What type of couplers do I use for Grade?

[monte1000]

I have buit a few tunnels and trestles.  The cars keep disconnecting from the engine when I go up grade.  What kind of couplers are the best for grade?  Any other suggestions to keep the cars connected would be helpful. Thanks!

[Hunt]

It is not the brand or type of coupler

The usual suspects.

• Couplers are not set to correct height.
• The transition from flat to grade and vice versa is too sharp causing the couplers to lift out.

[Trainman203]

If you run trains of any length and weight up a grade, and have plastic knuckle couplers, sooner or later one of them WILL fail and drop a knuckle. Every club I've ever been to, and every serious model railroader I know, has a no plastic coupler rule on the road.

[Len]

Horn hook work well up a grade and uneven poorly laid track the problem is down grade with them and unrealistic appearance . When they get slack or crash together they release. Was this maybe per design
?

Jon

By the way the uncoupling pin is mounted, horn-hook couplers have a 'shelf', that keeps them from bypassing each other, built into them by default.

'Shelf' type knuckle couplers are available but, as Hunt mentioned, the most likely culprit is the vertical grade transition is too sharp. Which will cause couplers to lift out of each other.

Len