Ltl- tandem placement in snow conditions.

I would put trailer tandems pretty far forward.
BTW it's often not legal to pull a 53 ft trailer on public roads with tandems slid all the way to the rear. Lots of new drivers have never learned this.

 

Trailer has ABS, so it’ll be a chattery skid, if it does.

I run like you were loaded, all the time, but, even less weight (empty, plastic auto part totes and trays). I leave the tandems slid all the way forward. The weight is already on the nose. Sliding the tandems way back isn’t going to transfer more weight, because there’s very little weight in the rear of the trailer to get out from under; only empty trailer. You can’t transfer weight, if there’s no weight back there to transfer.

 

You are correct that tandems to the rear on a lightly loaded trailer will not be as effective in braking as tandems slid forward. ABS is supposed to prevent brakes locking up, but weight on the tandems improves braking. Sliding tandems to the rear transfers weight onto the drive axles and away from the trailer tandems. You did the right thing.

 

Aim for 60% on the drives and 40% on the trailer tandems.Scale it,Dont get your tandems back too far.

 

Leave the tandems slid up all the way.

25-30k is perfect for snowy conditions if it's spread out evenly. Enough to get you some traction and not push you down the hills too fast

 

The old timer was correct. Besides having better traction on your drives which you might need to make it up a steep road having the tandems slid back means it takes longer to jackknife which gives you more time to respond.

 

The Jack knife that bites isn't the trailer coming around, it's the tractor going sideways, and where the trailer tandems are won't affect the speed of that. Even shortened up, trailer rotation speed is very slow compared to the tractor jackknifing.

OP, just avoid having the trailer heavier than the drives. I prefer have a slight bias towards the drives (couple thousand pounds) as that gives better traction while leaving enough weight on the trailer to keep your braking traction levels decently balanced. It's how we did it pre-ABS because it offered the best balance of traction and stability.