Posted 2007-07-27 9:02 AM (#64478) Subject: brakes and pin weight questions
Extreme Veteran
Posts: 385 Location: washington
Last week I was coming down a significant mountain pass, pulling my steel 2-H GN; when I applied the brakes to slow down, the truck shimmied a little. That has never happened before. I took the truck in and the brake shop said the brakes and rotors were fine. Next week the trailer is going in for a brake check. Anybody else have this happen? (driving a Chevy 3/4 4x4 6.0L with xtra cab-plenty of towing power for this rig.)
Also, is pin weight typically approximately 1/4 of the scale weight of the trailer? The registration for my trailer states the weight at 4500 lbs, which of course is empty with no mats, etc. With mats, and the do-it-yourself insulated and finished tack area, I am guessing the empty trailer is closer to 5200 without horses. I haul 1 horse, usually in the back stall because the first stall has hay, grain, water and a portable corral. Just wondering if the pin weight would be 1/4 of a fully loaded trailer.
Posted 2007-07-27 2:22 PM (#64495 - in reply to #64478) Subject: RE: brakes and pin weight questions
Expert
Posts: 2828 Location: Southern New Mexico
I was told that the average pin wt is 18% but that it varies from trailer to trailer. It depends on the length of the trailer and axel placement.
Take your truck/trailer to a scale, fully loaded, and weigh them. You can weigh just the truck while hooked to the trailer, then weigh the truck unhooked from the trailer. Subtract the unhooked weight from the hooked up weight and you will get the pin weight.
Posted 2007-07-27 5:08 PM (#64500 - in reply to #64495) Subject: RE: brakes and pin weight questions
Expert
Posts: 1391 Location: North of Detroit, MI
Ditto what Terri said... in fact, my owner's manual (which I think was written for the BP version.... rather than the GN but who knows) says only 10% of trailer weight to consider as pin/ tongue weight.
I err or the side of horse-sense and figure it at 20%. : )
Does your tow vehicle have ABS / Anti-lock brakes? I'm wondering if it may have sensed a "skid" situation and was trying to accomodate that?
I know that my Tekonsha Voyager brake controller requires a small "fix" to one of the electrical boxes in my truck because I have ABS... I'm not sure if this "fix" then bypasses the ABS sensor? OMG - can you imagine having horses in the trailer and you apply your truck brakes and they start "pulsing"/ pumping and what that would do to your trailer and/or trailer brakes? If you've never felt it, it's a VERY rapid on and off... not like you would do yourself... It's been "lovingly" termed "having a foot massage" here in Detroit.
Posted 2007-07-27 5:43 PM (#64503 - in reply to #64500) Subject: RE: brakes and pin weight questions
Expert
Posts: 1416 Location: sc
Originally written by gabz on 2007-07-27 6:08 PM
I know that my Tekonsha Voyager brake controller requires a small "fix" to one of the electrical boxes in my truck because I have ABS... I'm not sure if this "fix" then bypasses the ABS sensor? OMG - can you imagine having horses in the trailer and you apply your truck brakes and they start "pulsing"/ pumping and what that would do to your trailer and/or trailer brakes? If you've never felt it, it's a VERY rapid on and off... not like you would do yourself... It's been "lovingly" termed "having a foot massage" here in Detroit.
really nothing should happen, if the abs is doing its thing your foot is on the brake which in turn tells the controller to apply the brakes. if its a timed unit it will never know the difference, if its proportional (prodigy, and your voyager i believe) the controller should apply less brakes to the trailer as less stopping will be sensed by the controller. ive never noticed anything screwy in my "test" stops.
Posted 2007-07-27 11:23 PM (#64516 - in reply to #64503) Subject: RE: brakes and pin weight questions
Extreme Veteran
Posts: 385 Location: washington
The shimmy was more like a vibration, noticable and alarming, but not the ABS from what iI could tell. I've had my ABS engage before and know what that feels like. This was a vibration that stopped immediately when I took my foot off the brake. I wasn't braking fast/hard, just applying firmly to slow down for a curve way ahead, wanting to take it easy for the horse's sake. I ended up downshifting (automatic) and letting the tranny do more of the work, which is how I drove the rest of the way down the the next 4 mountain passes I crossed :) I just assumed it was my brakes. I'll find out next week if it's the trailer. I had come over the same pass on the way to a ride and the truck didn't respond that way when braking, just on the way home. Sure got my attention !
Posted 2007-07-28 2:21 PM (#64533 - in reply to #64478) Subject: RE: brakes and pin weight questions
Regular
Posts: 96 Location: Massachusetts
I’d have someone check the front end of the truck, especially for bad ball joints or tie-rod ends. Front brakes do approximately 75-80% of all the braking. The weight of a trailer will place extreme forces on the components of the front suspension when braking and traveling downhill. That would be the first thing I would check.
Posted 2007-07-29 8:19 AM (#64557 - in reply to #64478) Subject: RE: brakes and pin weight questions
Expert
Posts: 1205 Location: Arkansas
We had a rotor warped, same thing, also the interior of the front brake lines are lined with rubber on ours, and that collapsed,making the front brakes pretty pitiful...you need a good honest mechanic (don't we all)
Posted 2007-07-29 5:10 PM (#64598 - in reply to #64550) Subject: RE: brakes and pin weight questions
Extreme Veteran
Posts: 385 Location: washington
I took the truck to Les Schwabbe - they've always been good at what they do and they checked the brakes and rotors. They could've made some money off me that day, if they had said it was the brakes and or rotors, so I had no reason to doubt what the mechanic said. The truck has not done that since, so I don't know what the problem is/was. The trailer goes in this week for a service / brake check.