Trailer Brake Gain on GM trucks

[hatstomper]

Could someone please, with a newer GM and approx same trailer as us, tell me what your trailer brake gain is. On our other GMC it was set at 4.5 for a 28RKBS approx. weight of 9500lbs. The new trailer is giving us brake grief and to get anything that holds the trailer at a stand still I have to have the gain at 8. It's been back to the dealer and they have been a little helpful but not much. My understanding of the set up is to drive 30kph to 40 kph to set up and have done that. My concern is that even at a 10 setting I cannot lock up the trailer brakes

[cyclepuck]

The rv dealer set mine up at 4.0 & seems to be about perfect. Tv is a 2012 1500 & trailer is around 7600lbs. They said most of the gm brake controllers they set is usually 3-4.

[MIKE44460]

From the GM service manual, with the motor running, gain set to 10.0, have someone apply the trailer brakes manually, voltage at the plug, ground to brakes, 12-14 volts

[hatstomper]

Thanks Mike, that was checked and the voltage was fine.

[Dave_Monica]

The issue could be that the brakes on the camper need to be adjusted.

Dave

[TURBS]

That's what I was thinking Dave.
Trailer brakes out of adjustment .

[hatstomper]

Just picked it back up....again...from the dealer. Says all is well. I think not but I'm at wits end here. It is better then it was but not as I think it should be, as I said in the first post.

[TURBS]

Mine were that way at first and after about the 3rd trip when they set it would almost throw u through the window!

[snjparham]

I have integrated GM controller. I had to set at 8 or 8.5 for 8500 lb 5er. I just performed a brake adjustment and I get same braking at 4.5 to 5.

[flc]

Before I traded my 2500HD D/A I was usually at 3.5 and it worked perfectly.

[rockwood06]

My truck is a 2008 Chevy heavy duty 1/2 ton and I have the factory brake system in mine. The Rv dealer set mine at 4.0, I had a 2006 Rock Wood 8314ss. When they set the brake controller the trailer was not loaded to the max and that is 7,910 lbs.

With a setting of 4.0 the truck and the trailer handled great, this set up was the best system I have had in the 11 years we have been camping, the factory installed trailer brake system was money well spent.

May I suggest if you are having problem with adjustment on the truck have the dealer check the adjustment on the trailer first, I had an issues with this with the 8314 when I was towing with a 97 GMC Suburban 3/4 ton, the drivers side of the camper was locking up before the right side had a chance to work.....The camper was two weeks old, they ended up replacing the brakes on the camper and Forest River paid for it......

[hatstomper]

Thanks all. Back to the dealer and have a discussion with the service manager and owner. I don't care if the trim falls off thats an easy fix but if I can't stop the thing we could end up having a garage sale in the ditch some where.

[21C1]

I have an integrated controller in my F150. I run it at 9 with the new trailer and used to run 10 with the trailer I recently sold. I have never been able to lock up the tires on either of the two travel trailers, with any controller. I have a utility trailer that I can lock up when it is empty at a 2 or 3! I usally set the controller so I can just feel the trailer pulling just slightly during a stop. My guess is travel trailer axles and brakes are loaded so close to the max that you couldn't look them up on pavement.

[Coops1]

It is possible they may never lock up, did you warm up the breaks before you did your set up?

I stole the following from another forum where the guy explains quite well how the system works.

If you have it set too high (initial setup), the controller will attempt to lessen the "apply" to the trailer, to prevent trailer "overbraking", during normal stopping, AND, furthermore, when panic braking, the controller, when set too high, will allow initial lock lockup on the trailer, followed immediately by a trailer brake reduction, the moment the trailer changes deceleration. The ITBC will do everything in it's power to prevent the trailer from outstopping or pushing the tow vehicle.

The ITBC, when overset, will sense too much braking action, everytime it applies the trailer brakes, and will constantly strive to dial it back, during that braking event. Once the pedal is released, it will start all over again, So, is the ITBC initial setting correct? I think it's too high, but only you can confirm that, by manually applying the brakes at 20-25mph/32-40km/h.

[hatstomper]

Originally Posted by Coops1

It is possible they may never lock up, did you warm up the breaks before you did your set up?

I stole the following from another forum where the guy explains quite well how the system works.

Intially I had the controller on 4.5, as this was what the other trailer worked well at. I had nothing for trailer brakes. Set it up higher, nothing. Higher, nothing. At 10 you could feel a little braking. Back to the RV dealer. Picked it up Monday, 4.5 very little, manually won't hold the truck at idle. Played around and at 7.5 like they are working but will barely hold the truck at idle. Takes a 10 to hold the truck firmly at idle. I'm going to pull the safety brake cable and see if the trailer locks up. If not back to the shop. IF it does lock up then I guess its the T?????

[21C1]

Pulling the cable will only apply voltage from the TT's battery to the brakes. You said you measured the voltage at the magnets? Is it at least 12 volts? If so, are the brakes adjusted? Are the magnets and drums clean of grease? If so, sounds like the brakes are overloaded. I think larger magnets are available, not sure they are interchangable. Then you are likely going to overload the brake shoe itself.

[hatstomper]

Originally Posted by 21C1

Pulling the cable will only apply voltage from the TT's battery to the brakes. You said you measured the voltage at the magnets? Is it at least 12 volts? If so, are the brakes adjusted? Are the magnets and drums clean of grease? If so, sounds like the brakes are overloaded. I think larger magnets are available, not sure they are interchangable. Then you are likely going to overload the brake shoe itself.

It's been back at the dealer and supposedly the voltage was checked and the brakes adjusted. Pulling the cable while I'm hooked is the test they want me to do to see if the brakes will lock. Just another test I guess.

[hatstomper]

Dealer talked with Forest River and Lippert regarding my brake problem. Dealer decided nothing was working, took off the Lippert brakes. I now have self adjusting Dexter brakes and they work great at a brake controller setting of 4.5.

End of this story....I hope