Tuff chucking issue

Well today he tried pulling with the 7pin unhooked. Still jerked and all 4 brake drum were cool to the touch. The dealer management rode with him, then they hooked up to a larger heavier trailer and still saw the problem. The problem follows the truck and hitch. Although this testing has hilighted a brake issue that needs to be addressed as well. So it is looking more like a truck/hitch issue right now.

We encountered severe "chucking" with our 5er from the very beginning. The push/pull shaking occurred during all aspects of towing. Uphill, downhill, level ground, mattered not. In trying to find a remedy, I researched everything I could find. I decided to install a "5th Airborne Kingpin" That helped dampen the chucking somewhat but it was still very noticeable. Next I installed Firestone Air Bags on the truck. Finally we had a 5er that was pleasant to tow. If I had it to do over, I would install the Air Bags on the truck first. That might have saved me the price of an air ride king pin.
Would like to hear what your friend finds and how he fixed it...

laknox wrote:

RustyJC wrote:
It might also be a situation where the wiring for the forward axle brakes is defective. Definitely needs to be checked out.

Rusty

AFAIK, most trailers have single-loop wiring for the brakes. If =any= wire goes bad, you have NO brakes; just like old-school Christmas lights. Only way to get cool brakes on one axle and hot on the other is if the brakes are not properly adjusted on the cool axle. One caveat, however, would be if each axle were wired independently.

Lyle

Trailer brakes are normally wired in parallel, not series (like a cheap string of Christmas lights). If you have 4 wheels with functioning brakes, each magnet will draw maybe 2.5 amps for 10 amps total. If they were wired in series, all magnets would see the same 2.5 amps.

Most trailer brake wiring is pathetic at best, undersized and running through the axle tubes with no sleeves or grommets where the wires can easily chafe and short. I've seen many where all 4 (or 6, if a triple axle) brakes come to a common junction, others (as I refer to) where each axle's brakes come to a common junction. You wouldn't believe how many I've seen with the trailer brake wiring junctions held together with Scotchloks, and those can loosen and come off - I've found them that way.

I really don't understand the benefit of telling the OP to disregard my suggestion based on your assumption without so much as crawling under the trailer and looking or even checking for brake function with a compass at each wheel. One axle has hot brakes, the other cold. Don't even waste the OP's time checking for functioning brakes?? SMH.

Rusty

RustyJC wrote:
It might also be a situation where the wiring for the forward axle brakes is defective. Definitely needs to be checked out.

Rusty

AFAIK, most trailers have single-loop wiring for the brakes. If =any= wire goes bad, you have NO brakes; just like old-school Christmas lights. Only way to get cool brakes on one axle and hot on the other is if the brakes are not properly adjusted on the cool axle. One caveat, however, would be if each axle were wired independently.

Lyle

goducks10 wrote:

riggsp wrote:
Disconnect the 7 pin connector and carefully drive a short distance to see if the problem goes away, if it doesn't, the problem isn't the RV.

x2

X 3 uphill

riggsp wrote:
Disconnect the 7 pin connector and carefully drive a short distance to see if the problem goes away, if it doesn't, the problem isn't the RV.

x2

Disconnect the 7 pin connector and carefully drive a short distance to see if the problem goes away, if it doesn't, the problem isn't the RV.

It might also be a situation where the wiring for the forward axle brakes is defective. Definitely needs to be checked out.

Rusty

flyfishing48 wrote:
Brake ontrollwe is built in Gain was set to 6
In checking this over we discovered the brake drums on the front trailer axle were a cool 85 degrees. The rear axle brakes would burn your fingers and were over 140 degrees. So either the rear brakes are set tight or the front are loose. Something else to look at.

Your duramax might not be affected by 2 dragging brakes but his gasser is. I'd pull those drums or at least jack them up and make sure they turn freely.

Brake ontrollwe is built in Gain was set to 6
In checking this over we discovered the brake drums on the front trailer axle were a cool 85 degrees. The rear axle brakes would burn your fingers and were over 140 degrees. So either the rear brakes are set tight or the front are loose. Something else to look at.