X-chocks: Good, bad or equal? - Page 2

**JohnB** · 11-24-2019, 09:32 AM

I have heard of this happening, the chocks pop out, on the narrower expanding chocks.

The lever type you have, are they about 1 1/2" to 2" wide at the tire face?

mainah · 11-24-2019, 10:29 AM

Only issue I have ever had was self inflicted. I guess it's safe to say they won't stay in if you decided to go for a ride but otherwise they stay put even on a very steep grade.

Tinstaafl · 11-24-2019, 01:32 PM

Quote:

Originally Posted by JohnB

The lever type you have, are they about 1 1/2" to 2" wide at the tire face?

About 2.25". It does make sense that a wider face would be less prone to cocking sideways.

**JohnB** · 11-24-2019, 02:56 PM

To make sure, by your description this seems to the kind you have. Is it?
https://www.amazon.com/OxGord-Chock-...630783&sr=8-31

There are other brands made like that, and other brands not made like that but have the same issue of being able to pop out given the right conditions. The older roto-chocks even popped out easier. I have not seen that type in many years now. It was a single unit between the 2 tires and had an eccentric cam action that moved about a 1/2" to 1" wide cam lobe out into the opposing tire. Even more narrow than the ones above.

While I have not see the exact one I linked, the ones I have seen move out are the narrower ones and are located in the middle of the 2 tires as would be the one above.

I suspect what is happening is, when the camper is forced to move, the rear of the front tire is going up and the front of the rear tire is going down while both tires are rolling forward. The chock in the middle of the 2 tires is seeing opposing forces on the pressure pads against the tires. The large pressure on the narrower chock in that opposing force direction, allows it rotate sort of sideways, the tire can compress and the chock rolls out between the 2 tires.

My wood ones are 3 1/2" wide and the 2 wood blocks are much wider apart. I never did the drag test with them, but came close once during a senior moment. I could tell in the truck something was pulling way too hard when I started out. I stopped, got out and looked.

Duh!

They did not start to roll out, but more like jammed tight on an angle. Being wider, they did not rotate sideways that I could tell by eye, but they were more jammed on an angle no longer parallel to the ground.

Tinstaafl · 11-24-2019, 03:12 PM

That's precisely the set I have, now $10 less than what I paid. Grmph.

Your analysis parallels my thinking. Under the pressure involved when starting a tow, just at one concentrated spot on a tire, it can distort tremendously.

Your wood blocks are monstrous compared to these, as well as having the contact points farther apart. I would definitely expect them to hold much better.

mainah · 11-24-2019, 05:30 PM

Think about what happens when you move two wheels on separate axles with a block in between one pushes up the other one down it's going to come out. Stationary it will stay put.

Tinstaafl · 11-24-2019, 08:13 PM

Well yeah. If nothing moves, nothing moves.

Tinstaafl · 12-08-2019, 02:57 PM

Chocks worked just fine, on a pretty good grade. The pic doesn't show it well, but the tail end was at least 2' up in the air to get it near level.. Confidence restored.

I inched my way a bit farther up the learning curve with this outing. My driveway is fairly steep, dirt/stone. Hunting camp is the same. My son's 4WD F250, though it has plenty of power, was unable to pull the camper up either one from a standing start. It would just spin, even in low range.

Our AWD Chevy Traverse had no trouble at all with either driveway, even with a much less aggressive tread pattern.