CRAZY sway when brakes applied - Fiberglass RV


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-16-2011, 11:31 PM   #1
Member
 
Trailer: Bigfoot 21 ft
Posts: 30
CRAZY sway when brakes applied

So, you know the drill - get home from work, run around like an idiot, packing the bikes/toys/dogs/beer/etc etc etc. All is done and we were off to the Shushwap.....

Hit Armstrong (coming from Vernon), and I applied the brakes and the trailer immediately violently started swaying - fishtailing - back and forth. Obviously we pulled over, onto a side road.

My first thoughts were that I had a flat tire? Nope. nothing. So drove along this side road to test it out. Sure enough, did it again - only at certain speeds. And when foot taken off brake and gas, still sways excessively till at a stop. It almost feels like the thing is going to rip off the hitch!

I am towing a 21.5 Bigfoot with a f350. I usually have my brake controller (stock) at 5 - 6 depending if water loaded. Today I had it at 5.5. I tried lowering it down to 4 and still same thing happening.

We turned around, not risking any damage to trailer / ourselves.....I figure brakes must be not braking evenly or something. Will make some calls to some brake shops in the AM then try to head out again.....

Any suggestions??

Thanks

Simon

PS I forgot to mention that yes, I do have sway bars....
__________________

__________________
Simon A is offline   Reply With Quote
Old 06-16-2011, 11:50 PM   #2
Senior Member
 
floyd's Avatar
 
Name: Floyd
Trailer: 2004 13 ft Scamp Custom Deluxe
IllAnnoy
Posts: 6,048
Registry
tongue weight?
Broken brake wire causing only one side to grab?
Bad seal with grease in the brakedrum on one side??
Cracked frame or axle mount, which can cause the axle to move when brake is applied?
Do you have a torque flex type axle?
If it is leafs, then a broken leaf or shackle, or axle U-bolt?
__________________

__________________
floyd is offline   Reply With Quote
Old 06-16-2011, 11:58 PM   #3
Senior Member
 
Perry J's Avatar
 
Name: John
Trailer: 16' Casita
California
Posts: 975
Send a message via AIM to Perry J Send a message via Yahoo to Perry J
I think you don't have enough tongue weight.
You should have 10% to 15% of the gross trailer weight on the tongue.
John
__________________
Perry J is offline   Reply With Quote
Old 06-17-2011, 12:04 AM   #4
Member
 
Trailer: Bigfoot 21 ft
Posts: 30
I have been towing this trailer with this truck for over 4 years now. Over mountain passes, glaciers, highways, winter, summer, etc etc etc. Never an issue 'till now.

I will check wiring in AM. By the time we got back home it was dark. Axle, frame, u-bolts all seem OK. Tows fine just when brakes applied it does this. And seems to only do this when at a certain speed ("sweet spot") - roughly 60 km per hour.

I am leaning towards the wiring issue. because IMO it would make sense if only one side was 'grabbing' then this would happen.
__________________
Simon A is offline   Reply With Quote
Old 06-17-2011, 07:57 PM   #5
Senior Member
 
Donna D.'s Avatar
 
Name: Donna D
Trailer: Escape 5.0 TA, 2014
Oregon
Posts: 24,433
Simon, the palms of my hands got sweaty just visualizing this. Hope you get it figured out soon and will feel comfortable once again towing your Bigfoot!
__________________
Donna D.
Ten Forward - 2014 Escape 5.0 TA
Double Yolk - 1988 16' Scamp Deluxe
Donna D. is offline   Reply With Quote
Old 06-17-2011, 09:33 PM   #6
Senior Member
 
Name: Dave
Trailer: Bigfoot 25 RB and Bigfoot 21RB
British Columbia
Posts: 1,143
Sway

Of course, if it continues to be a threat to the life safety of you and your family, I will rescue you by taking it off your hands - just to save you of course!

On a more serious note - there are a number of things that could cause this- ranging from a brake lining coming unbonded from the shoe and wedging itself at certain speeds, to a brake magnet that this not fully engaging fully (possibly a bit of grease on the facing of the drum). A spring hangar could be broken or a bushing is shot. As noted earlier a wire that is shorting could do it. If it is brake failure on one wheel or one side, it would likely not sway back & forth - more likely just pull to one side only - but I have been wrong before! (maybe it does just pull to one side and then "rebounds" against the hitch?)

Something as "silly" as a castel nut coming off, allowing the hub to move on the spindle?

From your description, it is hard to tell, but is it possible that an axle is actually moving on the spring, relative to the trailer frame?

However, having been a trailer dealer (for medium duty construction flatdecks in the 7 - 12,000 lb GVW range) and having had the occasional trailer make a serious attempt to pull out and pass me at speed, I can relate to the feeling. It is a real sphincter-tightener!
__________________
BCDave is offline   Reply With Quote
Old 06-17-2011, 10:17 PM   #7
Senior Member
 
Mike Magee's Avatar
 
Name: Michael
Trailer: Li'l Hauley
Oklahoma
Posts: 5,143
Here's a test to try. When traveling at that 'certain speed,' apply only the trailer brakes (not the truck brakes). If sway occurs, this would seem to indicate a problem with the trailer brakes (and the reverse situation, applying truck brakes without trailer brakes, should be sway-free). If not, look for other causes.
__________________
How much time do we have left? 2 Chr. 7:14
Mike Magee is offline   Reply With Quote
Old 09-27-2011, 12:57 AM   #8
Member
 
Trailer: Bigfoot 21 ft
Posts: 30
Update (long over due):

Long long long story short ended up being both my leaf springs (mains) had snapped! Only noticed when I took one of the wheels off.

put new leaf packs in (used). All good. Still peaved multiple mechanics / rv techs had no idea what the problem was....
__________________
Simon A is offline   Reply With Quote
Old 09-27-2011, 09:04 AM   #9
Senior Member
 
Emily R.'s Avatar
 
Trailer: 1975 Trillium 13 ft (Fluffer-Nugget)
Posts: 365
Registry
So glad YOU noticed it...Sorry you had to pay to have the mechanics find nothing. Glad everything turned out okay.
Cheers! Emily
__________________
Emily R. is offline   Reply With Quote
Old 09-27-2011, 09:55 AM   #10
Senior Member
 
floyd's Avatar
 
Name: Floyd
Trailer: 2004 13 ft Scamp Custom Deluxe
IllAnnoy
Posts: 6,048
Registry
Quote:
Originally Posted by Simon A View Post
Update (long over due):

Long long long story short ended up being both my leaf springs (mains) had snapped! Only noticed when I took one of the wheels off.

put new leaf packs in (used). All good. Still peaved multiple mechanics / rv techs had no idea what the problem was....
Thanks for the update,It doesn't always happen,and it's nice to hear back on how the story ends.
__________________

__________________
floyd is offline   Reply With Quote
Reply

Tags
brakes


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Stealth Technology applied to Boler Air Conditioning Install Markz Modifications, Alterations and Updates 11 07-10-2010 01:12 PM
R.V. Crazy Chris L. General Chat 5 11-18-2007 08:01 PM
Trailer Brakes And Sway Bar davefryg Problem Solving | Owners Helping Owners 29 11-02-2006 09:59 PM
Trillium 4500: Brakes? Sway control? Air shocks? Legacy Posts Problem Solving | Owners Helping Owners 9 05-30-2003 07:11 PM

» Upcoming Events
No events scheduled in
the next 465 days.
» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 05:19 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.