Trailer brake effectiveness less than expected after adjustment.

[MarkEHansen]

We just inspected and repacked the wheel bearings on our trailer. As part of this job, we cleaned up the brake shoes and magnets (there was some grime, but not really any grease - like from a failed seal). We also cleaned out the brake drums.

We then adjusted the brake shoes according to the manual.

Upon test pulling the trailer, I initially moved my brake controller gain down to 5, but in subsequent test stops, kept increasing the gain all the way back to 10 (this is the max gain on my truck) and still not much "pull" from the trailer when I actuate the trailer brakes using the brake controller manual lever.

It's hard to describe how much "pull" there is, but the braking action is definitely not enough to lock up the trailer wheels. This is when running at around 25mph and applying full deflection on the manual lever.

I would expect that for my trailer, which is pretty light at the moment, and full brake controller gain that we should get the tires to lock up.

Now with our truck we tow with tow mode and the exhaust brake on so the trailer brakes are not used much anyway. I'm really just wondering if I'm adjusting them correctly or if there's a potential problem with them.

Any advice?

Thanks,

[chuckster57]

when we do axle services, we will keep the wheels off the ground, pull the break away pin and then torque the lugs. If the wheel locks up and holds to the specified torque then we let it go, iof not then we adjust a little tighter.

this applies to EXSISTING brake assemblies, NEW BRAKES require a burnishing in period.

[gearhead]

Try it going faster. Find an isolated area and run up to about 45MPH. Don't have your truck in Tow/Haul mode. Try it just normal braking with the controller at 5-7. If it still feels weak, try the manual switch on the dash. I have also bumped my truck into neutral doing this to completely remove the truck from the equation. If it's still weak, eTrailer has complete brake assemblies fairly reasonable.
I think that modern truck computers are outsmarting us. I suspect they speed relate how much brake to apply so you're not slamming to a stop at 25MPH.

[bsmith0404]

Pull your breakaway cable and see if the brakes lock up. If they don’t, there is definitely an adjustment required. The manual lever on your brake controller doesn’t always apply enough to lock the brakes

[skids]

Originally Posted by bsmith0404

Pull your breakaway cable and see if the brakes lock up. If they don’t, there is definitely an adjustment required. The manual lever on your brake controller doesn’t always apply enough to lock the brakes

How do you pull the pin while moving to see if the brakes lock-up?

[chuckster57]

Originally Posted by skids

How do you pull the pin while moving to see if the brakes lock-up?

Pull the pin and then try to drive.

[skids]

Ou sure go for the obvious! Haha.

[chuckster57]

Originally Posted by skids

Ou sure go for the obvious! Haha.

That’s how we do it at the shop, but we use the forklift.

[LHaven]

Originally Posted by MarkEHansen

kept increasing the gain all the way back to 10 (this is the max gain on my truck) and still not much "pull" from the trailer when I actuate the trailer brakes using the brake controller manual lever.

I'm really just wondering if I'm adjusting them correctly or if there's a potential problem with them.

Oh, boy, are you singin' my song.

Took off on a three-hour tour seven-week trip last fall after a full month of being told by my TV dealer's service department and two trailer maintenance shops that there was nothing wrong with either the truck's brake controller or the trailer's brakes, despite the fact that they were behaving exactly as you described.

During the entire trip, we did not "feel" the trailer's brakes cut in even once (now, they could have been actuating really smooth, but I doubt it). We accumulated an impressive amount of black dust on the truck rims. I wouldn't be surprised if the truck's brakes were doing the entire job the whole trip.

I guess we'll find out when I bring the vehicles back to their respective service departments this spring for wheel service.

[sourdough]

Just as a basic check to see if the brakes are actuating you can have someone pull the emergency pin as you listen to each set of wheels, or you can hook it up and have someone hit the brakes....you can hear the magnets activate and pull the brakes from each wheel (at least I've always been able to). If that is working on each wheel then I would check adjustment, put it on the ground, pull the pin and try to move it as Chuck suggested. If they aren't holding then it's time to raise it and take it apart.

When I went to pick up my trailer at the service dept. late last summer I knew the pin had been pulled because I could see the faint imprints of the trailer moving with the tires locked up. Went straight to the pin and yep, pulled, batteries dead, 7 pin connector squashed.... Not a happy camper but got it all fixed like I wanted including new batteries. All to say, check it the easy way before you tear everything apart for a "suspicion".

[travelin texans]

Fairly certain all the newer trucks equipped with brake controllers are proportional, meaning the old way of testing at 20-25 mph & squeezing the manual lever doesn't work anymore, the higher the speed the more brake actuation. As others have stated the best way is pull the breakaway pin, if it moves then something's amiss.
If you have a heavy RV, say 15k+, upgrading to disc brakes is definitely money well spent.

[MarkEHansen]

That's an interesting point, Danny. The truck really over-powers the trailer when towing, so it's hard to tell when the trailer brakes are adding anything to the mix

I'll try pulling the break-away and see what happens.

Thanks to all!

[bbells]

If your vehicle has a built in trailer brake controller that could be your 'problem'. Most of them it is very hard to tell if your trailer brakes are working. You often need to hit your brake hard at low speeds to feel ant effect.

[roadglide]

Originally Posted by MarkEHansen

We just inspected and repacked the wheel bearings on our trailer. As part of this job, we cleaned up the brake shoes and magnets (there was some grime, but not really any grease - like from a failed seal). We also cleaned out the brake drums.

We then adjusted the brake shoes according to the manual.

Upon test pulling the trailer, I initially moved my brake controller gain down to 5, but in subsequent test stops, kept increasing the gain all the way back to 10 (this is the max gain on my truck) and still not much "pull" from the trailer when I actuate the trailer brakes using the brake controller manual lever.

It's hard to describe how much "pull" there is, but the braking action is definitely not enough to lock up the trailer wheels. This is when running at around 25mph and applying full deflection on the manual lever.

I would expect that for my trailer, which is pretty light at the moment, and full brake controller gain that we should get the tires to lock up.

Now with our truck we tow with tow mode and the exhaust brake on so the trailer brakes are not used much anyway. I'm really just wondering if I'm adjusting them correctly or if there's a potential problem with them.

Any advice?

Thanks,

. I distorted a set of brakes at 6 k miles that was covered under warranty last year . The only think I can think of I had the setting at 7 making the trailer do most of the work . I now have my trailer brakes set at 4 and let the Duramax do most of the braking . I row down a hill in neutral press the trailer brakes that stops the rig.

[srvnt]

95% of the time with this symptom your pads are too dirty or your brakes need adjustment. The slide bar on your IBC still bypasses the truck so you should have no problem locking up brakes unless your brakes are a problem. The quality of the trailer industries electric brake assemblies are a joke.

[Whitewolf]

Chuckster57 - Never thought of pulling the pin. What a great tip! Thanks!

[Ken / Claudia]

Same for me, I have been lying on the ground, wheel/tire off ground and spinning the wheel watching and listening for brake drag. Pulling that pin is better and is testing that system too.

[JRTJH]

Originally Posted by Ken / Claudia

Same for me, I have been lying on the ground, wheel/tire off ground and spinning the wheel watching and listening for brake drag. Pulling that pin is better and is testing that system too.

Ken,

This is just my opinion, but I still lie on the ground, spin the wheel, adjust the brakes and make sure they aren't dragging before putting that rubber plug back in the adjustment slot. To me, if you just "pull the pin and see if the brakes drag" (system is working) your brakes may be dragging, and you'd never know it. You could burn up a set of brakes with the dragging and never know what you did. So, jacking each wheel, adjusting until the brakes are tight, then spinning the wheel while releasing the pressure until the shoes don't drag on the hub is still, IMHO, the best way to make sure the brakes are properly adjusted, then, after all are done, pull the pin and see if the entire system is working properly by "visually checking that the wheels lock up on gravel or sandy surface".... It only takes about 4 or 5 feet to do the check, so hopefully a "first timer" won't drag their trailer around the block to test the brakes with the pin pulled.

[chuckster57]

This is how we do it:

Lift trailer and get wheels off the ground

Pull the pin and spin all wheels to verify the brakes are working

Pull wheels/hubs and inspect, service bearings.

Re assemble wheels and adjust brakes.

Pull pin and torque lugs.

Lower trailer back on wheels.

I apologize if it looked like we didn’t lay down on the ground, we do for the adjustment part.

[roadglide]

Chuckster I installed new self adjusting brakes the drums where just turned . I did no adjustments each wheel turned freely. I didn’t like the performance just like the OP of this thread. I checked the shoes all 4 where scored and coming apart . Dexter replaced them under warranty and I broke in the brakes like e trailer recommended. I had my trailer brakes set at 7 not letting the exhaust brakes do it’s full potential and causing the new trailer brakes to work more . I’m set at 4 now and the rig is stoping a lot better dose that make sense?