Fifth Wheel Trailer Landing Jack Leg Lubrication

A few years ago one of our Keystone Cougar fifth wheel landing legs completely failed. The leg no longer went up or down and couldn't support any weight.  It ended up being a stripped collar nut in which the worm gear threads. We were on the road at the time, but I was able to order in replacement legs and do the repair myself.

I never figured out exactly why the nut failed, but one theory was a lack of sufficient lubrication. So, to help prevent failures and extend the life of the new landing legs I've decided to make sure they are well lubricated. This summer would be a good time to pull the legs, inspect and re-lube them.

Removing the Fifth Wheel Landing Jacks

Lucky for me removing the landing legs is relatively straightforward on my Cougar fifth wheel. First I have to remove the landing foot hardware and unbolt the inner extension legs spring locking mechanism.

Next, I unbolt the cross member that ties the lead and follow legs together. The lead landing leg is located on the driver side of the trailer and the follow leg on the passenger side. The only difference between the two is a longer shaft on the lead to accommodate the drive motor and gear box.

Then, I needed to remove two larger bolts that hold the landing leg to the fifth wheels inner frame. For the lead leg, an extra step is required. A small plastic collar gets removed and the gear box and drive motor slide off the landing legs drive shaft. Once all the hardware is unbolted, the landing legs simply slide out the top.

Lubing the Fifth Wheel Landing Legs

My primary concern is to get lubrication all over the long worm gear shaft that sits inside the leg. It's like a giant screw. The solution I came up with is to take a 1 1/4 inch piece of plastic irrigation pipe and cut it in half lengthwise. Then coat the inside with bearing grease. The half pipe fits inside the leg and wraps around the worm gear allowing me to coat it well with bearing grease.

Another location that needs attention is at the top of the landing leg where the input drive shaft and beveled gears are located. They are easily accessed by popping of a metal cap. I removed the old grease and pumped in a fresh batch packing it all around the gears and shaft.

To finish the lube job I took a can of silicone spray lubricant and wiped down the inner extension leg and sprayed some into the drive shaft bearings. While things were apart, it was also a good time to clean and lubricate the legs extension lock mechanism.

To test the leg for smooth operation and work the grease in I used my 1/2 cordless drill and ran the leg in and out several times. Before reinstalling, I retreated the legs in as much as they would go, backed them off a slight amount and marked the legs inner portion with a red sharpie. The red line will give me a guideline for max retraction. Many times landing legs are damaged by over retracting.

I reinstalled the legs by reversing my steps and was good to go with a set of smooth operating front landing jacks.

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Connect with Love Your RV!

[riwoof]

And once again, you have to love those people that think that because you live full time in an RV, that every day is a vacation. ;) I hope some of them can catch the last 5 or 6 vids you've made to see what daily chores that are always waiting to be done. Cheers !

[billderinbaja]

I hate to admit it, but my 17 year old 5th wheel has never had any landing gear maintenance. This is the first video I watched, helps alot to understand the parts... thanks!

[TheBuddy]

I know it won't be a breeze keeping the RV maintained and running but, my hat is off to you for making my future hopeful LOL. Great job Ray, keep up the excellent informative videos.

[raymondmills]

I once had a neighbor who had a boat that I would fish on regularly. The cleaning, upkeep and all that went with it convinced me to never buy a boat. You are doing the same for me when it comes to RVs... thanks I think.

[RVMediaCreators]

Great demonstration on how those work. As a RV Tech I’m changing the bevel gears on a landing gear tomorrow. Just brushing up on my landing gears when I saw this.

[pj]

Nice tips and tricks Ray, my landing gear cratered like yours did about three years ago and I decided to go with the Bulldog #500161 dual motor independent leg upgrade and before I installed them I disassembled the legs to inspect the worm shaft and they had very little lubrication on them. The shaft was able to come out of the housing so I could apply a healthy amount of Super Lube synthetic grease. I have to admit, I love having the landing gear legs independent from each other for more accurate leveling and you can wire up the motors for either more torque or speed.

[mielock]

Thanks to your video, I completed this job this morning. I never would've tried this had it not been for your video. It went so smoothly. I used a 1" piece of conduit for the worm gear lube which worked great. Thanks so much for the effort in making this video!

[lucindaherrick]

A much easier way to lubricate landing leg jack screws without wasting nearly 2 tubes of lube: lower the legs about 4 inches, then drill an 1/8" hole 11 inches from the top of the landing leg tube in the center of an accessible side of the tube. Now simply spray lithium chain lube on the jack screw through the hole by using the straw that comes with the chain lube can. It doesn't take a lot of lube to properly lubricate the screw, you certainly don't have to pack the threads full of lube because the nut will scour 99% of the that lube from the screw, causing issues down the road when you try to service the landing leg years from now.

[randycoffey]

This one saved me alot of work I wasn't sure what to do

[garlandstyle]

Love the way you do preventative maintenance. Nicely done Ray.

[cbkb]

Very informative Ray. Love the way you do preventive maintenance just to keep everything in working order.

[psd]

Great job on this video. Very useful since I'm getting ready to service my Keystone Everest landing gear.

[hogcat]

I always wondered how you would grease up the landing gear on a fifth wheel. Good info for sure. THANKS. I see Angie is hanging in there.

[JimCouillard]

My Sabre 5th wheel has Zirc fittings on the leg braces, two on each leg, but they are almost impossible to access and they were painted over! I replaced all four zincs, but wasn't sure how much grease to put in each fitting. Seeing your video showed me that I will have to go back and add quite a dollop of lube grease. Thanks for the heads up and for all your excellent advice.

[billiardobertaev]

Thank you! Now is now every about Rv jack.

[gymsreviews]

I tried this and only time will tell. It seems every year I have a problem with my motors on my landing gear. It is now out of warranty, so when I have to do something I will look and see if you have done it . Keep up with the great videos and cheers. 😎 PS say hi to Angie.

[andyphuong]

Very helpful Ray. I hope your next project will cellphone booster. Thank you.

[anthonymarino]

nice ideas thanks for sharing angie was on break on work

[jerryhuber]

Hi great video and grease is good but for the worm gear and nut I would recommend using anti-seize high pressure lubricant it will make your worm gear and all your other gears last a lot longer than grease, just a thought you might want to check into.

[guzzer]

Nice video. Much much better than the other ones. Not trying to sell me anything, just helping.