I took the time today to stop at some scales and weigh my rig. I have a 2000 excursion and pull a 30 foot trailer with a race car inside. I am looking for advice on the math and if I need to change something, what should it be?

- Is my tongue weight correct? I can move the car to change the weight distribution.
- Should I tighten up a link on the weight distribution hitch?

-Excursion only
Front axle = 3660
Rear axle = 3880
Total = 75400

-WithOut Weight Distribution hooker up
Front axle = 2900
Rear axle = 6200
Trailer = 7840
Total = 16940

-With WD hooked up
Front axle = 3180
Rear axle = 5800
Trailer = 7940
Total = 16940

-Calculations
Trailer weight = 16940 – 7540 = 9400
Tongue weight WithOut WD = 2900+6200 = 9100 - 7540 = 1560
Tongue weight With WD = 3180 + 5800 = 8980 -7540 = 1440

Thank you in advance

 

I just ask this out of curiosity, how does the car sit in the trailer in relation to the axles?

 

Only thing that you may want to change is the tongue weight. You have approx 16% (1500) on the tongue, and that is a bit much for the X. Re-arrange stuff in the trailer and see if you can come up with a 1200lb tongue weight. Should make it a little more stable.

Bob

 

The car sits about 2/3rds behind the center of the dual axles on the trailer. It's a 30 foot trailer. The trailer axles are probably 2/3rds back from the front of the trailer body as there is a designated work space up forward. Its been tough to get it worked out.

The Car inself weighs about 2,700 pounds

 

Sounds like i need to place the car a little more towards the rear. Unfortunately I didn't do very well in physics....any guesses on how far back I need to move a 2,700 pound car to take 300 pounds off the tongue?

 

Physics is easy! Here's how you do it:

1) Take your complete rig to the scales; alternatively, get one of those scales set up to measure tongue weight.

2) Weigh everything. Move the car back about 6 inches. Check the weight again.

3) Repeat the steps above until you get exactly the weight you want, then strap the car down and mark your spot so you know where it goes in the future.

Sure beats 6 hours of math!

However, if you want to figure it out without actually taking your rig anywhere, you're probably going to have to pull out the tape measure and give some more accurate measurements of distance from ball to trailer axles, ball to COB of the car, and probably the wheelbase of the car. While you've got the tape out, horizontal distance from COB of the car to midpoint between trailer axles (if double; center axle if triple) might be needed too.

But what the heck do I know, my degree's in economics, but I stayed in many Holiday Inn Expresses.

 

Do what Husky44 said ^ up there.....

 

Rackeu-

Send me a PM with your email address and I will send you a rather complex and comprehensive spreadsheet that I made to answer just this question.

 

Hmmm...... perhaps both would work. It is a lot of dinking around moving the car back and forth and difficult to do without spending the afternoon doing it. However, if I set the car back a foot when I load it today and then get a weight reading two things can happen.
1> I could have stumbled upon the correct placement and that's it or
2> I would have a "formula" for how much the tongue weight reduced when I moved the car a foot and from that may be able to calculate any adjustment needed.

 

Thanks housedad it is a real beauty. It will take a while for me to figure it out. Thanks again.

 

I reweighed today my rig on the way back from the track. I moved the car about one foot back in the trailer which should reduce the tongue weight. I also tightened up my WD hitch to see what would happen.

Excursion only
Front axle = 3660
Rear axle = 3880
Total = 7540

WD engaged (4th link) with car forward (as in the first post)
Front axle = 3180
Rear axle = 5800
Truck total = 8980
Trailer = 7940
Rig Total = 16940

WD engaged (4th link) with car moved one foot rearward
Front axle = 3180
Rear axle = 5520
Truck total = 8700
Trailer = 8120
Rig Total = 16820

WD engaged (5th link = tighter) with car moved one foot rearward
Front axle = 3340
Rear axle = 5280
Truck total = 8620
Trailer = 8180
Total = 16800

If I understand everything correctly, it looks like I have taken about 300 pounds off the tongue weight.

Also it appears that the 5th link is the way to go as it gets the front axle closer to its baseline weight load.

 

I went to my county dump about a week ago. They weigh you in and out. My Ex was 7,880 with a 1/2 tank.

 

pretty funny

 

The major hitch makers design them so that when the unit is properly set for spring angle and ball height, it should be right on link five. The entire procedure you go though for adjustments and installation is dependant on this.

The reason is to ensure enough chain is present to effectively clear the springs from hitting the trailer frame.

 

rackeu,

You still need to work to get that front axle closer to its unhitched (i.e. baseline) weight of 3660.

What type of WD hitch are you using?

Most have provisions to 'tilt' the hitch head which effectively gives you more weight transfer for the same chain link position.

As you sit right now with what you are calling 5 links...you are still 320#'s lighter on the steer axle of your Ex...this can make for a very un-nerving towing experience.

Also you want to strive for 12-13% tongue weight of the loaded trailer...it appears that your loaded trailer goes roughly 9300#'s...I see some variation in your numbers for TOTAL weights and that doesn't make sense to me...so I assume that the difference is you being on/off the scale for some readings? Moving the car fore and aft won't change the 'combined' weight but will change which axles it shows up on...

So lets go with 9300#'s as a LOADED trailer weight...you need to shift the car fore and aft to get you right at 1200#'s (or 13%) of tongue weight for a natural anti-sway towing experience...

However...seeing as how you have a 2000 Ex...you need to check your receiver rating as some earlier model Ex's came with a 1000# in WD mode receiver versus the later 1250# WD mode receivers...check what you have.

Once you get the tongue weight set at the right number...THEN you can tweak your WD setup to return that steer axle to its unhitched weight. Having that much weight removed from your front axle will cause you to have to put unnecessary steering inputs in to drive the Ex...especially on windy days.

So...let's say you have your 1200#'s of tongue weight set...

If you are curious...to determine the tonge weight...is real easy.

You have your baseline front and rear axle weights (3660 and 3880 respectively). Pull onto the scales and position the car until your rear axle is in the 5600-5800# range. You can then make small tweaks as needed like this.

Your FRONT axle is UNLOADED by some amount and it is showing up on the REAR axle which compounds the math just a little bit. Your rear axle baseline weight is 3880 + 1200 = 5080 plus whatever weight is currently removed from the FRONT axle. Play with the car in the trailer until the rear axle weighs whatever the sum is for the weight removed from the FRONT axle added to 3880 plus 1200#'s...does that make sense?...it is somewhat trial and error but the numbers are pretty straight forward.

In your first example above here is how the numbers work out.

Front hitched but NO WD = 2900#'s. You have therefore REMOVED 760#'s from the FRONT axle

Rear hitched but NO WD = 6200#'s. You have therefore ADDED 2320#'s BUT some of that is the weight shifted from the FRONT axle.

The TRUE tongue weight is 2320 - 760= 1560 (same number you came up with previously).

So...shift the car fore and aft until you solve this equation/approach for a 1200# tongue weight.

NEXT...now you need to start working on the WD.

You have your baseline front axle weight you are striving to return to...and you are still IMO a ways off...

Hitch head tilt is your friend...I'm not sure what style hitch head you have though but most will allow some type of tilt this way as Bion said...you have sufficient chain link to insure that you don't get into a bind situation with the WD bars and trailer frame...Top mounted ball couplers are notorious for bind situations with WD bars so if your trailer is a top mounted ball coupler...you need to watch for binding issues...I've seen people that don't pay attention to potential binding issues blow out the side of their Reese trunion style hitch head when the WD bar presses up against the trailer frame and imparts HUGE stresses/forces into the trunion area causing the hitch head to explode out the side due to the forces...best advice is to set up your hitch head to allow for compound tight backing maneuvers...

At this point...I think you need to get the tongue weight as close to 1200#'s as you can once you verify your receiver is rated for 1250#'s that is.

Next...work the WD to get that front axle closer to the 3660 unhitched weight and I know you will be much happier towing down the road...especially when the weather kicks up and starts blowing hard or some tractor trailer comes blowing by you at 80mph and hits you with a wall of wind...having that steer axle firmly planted on the pavement will be critical then...

If I have confused you in any way...please let me know and also if you have any questions...keep them coming!

There is NO reason anyone should ever have a poor towing experience in an Excursion...

Good luck,
Joe.