HappiJac 4500

Disregard. HJ offered me a factory second for a decent price.

I’m glad they worked it out for you. Bummer that it failed though.

I think you got lucky.

I have a heavy camper and the 4500s aren't heavy duty enough for it. I have wanted to replace 2 bent 4500s for years but couldn't make myself pay the price as the old jacks still worked with the manual crank.(blew fuse if I used the motors) I never found them at a discount.

I did find a set of 4 Rieco-Titans replacement jacks for slightly less than the price of 2 4800s. I also found that I could buy a set of Rieco-Titans with motors and brackets several hundred dollars less than the Happijacs. But the cost of a complete system still kept me from buying. (I,m frugal)(haven't justified it yet anyway)

I then learned that I could straighten them. And after straightening the worst one they now work with electricity again. So I will keep using them until I can't fix them, and then I'll see if I can make myself spend the money for a set of the Rieco_Titan 2500s.

I'm getting a factory second 4220 for $372. I think full MSRP is about $450. Supposed to fit my current motor/gearbox.
In all honesty I believe the failure was my fault. My camper has been sitting unused for a year. It's always covered with a Classic Accessories cover that keeps most of the rain off. I put small plastic buckets over the front motors. But the jacks haven't been exercised in that years time. The inner tubes corroded to the outer tube. I beat on the foot of the inner jack with a sledge hammer so much that I cracked the weld on the foot. But it came out, maybe 1/8" inch at a time at first, then more later. That's after a couple days of soaking with Kano Kroil and WD40 rust penetrant. The acme screw was in good shape. I lubed it with marine grease and Nuclear Grade Nickel Never Seize. I just put it back on the camper and it seems to be good to go.
The other front jack came apart a little better. However the acme screw is locked up inside the bottom assembly that is not serviceable due to it being crimped in place. Pipe wrench with a cheater pipe and hammer was no help. That is the one I am replacing.
I think it would be wise to talk to Customer Service at HappiJac and order some spare parts for the future. Particularly the parts that are unique to the non-current jacks, which is likely most of them. I would recommend at least the disengagement assembly, including the lever and the small delicate tab opposite it, the thrust bearing, and the O ring.

I had the same thing happen 2 years ago when I was about to load the camper for a long trip. I ordered a replacement from Tweety's. The correct replacement was a Happijak 4800. It seems identical except slightly longer to compensate for the higher sides on many new pickup trucks. The cost was $313 including tax/shipping. They shipped the day I ordered and it came on the second day after I ordered. I have had several good experiences with Tweety's and suggest you give them a try next time. Sometimes there is no price difference but they seem to be very technically knowledgeable and orders are shipped and received very quickly.

I have done business with Tweety's before. I looked on their site but didn't see anything. It may be there though. I could have used a wrong search term. I will say Tweety's isn't my usual first choice. I live in Texas and have to pay sales tax on Tweety's purchases.
I thought I was going on a long trip in a couple weeks, thus prepping the camper. But the dirt track races in Charlotte will be there next year. My credit card is smoking from the jack issue and the 5th wheel in the shop after a tire blowout.
edit add: I just looked again and yes Tweety's has the 4220 jack. $450.

Just checked Tweetys, $427 for the 4820's that I got (2) for $373 ea. from RVPARTSPRO (ebay) + free shipping.

4820 - 2800 lbs. Cap.
4220 - 2200 lbs. Cap.

Yeah I don't think Tweety's is cutting anyone any great deals.
I probably should have gotten a better idea on what was compatible with what I have. The extra capacity would be nice, but hopefully not needed.
I think when I searched Tweety's I was looking for 4500's; replacement in kind. Dang that sounds like work. At least I won't have to fill out a "Make Change" document and go before the joint Maintenance/Operations committee. LOL

Perhaps the 4800 I bought is no longer available. I do agree it can be hard to find items online with Tweety's. I have called them several times and always received an immediate expert opinion. Prices on many items seem to be fixed by the manufacturer. That could be the case with Lippert. That happened when I bought Timbrens and also Torqlift tiedowns from them. They were able to give me information on the correct part numbers and also shipped immediately so I had the items within a couple of days. There could be equivalent or better choices than Tweety's. I do know they are much, much better than the big guy.

The 4500 front jacks on our Bigfoot started binding terribly about 3 years ago. We replaced them with 4800 jacks. They are 3” longer, run slower and have more weight capacity than the 4500’s. Made a huge difference loading/unloading. More stable and secure. Tha 4800’s are still in production. We have had zero problems with the rear jacks/motors