Trailer Ride Attitude....

[Doug Mager]

I'm in the midst of trying to set a correct ride attitude on our new truck ( with different height ball mounts) for our Trillium.

I have forgotten, is it better to have the trailer a little nose down on the ball, level to ground or a little nose high?

[Chester Taje]

I run my trailers level to the ground.

[Frederick L. Simson]

I always heard that Level is the most desirable, but if you cannot get it perfectly level, slightly nose down is the next best thing. Nose up is a big contributer to sway problems.

Having double axles on my Fiber Stream makes towing level more critical than it would be with a single axle, to get even displacement on all 4 tires...

[Brian B-P]

I agree with Chester (my B1700 is as level as I can get it) and Frederick (err on the low side).

I'm not sure why it matters so much, but I have three theories:

• raising the tongue shifts the centre of mass back, changing the load distribution to less nose-heavy, which is generally assumed to reduce stability
• if the tongue is higher, the lateral force at the hitch is higher on the tow vehicle (and likely above the rear suspension roll centre), potentially making it less effective in controlling the trailer's lateral position
• aerodynamic forces due to air flow over the front of the body are changed

It could be that none of those are significant, or all of them, or something entirely different...

[Doug Mager]

This issue isn't such a big deal with the truck as it seems to handle the grosely overloaded trailer nicely either nose high or level. I'll maybe need to take another look at how it sits behind our ol Plymouth..

[John & Sandy M]

Approximately level would be best. The thing to remember is that the tongue weight increases with a "nose down" attitude on the trailer. For a 13' this probably isn't a big deal but with the 16-17' trailers you can easily exceed the vehicle tongue weight for a tug with a 3500 tow capacity. Our Scamp tows with a slight "nose up" attitude with a 350 lb. tongue weight (we tow with a Dodge Durango with a 5000 lb. capacity). No problem with sway.

[Con]

I think you are all missing an important point here.

Trailer axles, like the suspension on all cars have a built in geometry so that they track properly while traveling down a road.
If you look at a bunch of torsion bar axles sitting on a rack in some place like Prince Auto they all look bent. I recall walking by a clerk and a customer in Princess Auto one day and overhearing the customer accusing the clerk that all their axles where damaged. The clerk was a loss for words so I couldn't help but stop and explain to both of them about camber and toe-in on axles.

The principals of alignment date back some 2000 years when wagons, carts and chariots began using wheels. These principals are still in the suspension of our vehicles to this day.
I did a great deal of research into alignment principals when a friend who builds show cars and street rods asked me to design and produce a set of fabrication drawings for an independent front suspension system for street rods. There are things like caster, camber, toe-in, scrub radius, anti-dive and the Ackerman principal involved.

When I started restoring a 100 year old horse carriage years ago I had to do extensive research in to the design of wheels and alignment. Some of the info I found was in book that where almost 100 years old. The terminology was a little different (Swing) was toe-in and (Gather) was camber. Caster was not a problem because they didn't use king pins.

As far as trailers, there is only toe-in and camber involved so if you lift or drop the tounge that changes the the alignment and as a result you can have problems that the trailer will not track down the highway properly (wander) or roll easily, will cause severe scuffing on the tires to name a few. A case in point, We only had 8,000 miles on our brand new all alum horse trailer and I noticed the outside of all 4 tires were scuffed badly. I took it into a shop and they found the torsion bar axles had 3/8" toe-in instead of 1/8".

So the gist of this is: Keep the trailer a level and parallel possible to the ground and you will have far less problems towing.

PS The independent suspension system turned out beautify and he has used it on a number of customers street rods since doing his own.

Hope this helps

[Joe Z]

for me level is the best but i seen a few posts that said if you can't get level then go lower because you can stop at night and just crank your gear down to raise the front of the trailer to level and good-night...... Can't do that when it's higher you have to unhook to get level.
Joe

[brendadave]

I'm in the midst of trying to set a correct ride attitude on our new truck ( with different height ball mounts) for our Trillium.

I have forgotten, is it better to have the trailer a little nose down on the ball, level to ground or a little nose high?

Hi Doug, did you measure how far off the ground your hitch coupler needs to be to be level? I got a differnt tow vehicle and didn't bother to measure the old one before I sold it, so now I'm trying to figure out how high my hitch (draw bar) needs to be.

I'm not having much luck measuring in the driveway with all the slope.

Thanks.