Trailer unable to unhitch on steep hill

Have you tried chocking the wheels on the trailer and nudging the car a fraction to take the strain off?

If the ball really doesn't want to release because of neck binding on coupling, undo the ball nut and remove the ball from the towbar. Obviously, you have to have no pressure on either to release. OR run the rear wheels of vehicle up on a ramp/timber or similar to raise the rear as you get to position . That lessens the coupling angle.

Use screw jack to raise A frame and take pressure ball pressure off the vehicle.

Make a lanyard/chain to secure boat trailer to property, ie, D bolted to driveway at suitable point, when in position and it is held there. Jiggle vehicle to release ball coupling.
OR
Buy a small 12v winch or hand winch and drag the boat from the road, then it can hang on the cable when not used.
Plenty of options.

Agree with RMD. I think the best solution here is to get a cheapo winch and put that in your garage. It'll come in useful for other things too.

Or, you could hook it up to the back of your boat trailer, so long as it's a sealed/ waterproof one. Possibly just a mechanical one you can douse with grease.

Rather than stuff around with winches why not change to an off road type fully articulated hitch. Ball couplings can be a pain even with small angular misalignments.

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I think some responders have the wrong understanding of Matt's problem. He says.... "My car is on the steep decline whilst the boat trailer is on the flat in the garage."
It is not that the boat is pushing down on the car. So a tether or winch is not of use.
The problem is that the angular relationship of the coupling prevents disengagement and some have realised that by recommending replacement with a different coupling style.

Chock the wheels of the trailer very well. Then use the jockey wheel to raise the hitch 60 - 70 mm. With the hitch up and the trailer secured, put your foot hard on the brakes and slip the tug out of gear. Then just slacken the brakes a little to let the tug go forward a little. As you do that the ball should slip out of the coupling. On the other hand, if the tug is pulling against the coupling, reversing the tug towards the trailer frees the ball from the coupling.

I use this trick frequently when my tug is on a slope and the ball is pulling or pushing against the coupling. It only takes a few millimetres of movement to unlock the coupling from the tug.

Have you thought of putting a pulley further up the garage area, uncouple the trailer on the flat and then tie the trailer with the rope, pass the rope over the pulley and use your car as a winch to drag the boat up backwards? The pulley will control the direction of movement of the trailer. This will work OK to uncouple the rig, as well as coupling it up again.

Hi Matt,

Given all the previous responses, I would suggest a Poly Block coupling such as a “Tregg” coupling might be more suitable. The McHitch Auto Coupling is a good bit of kit, (I have one on my 2.7 Tonne Off Road Van), but can be difficult to connect/disconnect if the approach and departure angles are too great. I used to have a Tregg Coupling on my Kimberley Kamper, and the same on my Goldstream RV wind up off road van, but opted for the McHitch Auto Coupler for my current van. I do not have the same problem that you have with the extreme angle for connect/disconnect, so it suits me fine.

Macca.

X2 against the Tregg for this situation
I've had two CT including a KK with Tregg hitches. If the boat and trailer weigh more than 1T, there is no way you will pull the pin out if there is any lateral strain on the hitch
That's about the only downside I found with Tregg hitches.
On a slope you have to arrange the trailer and vehicle such that there's almost no strain on the tow assembly. That's easily done on a level surface, but not a slope. Our Hybrid van has a DO35 hitch which is much easier to work with when the vehicle and trailer are on a slope.

Hi Matt,
We have exactly your situation where our van is parked on the flat but the tug is on a sloped driveway after reversing the van into its parking spot. We have a McHitch and it works perfectly - dead easy when unhitching or hitching. I have a circle marked on the moving bit of the jockey wheel and just wind the jockey to this position. As long as the hitch is in compression (ie the weight of the vehicle is NOT pulling on the hitch, its just a matter of removing the main pin, lifting the handle and then driving away. Hitching back up is simple providing the nose of the McHitch is angled downwards to match the angle of the receiver on the car. I just reverse using the camera on the tailgate and 99 times out of 100 the McHitch just locks in and we're done. Just occasionally, it requires a small juggle up or down on the jockey wheel, usually because I've unhitched with an empty fuel tank and am re-hitching with a full tank in anticipation of a decent road trip ahead. We love the McHitch because it's also dead silent. If your boat trailer is less than 2 tonnes or you also have a box trailer, I have an almost brand new 2T McHitch trailer coupling in the garage for sale at half price if you want to save some money. If your boat and trailer is more than this, you'll need a 3.5T trailer hitch. The car side of the McHitch is the same in both cases. Hope that helps. Keir

I use one of the Alko off road ball joint hitches so that I can tow my box trailer as well without stuffing around changing the tow ball out. It would probably help you unhitch.

https://alko.com.au/product/solutions/couplings/off-road-ball-coupling/