our RV, we put over 60,000 miles when the tires timed out--at 6 years, and there was plenty of tread left. I know that some tire dealers sell these tires to on the road truckers for their trailers (although my dealer claimed he didn't).

 

[ssobol]

Even with the trailer level there is more weight on the front tires than the rear ones. This is because the loaded trailer CG is somewhat forward of the centerpoint of the two axles in order to get the tongue loading right.

When towing if I can put my hand comfortably on the hub I'm pretty sure that things are ok. I don't need some fancy (or cheap) gadget to tell me that.

We tend to put from 4,000 to 8,000 miles a year on the boat trailer

I don't put that many miles on my car, let alone my trailer.

 

[rogerbum]

Even with the trailer level there is more weight on the front tires than the rear ones. This is because the loaded trailer CG is somewhat forward of the centerpoint of the two axles in order to get the tongue loading right.

When towing if I can put my hand comfortably on the hub I'm pretty sure that things are ok. I don't need some fancy (or cheap) gadget to tell me that.

We tend to put from 4,000 to 8,000 miles a year on the boat trailer

I don't put that many miles on my car, let alone my trailer.

The fancy gadgets are pretty cheap and you get to keep your hands clean! Also, as one ages, I imagine it's a bit easier to point and get the temp than to bend over - especially for a tall guy (like Bob). That said, I haven't yet gotten around to getting an IR thermometer for the hubs (I have one for chocolate making but that's another story). So like you, I check with my hands. If I remember, I'll pick up an IR thermometer sometime this winter.

 

[Will-C]

If the recommendation is to have the trailers frame level then that's the target. We have twenty thousand plus miles on a set of Carlisle 14" radials and they still look good. We trailered to Flaming Gorge, Grand Teton, Yellowstone and up to Lake Superior from Pa. in one late summer trip. Not to mention from Canada down to Florida on a number of occasions. Our Float trailer with torsion bar axles is as steady as a rock at any speed . Having the boat positioned on the trailer correctly is also key as tongue weight is as important as the leveling. The more attention paid to all of the details the better your trailering experience is likely to be including how well your brakes function. The more confidence you have in trailering will let you enjoy more places; no matter what the distance might be. For us IMHO that is the true beauty of the C-Dory line of boats is the relative ease of trailering to more distant destinations.
D.D.

 

[potter water]

Air bags are the ideal solution. We shift from the Dory to a slide in truck camper, both of which need to be level, and sometimes we are towing both. In that case, I pump the air rides to make sure he boat is level. My dodge dealer had a sale on air bags 250 bucks installed. Check around. Mine are firestone and have been holding up well. Nice to be able to pop the trailer level with a little air. I did not opt for the complexity and high cost of integrated air pump. Rather, I use my 12 volt harbor freight 12 buck pump, and my wife watches the inclinometer on the trailer for level.

I also set the bags to slightly unload the over load spring on my dodge. So far, my trailer and truck geometry work out just about right. Overload springs half unloaded and a level boat trailer.

 

[Sunbeam]

I've been following this thread and I'm somewhat surprised as to what lengths people are going.

I try to stack the deck in my favor. The time/effort I spent getting things level was a drop in the bucket of overall boat maintenance/care time.

Sunbeam, it would have been interesting to see what the hitch weight was--since your two axles weight was 3700 lbs--was the hitch weight over 500 lbs?

It's between 350# and 380#. So around 8%-9% or so. Tows beautifully like that, so I'm happy with it. I have towed with a bit less tongue weight (around 7%) and still towed well, so there is some leeway.

 

[thataway]

Air bags are the ideal solution.

I would agree with that--and if I could find a set for $250 installed, I would be buying them tomorrow! However, the air bags, do compensate for a potential overload on the rear axle. I have considered them (and do have them on the RV)--but so far, the various trucks I have owned have done well without them. Many trucks call for an equalizing hitch when you in the upper capacity of towing weights. Not sure why people seem to neglect that option--since an equalizing hitch has many advantages, and was part of the solution of excessive tire wear on the C Dory 25 that I owned.

 

[journey on]

Bob,

I tried an equilizing hitch for towing Journey On. It didn't work out, as follows.

Journey On is towed by a F-250, Super Duty whatever that means. A standard 3/4 ton pickup. As I mentioned above, it sagged 4"-6" whenever I loaded the trailer on AND threw in the stuff in the bed. I installed an equilizing hitch, figuring everything should be level. And then went to Washington.

Going up a hill in Marysville, to visit a friend, on a rainy day, I had to take another pass at the hill, because I didn't have enough traction. One of the many thrill of my life, backing down a hill on a rainy day against traffic. Remember, those equalizing bars are springs which transfer weight from the rear axle to the front. That means less weight on the rear and less weight means less traction. And, of course you need traction to pull the boat up the launch ramp as well as to go up hills.

Took those equalizing bars of and accepted the rear sag because I need traction when towing that boat. Actually, I didn't notice any difference between the ride or handling, either way. One less thing to worry about. Back to the KISS method.

Boris

 

[thataway]

Going up a hill in Marysville, to visit a friend, on a rainy day, I had to take another pass at the hill, because I didn't have enough traction. One of the many thrill of my life, backing down a hill on a rainy day against traffic. Remember, those equalizing bars are springs which transfer weight from the rear axle to the front. That means less weight on the rear and less weight means less traction. And, of course you need traction to pull the boat up the launch ramp as well as to go up hills.

Quick solution to the traction problem is to unload (unhook the chains takes a lot less time than backing down the hill) on the truck --lack of weight in the pickup bed is one of the reasons I prefer a SUV type of truck). Hook the chains back up when you don't need super traction… Of course there is the option of a 4 x 4 (the current vehicle is only one of 3 4 x 4 we have owned in over 60 years of towing boats)..

Always different opinions, and options! Regards.

 

[rogerbum]

Air bags are the ideal solution. We shift from the Dory to a slide in truck camper, both of which need to be level, and sometimes we are towing both. In that case, I pump the air rides to make sure he boat is level. My dodge dealer had a sale on air bags 250 bucks installed. Check around. Mine are firestone and have been holding up well. Nice to be able to pop the trailer level with a little air. I did not opt for the complexity and high cost of integrated air pump. Rather, I use my 12 volt harbor freight 12 buck pump, and my wife watches the inclinometer on the trailer for level.

I also set the bags to slightly unload the over load spring on my dodge. So far, my trailer and truck geometry work out just about right. Overload springs half unloaded and a level boat trailer.

Agreed. I put airbags on both my current and previous tow vehicle. $250 installed is a great price. I think I paid $750 installed on the first vehicle. The second time around, I did it myself but the kit for my Tundra was around $250 on-line. It only took a couple of hours and would only take an hour or so if you have experience installing the things.

 

[redbaronace]

Air bags are the ideal solution. We shift from the Dory to a slide in truck camper, both of which need to be level, and sometimes we are towing both. In that case, I pump the air rides to make sure he boat is level. My dodge dealer had a sale on air bags 250 bucks installed. Check around. Mine are firestone and have been holding up well. Nice to be able to pop the trailer level with a little air. I did not opt for the complexity and high cost of integrated air pump. Rather, I use my 12 volt harbor freight 12 buck pump, and my wife watches the inclinometer on the trailer for level.

I also set the bags to slightly unload the over load spring on my dodge. So far, my trailer and truck geometry work out just about right. Overload springs half unloaded and a level boat trailer.

Agreed. I put airbags on both my current and previous tow vehicle. $250 installed is a great price. I think I paid $750 installed on the first vehicle. The second time around, I did it myself but the kit for my Tundra was around $250 on-line. It only took a couple of hours and would only take an hour or so if you have experience installing the things.

Do you have the model number of the Tundra airbag kit that you ordered online?

I might pick up one myself and see how difficult it is to install with a friend.

 

[rogerbum]

Air bags are the ideal solution. We shift from the Dory to a slide in truck camper, both of which need to be level, and sometimes we are towing both. In that case, I pump the air rides to make sure he boat is level. My dodge dealer had a sale on air bags 250 bucks installed. Check around. Mine are firestone and have been holding up well. Nice to be able to pop the trailer level with a little air. I did not opt for the complexity and high cost of integrated air pump. Rather, I use my 12 volt harbor freight 12 buck pump, and my wife watches the inclinometer on the trailer for level.

I also set the bags to slightly unload the over load spring on my dodge. So far, my trailer and truck geometry work out just about right. Overload springs half unloaded and a level boat trailer.

Agreed. I put airbags on both my current and previous tow vehicle. $250 installed is a great price. I think I paid $750 installed on the first vehicle. The second time around, I did it myself but the kit for my Tundra was around $250 on-line. It only took a couple of hours and would only take an hour or so if you have experience installing the things.

Do you have the model number of the Tundra airbag kit that you ordered online?

I might pick up one myself and see how difficult it is to install with a friend.

I don't recall the exact number but they were Firestone Ride Rite airsprings. All I did was go online with my truck model and year and visit a few web sites to get the best price. They are pretty easy to install. The hardest part is cutting off the rubber bumper at the base of the spring (I used a sawzall) and deciding where you want to put the fill valves. I mounted mine on the rear bumper inset one on either side of the license plate. If you can turn a wrench and read and follow directions, it's pretty easy.

 

[ssobol]

I used the kit from Airlift. It took an hour or two to install by myself.

Bit of a pain to shove the airbag into the spring. If it is cool/cold out it helps to soak the bladder in hot water to soften it up and make it more flexible.

It would be easier to get the bag in if you take out the springs first, but that is a whole other level of work.

 

[Will-C]

I'm thinking if the vehicle over squats from the tongue weight of a trailer some thought MIGHT be given to reducing the tongue weight by repositioning the boat on the trailer, loading the boat differently for road travel or choosing a vehicle that can handle the tongue weight with out getting crazy with air bags and the like. If a 1/2 ton pickup has 500 to 700 pounds of tongue weight plus the bed is loaded with gear that people with SUV's have to keep in the boat because they have no room in the tow vehicle. I think overloading the boat while on the trailer can be a cause of a trailer failure. At any rate I'm not seeing the pickup truck's rear axle being light. Balancing the load in between the tow vehicle and the trailer is important if it's at all possible. JMHO
D.D.

 

[rogerbum]

I'm thinking if the vehicle over squats from the tongue weight of a trailer some thought MIGHT be given to reducing the tongue weight by repositioning the boat on the trailer, loading the boat differently for road travel or choosing a vehicle that can handle the tongue weight with out getting crazy with air bags and the like. If a 1/2 ton pickup has 500 to 700 pounds of tongue weight plus the bed is loaded with gear that people with SUV's have to keep in the boat because they have no room in the tow vehicle. I think overloading the boat while on the trailer can be a cause of a trailer failure. At any rate I'm not seeing the pickup truck's rear axle being light. Balancing the load in between the tow vehicle and the trailer is important if it's at all possible. JMHO
D.D.

In my case, I did move the boat back on the trailer to reduce tongue weight to the extent possible but there are limits to what one can do in that regard. With a Tomcat, the tongue weight gets above 700 lbs and even my buddy's Silverado sees a bit of a drop when the trailer is loaded. Airbags allow one to provide extra lift to the rear of the truck when needed and to remove that lift when it's not.

When I had my 22, I had airbags installed on an Isuzu Trooper. While the Isuzu (rated to tow 5k) was not the ideal tow vehicle, it did the job (but only after I installed the air bags to stiffen the rear end). On the other hand, the Trooper was great SUV for other uses (camping, daily driver, family trips). With the airbags, I got "dual" use out of the vehicle that otherwise would not be possible. Since I tow less than 1-2k miles per year, it was more important to have the SUV utility that the ideal tow vehicle utility.

So, what to do is dependent on a lot of individual factors - finances, other needs, boat, trailer usage etc. Airbags are a tool that many find useful.