Bucking when braking

[Diver-Dave]

I have a '97 3500 with an automatic. When I'm towing my 35' Jayco 5th wheel and apply the brakes, it often starts shaking and bucking when I apply the brakes especially when I'm starting out.



This is really scary since I have to let up on the brakes to stop it from happening and then I might hit something.







I've tried adjusting the trailer brakes at various settings and it seems to happen at all settings.



I know it isn't the trailer since my son-in-law pulled it just fine with his 2001 power stroke.



It almost feels like the trailer brakes are fighting against the ABS.



Has anyone had this happen or know what might be causing this? It scares the wits out of the wife when this happens.

 

[RustyJC]

Dave,



What 5th wheel hitch setup are you using? I had this problem, but it was due to flexing of the adapter post of my B&W turnoverball gooseneck using the B&W companion 5th wheel RV hitch. If you have this arrangement, I can give you a 95% fix. If not, I probably can't be of much help.



By the way, we tow a 2000 Jayco Designer XL 3610RLTS 5ver.



Rusty

 

[rwitt]

Dave,

Is this a problem that just started or has it been occuring for awhile? Just a thought but sounds like a controller malfunction causing the circuit breaker to trip, reset, trip, reset, thereby making the trailer buck from pulsating brakes.

Rich

 

[Diver-Dave]

Thanks for the replies Rusty, Rich. The hitch I have is a RBW Lil' Rocker. The problem has been around since I bought the Fiver in 1998.



Rusty, I never thought the problem could be flexing in the hitch department. Maybe mine's doing the same. What did you do to fix yours? My son-in-law has the same hitch on his Power-Stroke. I'm going to take a close look and compare our hitches and installations since he doesn't seem to have the same problem when pulling my trailer.



Rich, As I mentioned, it's been happening since the day I bought my fifth wheel. You might be right though since I had the controller set up originally to pull a 20' travel trailer and then had it changed to use with my fifth wheel. Any ideas on how to check it?

 

[RustyJC]

Dave,



My fix is unique to the design of the B&W which uses a completely different mounting arrangement than the RBW, Draw-Tite, Reese, etc. 5th wheel hitches that mount on rails in the bed that are bolted firmly to the frame. With your arrangement, I'd check all the bolts, shims, etc. to ensure that there's no "free play" anywhere between the hitch and the frame. If the installer didn't put the shims between the frame mounts and the bed, and between the bed rails and the bed, you could have enough free play to have a flexing problem. Everything must be pulled up rock solid.



I was amazed how little hitch flex would result in bucking during braking. Ours was so bad that it literally threw our Shelties off the back seat and into the floor. I thought the hitch was going to be ripped from the truck! My wife was ready to sell the truck and 5ver, and (to tell the truth) I was about to that point until we finally got this fixed.



Good luck... .



Rusty

 

[Shooter]

At $ 75 to $125 for a new controller, I would not think twice about MY saftey and replace it.

Could you be losing your ground or have a high resistance contact or splice that is not conducting current, or intermitantly conducting or grounding on for and aft bucking ??? . A high resistance connection will show voltage but not carry current.

 

[rwitt]

Dave,

While you're braking with the trailer what are the controller lights doing? With steady even braking you should have the same with the indicator lights on the controller. If they are jumping up and down then the brakes are pulsing. Have you tried manually applying the trailer brakes without the truck brakes to see if it jerks/bucks?

Rich

 

[Diver-Dave]

Well I bit the bullet today and ordered the Jordan brake controller. $145. 00!! I hope it works. After reading some threads on other boards, it seems that the Draw-Tite I have often contends with the ABS in the truck and causes bucking. I'll let all know how the Jordan works.