When I am pulling at speeds of 50-70 mph the truck will intermittenly jerk as if the trailer is braking on its own. The jerkingness has different degrees of jerking, from moderate to just about severe! Keep in mind this is intermittent jerking. I have had the electronic brake controller and truck checked and they are working fine. I have visually inspected the connections to the plug(plugs into truck) and made sure the break away brake switch is frimly seated. The tires are new and can't believe the tires have ANYTHING to do with how extreme this pulling, jerking issue is. I have only had the trailer out 2x since I have owned it and I need to get this problem fixed before I take it back out--especially at high speeds. Does anyone have any clues to help me figure this one out?? Could the outlet in the bed of the truck be 'bad' and causing this? What would make my brakes come on without me pushing on the brakes? Thanks for any advice.
Posted 2010-09-02 3:15 PM (#124318 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Extreme Veteran
Posts: 330
Location: northeast Texas
I am not a rocket scientist, HA HA HA but I would think if your brakes were activating that much that there would be some smoke and/or some wear signs (ie: flat places, ) on the tires? What kind/type of trailer? Loaded or empty? Kind/type truck? Is this a new to you rig? Sounds more like some combo of a load weight distribution hitch bad road thing. Our flatbed gooseneck will do this empty, specially on certain roads. Like I said, I am not a rocket scientist though ! Not enough clicks!
Posted 2010-09-02 3:17 PM (#124319 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Extreme Veteran
Posts: 330
Location: northeast Texas
Oh shoo forgot to add: Hogtownboss I see your wife is going to join us "long riders" this weekend in Decatur. Looking forward to meeting her. Are you coming? I will likely be the last to arrive, around 6:00. I have to work half a day. Boo Hoo.
Posted 2010-09-02 4:30 PM (#124322 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Expert
Posts: 3802
Location: Rocky Mount N.C.
Did you take the trailer plug apart and check inside for a jumper across any of the other terminals over to the blue brake wiring terminal. Those little strands of copper wire can break off and float around inside the plug doing some amazing things sometimes...
Posted 2010-09-02 6:55 PM (#124327 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Veteran
Posts: 201
Location: Lincoln, NE
It seems I remember a discussion on this very topic on this board a while back. You might try searching for it under trailer jerking or jerky ride and see if it comes up.
I've had similar experience even though everything checked out fine. My 2H gooseneck rig did the same thing at a certain speed when on a highway with seams every so many feet.
The most notable difference happened when I drove from Nebraska into Kansas. Nebraska highways frequently have those raised seams and the speed I drive must be just right to hit everyone in a way that starts the rig jerking. It was doing it's rumba down the highway when I drove into Kansas which has a smooth road surface. All jerking suddenly stopped!
Posted 2010-09-02 8:41 PM (#124329 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Elite Veteran
Posts: 736
Location: Western WA
Continuing on with what Flatlandfilly had to say, does the jerking/pulling stop if you step on the brakes or speed up? If so, it may just be that your trailer is not "in sync" with your truck when going over rough roads or joints in the road.
Posted 2010-09-03 8:41 AM (#124336 - in reply to #124318) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
It makes sense what you said about the wear on the tires and/or smoke. I haven't noticed any wear or flat spots. The truck is an F450 and the trailer is a Jamco 13' shortwall, 3 horse. It has done this jerking thing empty and loaded. Thanks for you input!
Posted 2010-09-03 8:46 AM (#124337 - in reply to #124320) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
The brake controller and truck supposedly checked oout fine. But maybe the outlet in the bed of the truck is wacko? Was it easy to find your problem when you were having issues? Was yours on again off again, or was it constant jerking? Mine is intermittent. Thank you for your input!
Posted 2010-09-03 8:49 AM (#124338 - in reply to #124322) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
I did take the end of the plug off and looked at the wires and didn't see anything that looked like it could be a problem. Next , I guess I need to look at the outlet in the bed of the truck. Thanks much for you input!
Posted 2010-09-03 8:57 AM (#124339 - in reply to #124327) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
You have a very good memory! I was the one who submitted an article about the same issue awhile back. Everyone talked about it being the tires and I can't believe the tires are causing such a strong back pulling issue. And as far the road conditions go, the highway was not causing this either. This pulling sensation is backward, not forward and up and down. I also checked my goose to see if it was rocking or jumping and everything was fine there too.
I appreciate your .02cent--it is worth more than that to me.
Posted 2010-09-03 9:08 AM (#124340 - in reply to #124329) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
Nothing seemed to make it stop--not braking or slowing down. Although it would finally go away if I would either slow down or speed up. And sometimes that didn't work either. I did not notice this issue when I was on two lane state roads or highways going at speeds of 55. If it was just me by myself experiencing this problem but I have had two other people with me and they can attest to the severity of it. And we made note of the road conditions--which one time were newly paved.
Posted 2010-09-03 12:57 PM (#124358 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Expert
Posts: 3853
Location: Vermont
I'd have a very reputatable trans shop attach the pressure gauges to the ports and see what's happening to the clutches, as it is being driven.And I'd have the dealer check your ECM unit...just out of curiosity, when was the last time you changed your truck's batteries?
Posted 2010-09-05 12:33 PM (#124423 - in reply to #124358) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
So you are thinking the diesel truck might
be having trany issues? What is an ECM unit? Thank you very much for you input. Oh yeah and I can't remember when the truck had its' battery checked or replaced--have to look in the file. It is an '01, F-450-diesel, and only has 37,000. miles on it
Posted 2010-09-05 12:42 PM (#124424 - in reply to #124359) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
Can I buy one at napa auto parts and change it easily myself? Are they expensive? Remember my truck/trailer did this both with and without load. Thanks for your input.
Posted 2010-09-05 10:40 PM (#124447 - in reply to #124423) Subject: RE: Brake pulling and dragging issues
Expert
Posts: 3853
Location: Vermont
Originally written by tirebiter on 2010-09-05 1:33 PM
So you are thinking the diesel truck might
be having trany issues? What is an ECM unit? Thank you very much for you input. Oh yeah and I can't remember when the truck had its' battery checked or replaced--have to look in the file. It is an '01, F-450-diesel, and only has 37,000. miles on it
Posted 2010-09-08 12:39 PM (#124586 - in reply to #124359) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
Just an f.y.i., found out the F450 diesel 7.3 liter does not have an EGR valve.
But did take trailer to an RV place today and had wiring checked and everything 'looked' good. They did ask me if I took the overdrive off when pulling and I said no. So this could be the problem. zit has never been a problem before but they said that having it on is hard on the transmission. So all I know to do now is drive without the overdrive on.
Posted 2010-09-08 12:49 PM (#124588 - in reply to #124358) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
Had the truck at an RV place this a.m. and all wiring checked out fine. They said I should try pulling without the overdrive on, any comments? The truck is an F-450 diesel, dually, 7.3 liter 2001 with 38,000 miles on it.
Posted 2010-09-08 4:47 PM (#124602 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Elite Veteran
Posts: 720
That model 450 will have a 4.88:1 rear end gearing. It is pretty much topped out at 65 MPH with the O/D on. I can't think I'd want to run it with it off. Customarily you are told to turn it off because the engine RPM goes so low it "chuggles" and that causes a shudder or jumping. That won't be the case here because you should have plenty of RPMs. In my opinion, if your RPMs are 2250 or more when it goes to jumping, you need to look elsewhere.
Posted 2010-09-10 10:04 AM (#124691 - in reply to #124317) Subject: RE: Brake pulling and dragging issues
Expert
Posts: 5870
Location: western PA
You can trouble shoot the problem to specific areas fairly easily. By towing on varying road surfaces, some smooth, some with expansion joints, you can discern whether or not the interplay between the trailer and truck is causing the jerking. If there is no difference, then suspensions, hitches and wheel base concerns can be eliminated.
To determine if brakes are involved, travel the same roads with the trailer plug disconnected. If the trouble persists, it is not an electrical brake issue. However, if some of the mechanical brake components have failed, such as the shoe retract springs or an adjuster linkage, a brake shoe could be temporarly engaging the drum assembly. This can usually be determined by having someone walk beside the trailer as it is slowly being towed. An intermittent, metallic rubbing, or chaffing noise will occasionally be heard.
With a drive train problem, you have three areas of concern. Motor, transmission and axles. Any one can cause the problem. The axles are usually trouble free if they are properly lubricated. A friend of mine experienced some drive train jerking prior to his rear axle locking up. The rear differential cover had rusted, allowing the gear lube to escape, and the gears to eventually run dry. On some of the older positraction gear units, the clutch packages would act up as they wore.
Because all modern engines and automatic transmission are commonly linked by computer controls, it's more difficult to determine which one is at fault. Some problems can only be determined, by whichever service department has the most skilled diagnosticion and equipment.
Once all the easy determinations are made and no fault has been found, it may be time to call in the experts.
Posted 2010-09-11 2:23 PM (#124754 - in reply to #124691) Subject: RE: Brake pulling and dragging issues
Regular
Posts: 72
Location: Hoosierville
Thanks. I will try the pulling slowly while someone walks along side trailer to see if they hear anything. The more I think about it, if the trailer brakes were seizing (for whatever reason) wouldn't I notice wear or dust on the tires? So far they still look good. My actual pull miles on it are right around 330 miles.
I would have to unplug the trailer from my truck and go down the interstate to duplicate what I have previously experienced. That sounds a bit scary to not have any brakes or lights to trouble shoot a question of electrical problems. Supposedly, the electrical has passed all inspections.
I have an appointment with Ford next week to run a diagnostic ? on it and check all fluid levels.
I want to get things resolved so I can safely hit the road and then the trails!!