Trailer not level - air bags or taller hitch?

[security6]

Got a question about the best way to raise the tongue of my trailer when I'm towing it.
When towing my dual-axle trailer isn't level, the tongue of the trailer is lower than the rear of the trailer. It seems to me that having the trailer unlevel is putting more weight on the front axle of the trailer than the rear axle. I understand that for best towing performance, the trailer should be level. What is the preferred way to get a trailer level - add air bags to the truck or use a taller hitch ball mount?


Details on my setup:
Truck - 2001 Chevrolet Suburban K1500. The rear of the truck does squat/lower when the trailer is lowered on the ball mount
Boat - Larson 234 Escape on factory Larson dual-axle trailer.
Weight of boat/trailer - about 5000 lbs; I've never measured tongue weight
Current hitch - factory hitch with a 3/4" rise ball mount

 

[oldjeep]

Re: Trailer not level - air bags or taller hitch?

Depends, is the rear of your truck sitting low or level?

 

[security6]

Re: Trailer not level - air bags or taller hitch?

Depends, is the rear of your truck sitting low or level?

Without the trailer, the truck sits level. When the trailer is on the hitch, the rear of the truck is about 6" lower than when it is level. The front of the truck is also a tad lower, but the truck (with the trailer connected) is lower in the rear than the front.

 

[cribber]

Re: Trailer not level - air bags or taller hitch?

Spend the 5-10 bucks to have your boat, trailer and gear weighed at a truck stop or weigh station to take out the guess factor. Dropping a trailer on your hitch and having the rear end of the Suburban sag 6 inches might mean too much weight or you need to redistribute your load. All guesses without knowing what the total weight of your setup... Larson boats are known to be heavy because of the quality of their build.

Anyone have advice to offer?

 

[Expidia]

Re: Trailer not level - air bags or taller hitch?

Post a pic from the side showing the boat hooked to the trailer. It would be easier to diagnose your issue with a pic!

 

[security6]

Re: Trailer not level - air bags or taller hitch?

Spend the 5-10 bucks to have your boat, trailer and gear weighed at a truck stop or weigh station to take out the guess factor. Dropping a trailer on your hitch and having the rear end of the Suburban sag 6 inches might mean too much weight or you need to redistribute your load. All guesses without knowing what the total weight of your setup... Larson boats are known to be heavy because of the quality of their build.

Anyone have advice to offer?

I can do that, but I'm not sure what difference it will make. My suburban is rated to tow 8800 lbs, so even if the factory weight numbers are off by 20%, I'm still well within my tow rating. Would the answer change if my boat/trailer weighed 6000 lbs?

Now, it could be that I have too much tongue weight, but won't tongue weight change depending on whether the trailer is level or not? It seems to me that the forward axle will act as a pivot point, thus distributing more (or less) weight to the tongue and rear axle as the tongue is raised or lowered. So I don't really see the point of measuring tongue weight if the trailer isn't level. Am I missing something here?

Finally, do boats/trailers typically come from the factory with the weight distribution all out of whack? This is a factory trailer which was made and setup by Larson for my boat. I don't have much extra crap in the boat (a few skis, a wakeboard and some life jackets) that would throw off the weight distribution by much. I'm hesistant to start changing the factory setup, because the boat sits well on the trailer right now (about 1" of the rear bunk is showing).

I hope I'm not coming off as a jerk or being argumentative, because I'm not trying to be. Please do let me know if there is a hole in my logic somewhere.

 

[oldjeep]

Re: Trailer not level - air bags or taller hitch?

Without the trailer, the truck sits level. When the trailer is on the hitch, the rear of the truck is about 6" lower than when it is level. The front of the truck is also a tad lower, but the truck (with the trailer connected) is lower in the rear than the front.

Either you have wet noodles for springs or your tounge weight is way out of whack

 

[cribber]

Re: Trailer not level - air bags or taller hitch?

Exactly, and that's why you need to know your total weight, boat, gear, fuel, and trailer. Once you know how much you typically tow you can address the tongue weight. It should be roughly 9-15% with ideal being 10-12% of total weight from what I read. Measure the tongue weight with a portable scale while the tongue jack is set at ride height on the hitch. From here you have solid numbers to work from to make any necessary adjustments to balance out your load.

 

[rbh]

Re: Trailer not level - air bags or taller hitch?

All trucks squat when you add weight to them.
Might just be the fact that your hitch is not at the right level.

Park on flat area, chalk trailer wheels so it does not role away, jack the trailer off the ball and see how much the rear of the truck comes up and how far the trailer tongue goes up till it is level.

 

[dockwrecker]

Re: Trailer not level - air bags or taller hitch?

Your truck shouldn't be squatting more than a couple inches if your tongue weight is correct. My 03' Avalanche 1500 with 6200lbs behind it squats maybe 2" with a 550# tongue weight. No helper springs, no air bags. Doesn't squat at all with my weight distributing hitch. Trailer and truck are dead level. Just because your trailer was built for your boat doesn't mean anybody bothered to balance it. Moving your winch back 4-6" will make a huge difference in tongue weight. Get it weighed and adjust the tongue weight to 8-10% of the total weight of the trailer. After you get the balance right, the easiest way to level the trailer is with an adjustable drop draw bar. (hitch)

 

[JimS123]

Re: Trailer not level - air bags or taller hitch?

Check the drop (or rise) of your drawbar. See how much out of kilter the trailer is. Then Jack up (or down) the trailer tongue till the trailer is perfectly level. Note the difference and buy a new drawbar that is higher (or lower) as the case may be.

As a good starting point, the face of the drawbar (with no ball attached) should be about 17" off the ground (+- 2").

 

[Silvertip]

Re: Trailer not level - air bags or taller hitch?

You cannot put more weight on the front or rear axle on a tandem trailer whether it is sitting level or not. That can only happen if the trailer has torsion axles. A leaf sprung axle has an equalizer (also called a walking beam) between the front and rear axles. If you study the structure you will see the equalizer pivots and therefore the weight remains the same on both axles regardless of the trailer attitude. If the back end of the truck squats, obviously the trailer will not sit level. You have two choices 1) raise the truck or 2) add rise to the ball mount. I agree that if the truck is dropping six inches you have peanut butter springs or way too much tongue weight. The only way you know what that should be is to weigh the boat. 10 - 15% of total weight is suggested on the tongue..

 

[jeeperman]

Re: Trailer not level - air bags or taller hitch?

Does a standard K1500 Suburban have 6" of space between the axle and bump stops?

 

[Mi duckdown]

Re: Trailer not level - air bags or taller hitch?

I guessing your tongue weight is way to much. need to check that first.

 

[security6]

Re: Trailer not level - air bags or taller hitch?

Post a pic from the side showing the boat hooked to the trailer. It would be easier to diagnose your issue with a pic!

I'll have to do that. Solving this problem the right way might take a bit more investigating than I thought. I won't be able to get pictures and measurements until this weekend.

Park on flat area, chalk trailer wheels so it does not role away, jack the trailer off the ball and see how much the rear of the truck comes up and how far the trailer tongue goes up till it is level.

I'll do that this weekend. My driveway isn't level, so I'll have to find an empty parking lot somewhere nearby.

Your truck shouldn't be squatting more than a couple inches if your tongue weight is correct. My 03' Avalanche 1500 with 6200lbs behind it squats maybe 2" with a 550# tongue weight. No helper springs, no air bags. Doesn't squat at all with my weight distributing hitch. Trailer and truck are dead level. Just because your trailer was built for your boat doesn't mean anybody bothered to balance it. Moving your winch back 4-6" will make a huge difference in tongue weight. Get it weighed and adjust the tongue weight to 8-10% of the total weight of the trailer. After you get the balance right, the easiest way to level the trailer is with an adjustable drop draw bar. (hitch)

I might have exaggerated the 6" drop, but it is at least 4" or 5". Considering that a suburban and an avalanche are identical except for the body, my suburban shouldn't be dropping this much.

I figured since this was a factory trailer that it would have been balanced. It is looking like that needs to be verified.

As a good starting point, the face of the drawbar (with no ball attached) should be about 17" off the ground (+- 2").

I measured it tonight on the empty truck and it was 16.5".

You cannot put more weight on the front or rear axle on a tandem trailer whether it is sitting level or not. That can only happen if the trailer has torsion axles. A leaf sprung axle has an equalizer (also called a walking beam) between the front and rear axles. If you study the structure you will see the equalizer pivots and therefore the weight remains the same on both axles regardless of the trailer attitude. If the back end of the truck squats, obviously the trailer will not sit level. You have two choices 1) raise the truck or 2) add rise to the ball mount. I agree that if the truck is dropping six inches you have peanut butter springs or way too much tongue weight. The only way you know what that should be is to weigh the boat. 10 - 15% of total weight is suggested on the tongue..

As of matter of fact, this trailer does have torsion axles. It really is a nice trailer, which is part of the reason why I figured it was setup correctly at the factory.

Perhaps I do have peanut butter springs. We are the 2nd owners of this truck and I'm fairly certain it has factory springs. The truck does have a lot of miles (220k), but it is mainly a mall cruiser.

I guessing your tongue weight is way to much. need to check that first.

On my to-do list. I need to find a place that will let me use their scales.


Thanks all for the input. Measurements to come (hopefully) this weekend.

 

[Silvertip]

Re: Trailer not level - air bags or taller hitch?

Since the trailer does have torsion axles, then it behooves you to level the rig as these set-ups do not have equalizing capability and either axle can be easily overleaded. Except for moving the boat fore/aft or the axles fore/aft, there is no other balancing. You generally adjust the boat for the proper tongue weight. Since the selling dealer has no idea what else you will stuff into the boat after it leaves their lot you can easily add a couple hundred pounds of tongue weight with coolers, anchors, batteries, water, etc. It is always the owners responsibility to make sure the trailer is set-up properly before hitting the road. Never, ever, assume the dealer has set up the rig properly or that they even checked tire pressure and lug nut tightness.

 

[security6]

Re: Trailer not level - air bags or taller hitch?

Since the trailer does have torsion axles, then it behooves you to level the rig as these set-ups do not have equalizing capability and either axle can be easily overleaded. Except for moving the boat fore/aft or the axles fore/aft, there is no other balancing. You generally adjust the boat for the proper tongue weight. Since the selling dealer has no idea what else you will stuff into the boat after it leaves their lot you can easily add a couple hundred pounds of tongue weight with coolers, anchors, batteries, water, etc. It is always the owners responsibility to make sure the trailer is set-up properly before hitting the road. Never, ever, assume the dealer has set up the rig properly or that they even checked tire pressure and lug nut tightness.

While I don't know for sure, I suspect my trailer was chosen for my boat by Larson, not by a dealer. The trailer has a matching paint job to the boat, and even has Larson and the boat model painted on the trailer. I can't see a dealer doing that. I would hope Larson would set things up correctly, but we will see when I get it weighed.

 

[ultra_1968]

Re: Trailer not level - air bags or taller hitch?

Guys, I try and sit and read about 15-20 minutes a day on here to learn something. I don't know a lot about the marine world, but I'm trying to change that...

My Question after reading this thread, even after weighing the trailer, how do you determine what the actual tounge weight is versus what it should be?

As always, thank you for the help you give others (me).

 

[rbh]

Re: Trailer not level - air bags or taller hitch?

Guys, I try and sit and read about 15-20 minutes a day on here to learn something. I don't know a lot about the marine world, but I'm trying to change that...

My Question after reading this thread, even after weighing the trailer, how do you determine what the actual tounge weight is versus what it should be?

As always, thank you for the help you give others (me).

The easiest way to find out how much weight you have on your axles is to scale your vehicle and trailer.
start by weighing the front axle of your vehicle.
(not really a big deal because most of the weight is on the rear axle, piece of mind thought)
Do the rear axle without the trailer, then add trailer and weight the rear axle only, this will give you the tongue weight.
Add the trailer and move vehicle ahead and weight just the trailers axle/axles.
This will give you the weight of every thing except the boats weight and if you look at the build tag on the trailer it will tell you what the trailer should weight empty from the factory.

 

[hungupthespikes]

Re: Trailer not level - air bags or taller hitch?

^^^^+1 rbh
If you can't get to a scale:
http://www.continuouswave.com/whaler/reference/trailering/trailerCalculations.html

It also sounds like the shocks are long over due on the suburban. I changed mine out on the 2001 f150 at 170k and made a big difference on the squat. Your lucky, you can go to air shocks, if the tongue weight is high, but replace all four to get a good ride and handling.