Why are some 5th wheel trailers significantly off level when towed?

[oldryder]

Rookie considering a 5th wheel. I note that pickup/5th wheel rigs going down the road can be perfectly level or off level with the front of the trailer raised considerably.

Just wondering what causes the difference assuming towing with the trailer level is preferred.

thx to anyone taking the time to educate a noob.

 

[NY_Dutch]

While towing level is the ideal, there isn't always enough adjustment available in the pin box or hitch to achieve that.

 

[steveblonde]

Setting up a 5er is no different from a bumper pull really. You need to match the truck with trailer and adjust the pin box up or down and the hitch up or down. Todays trucks sit a bit higher than before but most can be configured to be close. Of course there are always exceptions and you may need to buy a different pin box or hitch with more adjustments for your situation, and of course like anything if the operator sets it up wrong you will have issues just like a bumper pull

 

[Great Horned Owl]

A 5th wheel will be off level if the hitch is too high, or if the pin pox is too low. That being said, many times being off level is an illusion. On 5th wheels, the floor is not flat. there will be a step or two up into the front section. In order to have a decent amount of head room, the roof is also raised in the front end. When you see the roof not level your mind is tricked into believing the the entire trailer is not level.

Joel

 

[Rene T]

Typically it’s because the truck it too high and adjusting the hitch to lower the front of the trailer will not work at times because you must maintain 6” clearance between the sides of the truck and the bottom side of the trailer. You can go as little as 5” but the preferred is 6”. The one thing that can be done in this situation is flip the axles. What I mean by that is typically the trailer comes with the axles on the top side of the leaf springs to keep the trailer as low as possible. To get the trailer up a little in the back, you flip the axles so they will be on top of the springs. You can gain almost 5” by doing that. But keep in mind, it makes it a little harder stepping up on the 1st RV step.

 

[donn]

Because so many people do not comprehend the idea of correct towing. Towing off level places undue stress on the tires or the pin box depending on which way its off level. Ideal is level or just slitely down on the pin. Towing otherwise unloads the pin weight which can cause unstable towing.

 

[uchu]

Because so many people do not comprehend the idea of correct towing. Towing off level places undue stress on the tires or the pin box depending on which way its off level. Ideal is level or just slitely down on the pin. Towing otherwise unloads the pin weight which can cause unstable towing.

Well, we all know that when it comes to towing, some people leave logic and common sense out the window...

 

[Lou Schneider]

And it's a home made dually - you can almost see the rear axle bending under the weight!

 

[Alan_Hepburn]

The one thing that can be done in this situation is flip the axles. What I mean by that is typically the trailer comes with the axles on the top side of the leaf springs to keep the trailer as low as possible. To get the trailer up a little in the back, you flip the axles so they will be on top of the springs. You can gain almost 5” by doing that. But keep in mind, it makes it a little harder stepping up on the 1st RV step.

Actually you don't "flip" the axles at all: you unbolt everything and move the axles from the top of the springs to the bottom of the springs. Trailer axles are built so that they "bow" upward in the center when they're at rest. This is so that when they are loaded they flex down so that they are straight. If you flip them over so they bow downward then your trailer will have excessive camber in the wheels.

 

[Rene T]

Flip the axles us a term used here to do what I said. Yes the axles are bowed and would have to have the bow facing up when done. We know that. And there would be a little welding involved because the pads that springs sit in or under would have to be cut off and welded back on the opposite side of the axles.

 

[steveblonde]

fipping the axles also raises the center of gravity and can create instability - same a s putting a lift kit on a truck - however, in this case a raised truck and raised trailer would create a real monster, not that people dont do it its just not advisable

 

[Carbonation]

Level is preferred.
RV delivery drivers usually have their hitches as high as possible and just live with it because adjusting the hitch for each rig is time consuming.
On the other end of the scale is the guy that thinks he can tow a huge 5'er with a SRW truck and it's sagging because he is over weight.
When I installed my B&W they had a detailed procedure for setting up height. I'm right at 6 inches between truck and trailer, and my trucks squats just about 2.5 inches when loaded, making everything nice and level.

 

[longhaul]

Flipping the axles is a old term we used when all trailer axles were straight. AS mentioned all we did was rotate the axle so the spring perches were on top.
The term is still used even with axles that come camber bowed.

 

[Edd505]

Because so many people do not comprehend the idea of correct towing. Towing off level places undue stress on the tires or the pin box depending on which way its off level. Ideal is level or just slitely down on the pin. Towing otherwise unloads the pin weight which can cause unstable towing.

yep they hookup and go. Anyone serious about RVing and traveling long distance educates themself about safe towing. How many had no idea ST tires were speed rated at 65? (yes some newer are more) How many know nothing about weights? The list goes on.

 

[Rob&Deryl]

yep they hookup and go. Anyone serious about RVing and traveling long distance educates themself about safe towing. How many had no idea ST tires were speed rated at 65? (yes some newer are more) How many know nothing about weights? The list goes on.

Not all ST tires are 65. The real message is to know the whys and wherefores of trailer tire specs. Size, load rating, & speed rating. Gotta know them all.

 

[Edd505]

Not all ST tires are 65. The real message is to know the whys and wherefores of trailer tire specs. Size, load rating, & speed rating. Gotta know them all.

If you read what I said I specifically said 65? (yes some newer are more)

My post: Anyone serious about RVing and traveling long distance educates themself about safe towing. How many had no idea ST tires were speed rated at 65? (yes some newer are more) How many know nothing about weights? The list goes on.

I ran LT's years because of the ST poor performance and 65 speed rating. I have just recently put Sailun ST S637 tires on because of the good reviews and 4000LB rating each.

 

[MtnGoat]

Just wondering what causes the difference assuming towing with the trailer level is preferred.

Keeping the RV level means the axles/tires are loaded equally. You can use public scales to be exact. Equal loading means reduced wear on the tires and bearings.

We had to flip the axles and use 2" riser blocks to accommodate our 2015 2500 Silverado Z71. Also had to drop the truck rear 2" as the pin box was at the limit. The older trailers (lower) and newer trucks (higher) can require significant modification for a properly rigged package.