Major Tow Problem

J

Jim Innella

New member
Can't believe this is happening , but would greatly appreciate any suggestions. Used to tow my IT7 with a 2001 Ford Expedition and a 20' x 7' wide enclosed trailer. I put air bags in the rear and we tracked straight and solid with 45 PSI. Just bought a 2004 Expedition same options(5.4 Lt) Standard tow package. Also upgraded to a 26'x 8.5' wide trailer made by the same company as the first. This one has 12500 axles first rated for 7000. On the first tow I realized I needed to install the airbags or drive on 3 lane highways with no one else around. Could not control the trailer over 45 mph. Went to get the air bags installed and found out the 04 has an independant suspension with no where to put the bags or air shocks. Trailer guy recommended to put on some eaze-lift trailer leveling bars. Cost $400 and now I can get to 50 mph before I have to drive back and forth across the road out of control. I have tried different tension on the chain tension devices but still no good. Called Ford and asked how come my 8950lb tow rated Expedition can't tow 6000lbs in a straight line. I think the problem has everything to do with the weight on the rear axle lightening up the front end but even putting the car towards the rear of the trailer doesn't help. The Ford dealer is checking into exchanging my Expedition for a 2500 or 3500 but I can imagine what my loss on that deal will be. I am pretty desperate right now and would look forward to hearing anything that might solve the situation .
Thanks
Jim I
IT7 #60
 
Wow, I'm surprosed that the IRS is not towing well for you.. I've heard that it is a better package...
A few thoughts to check.
1) Ball height.. IFIRC, the new Ex is lower than the old by several inches. maybe you don't need that drop hitch anymore.
2) a 26 fotter is a large trailer. Mine is a 28 on an Excursion. If you don't load it properly, it can still fight you.
3) Does the butt on the expedition droop? If so, how much spring to you have in the bars, and what bar rating do you have (500,750, of 1000 lb). If you can latch the bar with anything less than a 1 ft pipe, you probably need more tension.
4) I have air sprigs as well and can agree on their effectiveness. However, you could always use air shocks . cheap and effective.
5) Have you weighed the tongue weight?

One assumption for me would be that you absolutely MUST contol rear droop as I'm sure the IRS has some range of motion tow/camber changes which could be aggravating your problems.
 
BTW,
I know it's a thread hijack, but..
I have my tow rig for sale..
28 ft enclosed $3000 cabinets, tire rack.

2002 Diesel Excursion. Air bags, Tekonsha brake controller, Bullydog chip, Bilstiens, rear sway bar. 72K miles. Email me if interested.

Have pics of both
[email protected]
 
Originally posted by Jim Innella:
...even putting the car towards the rear of the trailer doesn't help. ...
Click to expand...

I would be worried that this might make the problem worse rather than better. Before you do anything, make sure that you have the correct amount of (positive) tongue weight.

Kirk (who crashed two trailers due to bad assumptions about the aforementioned issue)
 
Jim,

6000# for that rig, w/ the car in it, seems light. My 10,000# GVW 24' Haulmark weighs 3350# empty. I didn't take it across the scales, but I figured that it was between 6000 - 6500 w/ the car/gear/spares/etc. in it.

But, I'm w/ everyone else, you need to make sure your ball height and tongue weight are set properly.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608
 
Are the leveling bars Sway Control type? After you do check Tongue weight Ball Height then perhaps a sway bar will still be needed. I sure would be back at trailer Dealer and be talking to them to get the problem straightened out after all you spent a barrel of money with them. The leveling bars should have had some basic instructions with them for setup and adjustment. There might be a problem with the trailer axles that needs to be checked. Easi Lift makes an add on sway control thats an easy install. Hope you can get corrected. T Weaver

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Tom Weaver: Logistics & Technical Support Manager IE truck driver for 1980 RX-7 ITA #63
"Hemi haulin' Rotary"
 
Kirk is right, I am betting you don't have ENOUGH tounge weight...

Load levelers AND Anti Sway control is optimal. My 2001 Expedition has the tow package and has factory load leveling so anti-sway is all I need with the right tounge weight. Try moving the car toward the front.

AB

------------------
Andy Bettencourt
06 ITS RX-7
FlatOut Motorsports
New England Region #188967
www.flatout-motorsports.com
200_06_checkered.jpg
 
If scales to check tongue weight are not available, I would do the following:

1. level trailer and measure height of ball pocket. adjust height of ball on vehicle to same height plus or minus 1/4".

2. hook up trailer fully loaded but without torsion bars and adjust car position so the tongue droops about 3".

3. drop however many chain links are necessary to bring tongue back to normal height. would only use 1000# torsion bars for this application. carefully road test. you should, with this process, have approximately 300# tongue weight. adjust car position for more if needed, but always use torsion bars to level rig after movement. thailer should be parallel to the road, and truck should sit normally as if unloaded.

good luck, chuck
 
Another vote for not enough tongue weight, with an explanation why. Simple physics.

Most folks tend to load their trailers to where it "looks right" without pushing down on the tongue too much, but that's wrong. That tongue weight is there for a reason. A general rule of thumb is 10% of the trailer weight should be on the tongue, and manufacturers design the trailers to locate the CG based on this guideline. If that depresses the back of the truck too much then you need to attack the rear suspension of the tow vehicle or use levelers as Chuck suggested, not reduce the tongue weight.

The reason is center of gravity, center of rotation, and friction. Think of a shopping cart. The rear wheels of a shopping cart do not caster. If you try to push a shopping cart backwards the cart will try to spin around on you. The reason for this is because the center of gravity of the shopping cart is behind the rear wheels when you're pushing it backwards, and that center of gravity always wants to be in front of the point of friction/rotation (the rear wheels.) If you stay with it you can adjust the cart to keep it going backwards but it's an unstable system; if you do not constantly adjust it the cart will flip around to put the CG forward of the rear wheels.

Your trailer is the shopping cart: your wheels do not caster. If the center of gravity of the trailer is behind those wheels, then the trailer will always try to rotate to put the CG in front of the wheels. The swaying you're feeling is the tail literally wagging the dog: your trailer is trying to rotate to put the CG forward and is moving the truck around. That's the swaying action you're feeling.

The fix is easy: get the CG of your trailer in front of the axles. This can mean moving the car forward, putting additional weight on the nose of the trailer (tires, tools), or in extreme cases modifying the trailer to move the axles backwards.

Until you get that CG forward your shopping cart will continue to try and rotate on you, and that force will act on your truck. If you've got a hell of a rig, like with duallies and a lot of frame weight, your truck might be able to mask the problem, but until you load it right your trailer will always be trying to fight you.

In the absolute worst case, if your trailer ever came free a properly loaded trailer will trail straight, the breakaway brakes will engage, and if you're lucky it will skid to a halt straight ahead. A poorly-loaded trailer will act just like the shopping cart and swap ends, probably roll, and will make a big mess while taking out some folks behind you. You *will* be late to the grid.

Move the weight forward.

Greg
 
I towed my 20ft Wells with two different Expeditions (97 and 99)before I traded up to the Excursion.
First what tires are on your Exp and then what air pressures are the tires set for. Ford puts a lite-weight tire on the Exp which is barely rated to hold up the weight of the truck, much less a load. This is particularly bad with the 17" package. I ended up with Michelin Pilots with V rating to get the tow "feel" that I was comfortable with.(When I turned the Exp in at the end of the lease, a friend bought the Pilots for his Exp) You can trick the tires by increasing the air pressure to >60#. Otherwise the tires just push out on the sidewalls.
I would bet that there is not enough ball weight too. As previously stated, a foot or less can make a big difference in the balance of a trailer. I always towed with the bars so I dont know what it would be like without them.
IMO the wheelbase of the Exp may be too short for the trailer that you are towing and you may need to trade up. There are incredible deals out there in late model Excursions. YMMV
 
Greg nailed it. The CG is behind the axles, so it is trying to swap ends. Move the load forward.

Like last summer when I went to the local garden supply place to get some bark chips for the wife's weekly project. The guy with the front end loader drops the whole load near the tailgate of the utility trailer. It was a wild ride home.

Gregg
 
Move the car to the "FRONT" of the trailer and try it again. Like the others have said, you have too little tongue weight if the trailer starts to "wander". Also, does this condition happen only when "coasting" or also under acceleration and braking?

I had this problem a few years ago, when I bent up the IT Scirocco, and had to put in on the trailer "backwards". I could only manage about 45 MPH. It was a long tow home.

------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit (Bent)
http://linerud.myvnc.com/racing/index.html
 
while getting the right cg on the trailer is the key, another big factor is the truck's tires. i had some old firestone steeltex's on my tow vehicle (k2500 suburban with big block towing a 20ft wells and its car). tires sucked if you wanted to stop, but otherwise were very stable when towing. one blew out so i got some new pirelli scorpion (load range e) truck tires. now the thing stops great, but won't go in a straight line with the trailer hooked up. given that i didn't change the trailer setup, looks like the pirellis just have too soft rubber in the tread blocks to control the additional load.

personnally don't recommend either of these tires....

marshall
 
Thanks to everyone. I did try moving the weight to the front and it made a lot of difference. I played around with the car placement then carefully added spare tires , tool boxes ,etc. and can tow pretty straight at a little over 70. The idea about the tires being thin walled has merit also I do get some droop on the rear of the vehicle and the back tires look low. I have added about 5 lbs to all 4 tires. Once I moved the weight up front the leveling bars I installed also seemed to make a difference. I guess the best lesson for anyone with a tow sway problem is to try and move the load forward. My original thinking was to place it back further to reduce the tongue weight and lighten the load on the rear of the tow vehicle but obviously that logic was flawed. Thanks again to everyone who offered advise.
Jim I
IT7 #60
 
Good to hear, Jim but add more air to those stock tires for the Exp. Those things are "P" rated and Ford did not intend you to tow with the Exp as equipped. Better yet, replace them with better stuff.
Remember the mind set that towing is the most dangerous part of racing. YMMV
 
And while adding 5# may "look" right, remember not to exceed the max tire pressure at max load rating on the sidewall of the tire.
 
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