Lumpy/grabby brakes update

myredracer · 08-16-2012, 12:09 PM

Earlier this year I posted about problems with the brakes on our TT. They have been really pulsating heavily when slowing to a stop. Slowing a bit while at speed, like say from 60mph, is not too bad. But when coming to a stop, the truck and trailer shudders. It has been like this from the day we bought the trailer last August.

We rebuilt the front brakes on the truck with slotted rotors and quality metallic pads. Truck stops on a dime now, but no change in the trailer braking.

Installed a new Prodigy P3 BC to replace the original POS Draw-Tite one installed by the hitch shop. Not much improvement, but some. Currently have it set to 3.5 as recommended by Tekonsha by phone.

Today I took the trailer into the dealer to look at. We have about 7 days left on the 1 year warranty. I am expecting them to say it's not a warranty issue and am not sure how I am going to fight them on this if needed. I'll take them to court if I have to.

If the trailer brakes need repair, I sure don't want to pay them their $125 per hour shop rate. I talked to the local independent RV repair shop and they said it would cost around $350 for them to rebuild two wheels, including turning the drums. He said their might even be an issue with the bearings.

I have to wonder if the pulsating trailer brakes contributed to the failure of the front brakes on the truck (one caliper seized up), but I have no way of ever proving this.

On a side note, why is it when you make an appointment to take an RV into a dealer they end up saying the need to keep it for a week? Why can't they just get you in on the day when they will do the work??? Last time I took it in, they ended up keeping it for over a month last Nov. And the last time I took it in, they put a nice dent in the front but I didn't notice it for a few days afterwards and could not prove it happened on their lot. This time I did a walk around with them. Since I am in a bad mood about the brakes, I will also say that this is the 3rd time in for warranty work and will be the 3rd time I am trying to get them to fix the bathroom door. Grrrr......

I will post about how the brakes are after they get fixed.

Dave_Monica · 08-16-2012, 01:25 PM

Quote:

Originally Posted by myredracer

Installed a new Prodigy P3 BC to replace the original POS Draw-Tite one installed by the hitch shop. Not much improvement, but some. Currently have it set to 3.5 as recommended by Tekonsha by phone.

There should be a calibration procedure in you operating instructions from Prodigy. Setting the BC at 3.5 seems very low...I seem to recall that they recommend an initial setting of 6.0. Follow the procedure in the operating instructions but be sure to have the brakes warmed up first before calibrating.

Here's a link to the operating instructions...

http://www.tekonsha.com/content/down...ion/N90195.pdf

Dave

myredracer · 08-16-2012, 01:47 PM

Dave, thx for the PDF link. Already have that though as it came with the package.

DW talked to the Prodigy folks on the phone while we were pulling the trailer. Discussed all the setup procedures and for the weight of our TT (about 5,000 lbs loaded) and other pertinent info., 3 to 3.5 is what they recommended. Also discussed the setup in detail with the shop in Oregon who installed it.

It just feels like upon every revolution of the wheels, something is dragging or catching. If I modulate the brake pedal and let up a bit so the pulsating stops or isn't as strong, and the truck + TT still needs to be slowed down, if I put more pressure on the brake pedal again, the pulsating can get even worse. But I have to stop.... I know little about trailer brakes but at this point I am guessing there is a warped drum or two. This can't be good on things like wheel bearings either.

lmcleister · 08-16-2012, 01:57 PM

Check the Brake Controller BOOST setting. Might want to try pulling with BOOST setting off before tearing into the brake drums.

Dave_Monica · 08-16-2012, 02:02 PM

I read your post again...do I understand that when stopping, you have pulsations that you feel in the brake pedal of the truck? The campers brakes are electric and wouldn't cause pulsations felt in the truck's brake pedal.

Dave

donn · 08-16-2012, 02:25 PM

Curious, did you ever adjust the brakes on the trailer?

myredracer · 08-16-2012, 02:32 PM

donn, no have not tried adjusting the brakes. Since this problem has been like this since brand new, could this be a factor? Wouldn't adjustment just improve the effectiveness (operating force) of the drum brakes? Perhaps the brakes left the factory waaay out of initial adjustment?? I dunno.

Anyone have a link to something that shows an exploded diagram of how trailer brakes are designed? Trying to get a mental picture of what the internal components look like. Did a search one day and couldn't find anything.

myredracer · 08-16-2012, 02:34 PM

No, there is no pulsating feel to the brake pedal in the truck. I've tested on a flat parking lot by turning the BC off and the truck comes to a smooth stop. Definitely the trailer brakes.

"Pulsating" is the only word I can think of that describes what it's like. It's definitely related to the tire revolution speed. As I say, it's as if one or both drums are out of round and the shoes grab harder upon each revolution. It's also like a shuddering and you can feel the truck pulsating/shaking.

Won't hear from the dealer until early next week as to what they find. Not a good time of year to have an RV into the shop as we have more camping coming up.

myredracer · 08-16-2012, 03:05 PM

Also, have tried different boost settings with no basic improvement. Currently set to B1, IIRC.

OldCoot · 08-16-2012, 03:08 PM

Quote:

Originally Posted by Dave_Monica

I read your post again...do I understand that when stopping, you have pulsations that you feel in the brake pedal of the truck? The campers brakes are electric and wouldn't cause pulsations felt in the truck's brake pedal.

Dave

OP stated that truck works fine after replacing rotors, etc. I would imagine the trailer drums are warped and will need turning or replaced. If the drums are warped, you will feel the pulsating in the truck, just not on the pedal as you say, they are electric and have no effect on the truck brakes themselves.

Happy Vibe · 08-16-2012, 03:13 PM

I had a very similer issue with my brakes. Worked fine at speed over 10 MPH but that last 5 MPH to stop I would get pulsating. The only way I could get it to stop was to set the Boost to zero (no boost) and adjust my voltage setting to around 6.5. Sometimes under very light braking at low speed I still get a little pulsing but nothing like it was.

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