Pull test with hydraulic jacks?

[Ed & Cathy K]

We just watched Enjoy the Journey's latest video. They thought the 5th wheel hitch was locked.............It wasn't. When they retracted the front jacks, one went up before the other. How do you do a pull test with hydraulic jacks. I have a Reflection with electric jacks and they retract even. I can raise them a inch off the ground and do my pull test.

[Bigjaike]

We just watched Enjoy the Journey's latest video. They thought the 5th wheel hitch was locked.............It wasn't. When they retracted the front jacks, one went up before the other. How do you do a pull test with hydraulic jacks. I have a Reflection with electric jacks and they retract even. I can raise them a inch off the ground and do my pull test.

When I retract my front legs I will stand in the curb side and put my foot on it until they are about 2 to 3 inch off the ground (curb side always comes up first on mine) and then I will do my pull test,

Monty

[colan]

The process I follow for pull test with hydraulic jacks:

1. Retract All
2. In manual mode extend the front jacks, starboard (right, curb side) side jack extends first.
3. Continue extending until the port side jack is about two inches from the ground.
4. Push the retract, button, retract front. Just as the starboard side was the first to extend it will be the first to retract. Retract about two inches.
5. Perform the pull test.
6. Retract all.

[JBill9694]

It is interesting that everyone seems to want to trust their hitch before doing the pull (bump) test on the hitch while our owners manual indicates that the landing jacks are retracted after the test, see copied portion below. The purpose of the bump test is to make sure that the hitch is properly closed and latched about the pin. If it isn't there is a risk of the tow vehicle sliding out from under the hitch and if the the landing jacks are raised off the ground the trailer can drop. Our vertical hitch weight is 3,860 pounds, dropping this weight just 2" subjects the landing jacks and connecting bolts to a force of 20,700+ pounds. That's a lot of stress to put on those items.

I encourage all of you to revisit your owners manual(s) and to follow the guidance provided for performing the bump test. Our Ram owner's manual has a better detailed procedure that talks about applying the trailer brakes before doing the bump test.

Sorry if this sounds preachy.

5. Back up your truck so the hitch encircles the FW pin.
6. Making gentle contact of the hitch saddle against the pin
will cause the mechanism to close.
7. Secure the hitch lever as specified in the manufacturer.
◦◦ Shift the truck into drive, but
◦◦ DO NOT press on the accelerator.
◦◦ Bump the hitch to make sure it is locked.
8. Check that the FW landing legs are fully RETRACTED.
9. Attach the breakaway switch cable to the tow vehicle.
Leave enough slack to accommodate tight turns.
10. Connect the 7-way wire harness from the FW to your
tow vehicle and secure in the travel position.

[OffToHavasu]

It is interesting that everyone seems to want to trust their hitch before doing the pull (bump) test on the hitch while our owners manual indicates that the landing jacks are retracted after the test, see copied portion below. The purpose of the bump test is to make sure that the hitch is properly closed and latched about the pin. If it isn't there is a risk of the tow vehicle sliding out from under the hitch and if the the landing jacks are raised off the ground the trailer can drop. Our vertical hitch weight is 3,860 pounds, dropping this weight just 2" subjects the landing jacks and connecting bolts to a force of 20,700+ pounds. That's a lot of stress to put on those items.

I encourage all of you to revisit your owners manual(s) and to follow the guidance provided for performing the bump test. Our Ram owner's manual has a better detailed procedure that talks about applying the trailer brakes before doing the bump test.

Sorry if this sounds preachy.

5. Back up your truck so the hitch encircles the FW pin.
6. Making gentle contact of the hitch saddle against the pin
will cause the mechanism to close.
7. Secure the hitch lever as specified in the manufacturer.
◦◦ Shift the truck into drive, but
◦◦ DO NOT press on the accelerator.
◦◦ Bump the hitch to make sure it is locked.
8. Check that the FW landing legs are fully RETRACTED.
9. Attach the breakaway switch cable to the tow vehicle.
Leave enough slack to accommodate tight turns.
10. Connect the 7-way wire harness from the FW to your
tow vehicle and secure in the travel position.

Yes, but no as well. There are some caveats or additional information to what they provided:

I'd want to make sure the landing gear is raised up a bit after connecting to the truck. If there is movement, there is the potential to tweak the landing gear if binds on the ground. Then you're stuck with stuck landing gear. Even when driving semis, we always raised the landing gear a tad to prevent this. The once shock wouldn't do anything if 5th wheel was not engaged.

[JBill9694]

This is really about risk reduction and comfort level. Playing my own devil's advocate I will note that the bump test is actually the third check on the hitch; first is a visual inspection to make sure the jaws are closed around the pin and second is making sure the lock bar is in place and pinned; so an argument could be made that there is little chance of the truck moving out from under the hitch and dropping the trailer during the bump test.

On the other side of the coin, chocking the tires and applying the trailer brakes during the bump test will help reduce the risk of side loading the landing gear jacks. Also, the pulling force exerted on the pin during the bump test is fairly nominal. Remember that all your really doing is letting the truck roll forward into the pin. If you're big and burly enough you could do this with the truck in neutral and just push it to make sure the jaws of the hitch are properly engaged.

With any risk analyses consequences have to be weighed. If the bump test is unsuccessful with the landing jacks down there will likely be no damage to the truck or trailer. If the jacks are up there could be damage to the jacks, to the truck's bed side panels, and/or to the trailer itself. Any of which could leave you SOL.

If there is damage to one or both landing jacks due to side loading during a successful bump test then you may have to pull out the tools and remove the damaged jack(s) but at least you'll be hitched up and able to take the trailer some place for repairs.

Each of us need to weigh the risk and consequences and proceed in the manner that we are most comfortable with. Whether that is to doing the bump test with jacks up or down, I wish each of you safe travels.

[Randall Lee]

I've only been a 5th wheeler for a little overe a year. I have always followed JBill's idea; visual, locking pin, truck in gear trailer breaks. If nothing moves without putting on the gas I happy.