Trailer Tires Locking Up During Turn?

The other day I came to a T junction and was making a left hand turn. Cross-traffic has the right of way and doesn't stop. After coming to a complete stop and waiting for traffic to clear I initiated the left hand turn. I usually accelerate to about 10 mph to make a turn, which I did this time as well, but as I was entering the intersection I spotted another semi coming from the right around a blind curve in the road (visibility of about 1500 feet or so). As I was already halfway through the turn and into the intersection then I was fully committed, so I started to accelerate further than what I normally do - probably up to 15 mph or so - when all of a sudden my trailer tires lock up (or at least the driver side), start smoking and rubber is starting to be laid on the road. I hit my hazards to let the other driver know there's a problem (as if he can't see it already) and start applying the brakes, which oddly enough releases the tires from being locked up.

It's as if the trailer had a mind of its own and thought that I was making the turn too fast or something and decided to lock up until it got back down to a more reasonable speed.

Has anyone else experienced that? And what would cause this? It definitely was a potentially serious hazardous situation. One that I would love to avoid in the future.

How long had you been driving at speed prior to the intersection slow down, stop, and getting back up to speed?

How long had you been pulling this particular trailer?

Was it loaded or empty?

My guess is that when you applied the brakes at the stop sign, the brake shoes failed to release. To me, this would indicate a defect in the brake chambers or something related to the air brake release mechanism. That is probably just stating the obvious, (since I’m not a mechanic) but I would be looking to get that trailer into a shop and written up for bad behavior.

Maybe Stevo would have better insight into what caused this.

BK you may be right, on your comment. Only thing that I can think of causing this to happen. Or it was serviced recently (trailer) and they over tightened the brakes. Or the S-Cam actuator, is dry/not lubed and just happened to stick?? Or the dang S cam's actuating part is worn/grooved, bound up somehow hmmm.

Could've just been a freaky 1 off thing that happened?

In my diesel wrenching days, seen a LOT of messed up S-cams, bad bushings in their housing tubes etc. 1 time working at a tanker outfit in L.A. I had to cut off the S-cam housing braces on the axle tubes,& replace the whole things, and re-weld the new braces on both rear axles (that was hella fun, cutting & welding while wedged between both axles lol)

The slack adjusters were like 18+ inches away from the drums, long tubes

How long had you been driving at speed prior to the intersection slow down, stop, and getting back up to speed?

How long had you been pulling this particular trailer?

Was it loaded or empty?

I had been driving for about an hour. I had just picked up a D&H load from Schreiber in Richland Center, WI, and I was southbound on the US-61 truck bypass near Lancaster, WI, turning left onto US-61 S.

I was stopped for 2-3 minutes waiting for traffic to clear before making the turn. Got up to my typical 10 mph to make the turn when I saw the truck coming from the North around the curve so I started to accelerate through the turn to clear the intersection. It locked up after I started to accelerate beyond the 10 mph, though I don't know exactly at what speed because I was focused on my mirrors and what the truck and my trailer were doing.

This is actually the second time something like this has happened to me.

The first event happened probably about a year ago. In that instance I was also loaded, had been driving for 2-3 hours at freeway speeds, westbound on I-80. I pulled off the freeway at Sydney, Nebraska, heading to Love's to take a 30. Stopped at the stop sign, just long enough to come to a complete stop and verify it was clear, before making the left turn.

In this instance I wasn't in a rush and was making the usual 10-12 mph turn before the trailer brakes kicked in about halfway through the turn. But it didn't full-on lock up as the most recent experience did, it just noticeably slowed me down a couple seconds until completing the turn.

In both cases I called maintenance, described the experience, and asked what was going on but they had no clue.

I'm just as clueless and my only guess is maybe there's some kind of safety 'feature' in the truck or trailer going off. Much like the collision avoidance system that'll go off if it sees the shadow of an overpass or road construction materials in a construction zone while going through a curve and it thinks you're about to collide and so it automatically starts screaming at you while applying the brakes, much to your chagrin. Whatever the case, it seems to think you're going to fast through a turn and kicks in the trailer brakes to slow you down.

In a maybe slightly related vein, I've noticed on occasion when at speed on highways and freeways, when going through a curve (even gentle ones), sometimes the trailer seems to try to slow down of its own accord. It's hard to describe, but I can feel it stutter or lurch for a split second, like it doesn't want to be going at that speed in a curve. I could even be going well below the posted speed limit, or what I feel is a safe speed for the curve, when I 'feel' it happening. It's a very subtle feeling, but I can feel it nonetheless - like something is tapping on the brakes for a fraction of a second. I haven't ever reported or asked about this since I'm not even sure how to describe it or what I'd even be asking about. It's just... strange.

Ondag, your experience really hit home with me, almost literally. My sister lives between Fennimore WI and Lancaster Wi. You drove right by the farm she lives on off Circle Rd. The intersection of which you speak is very familiar to me and I just recently drove the same route. (You can always tell when there is a funeral procession on that highway because the lead Farmall tractor has its headlights on as do all the others.)

I think your wheels locked up because you were in the negative energy field generated by my sister. On behalf of my family, I apologize and recommend that you find a detour around that area in the future.

My two guesses for the cause are 1) There was an air pocket in the brake system, or 2) There was a problem with the air proportioning valve on the trailer. It was not a safety sensor on the tractor.