View Full Version : Outfitting questions on jack/power

09-12-2005, 03:12 PM
Just ordered a new 3124KB. Thanks to all on this forum for helping us make the right choice. We undoubtedly would have made a mistake without your comments and advice.

Now we have a couple of questions on equipment; One, what size/type of jack are most people carrying? (I'm referring to jack for changing a flat.) I assume a bottle jack would be preferred, but how short a jack do I need to get under a flat wheel--assuming a 2X6 underneath to steady it--and how long a throw do I need to get the wheel high enough to mount the spare? Has anyone tried a rolling floor-type hydraulic jack instead? How did it work?

Secondly, the 2006 brochure shows a "45 amp" power converter vs. the former 30 amp. Does this mean I can use 45 amps of AC power, coming from the 12 volt battery? Or is it just to take a spike? This sounds like a big draw from a small battery. Obviously, I'm missing something. Just want to know what.

Thanks again for a great forum. Am subscribing permanently as soon as I get an address and can get a check in the mail.

Jon and Rita

09-12-2005, 03:32 PM
Jon & Rita

I'll answer the "45 amp" question. That is the rating on the 12V maximum output. I believe this is a steady state rating, so you should be able to draw a total load of 45A from the converter when plugged into shore power.

Your main battery fuse is 30A, so that is the max current either charging or discharging of the TM battery.

Thats a good question on the jack. One has to get under the frame with flat tire & raise it sufficiently to get the new tire on. That's more extension than small "Checkers Auto-type" bottle jacks have according to what I have found. The roll-around floor jack would be great but its pretty big to be hauling around. I have the 2-axle 3326 and hope to back the good tire onto leveling blocks to change a flat. In an emergency, the leveling jacks can be used on the newer TM models.

Welcome aboard!

09-13-2005, 06:55 AM
Jon & Rita -

When we had a flat last year, we ran into the jack problem you describe. With a flat tire, the frame ends up pretty close to the ground, so you need a short jack to get under it initially. But as you observed, a short jack doesn't have much throw, and my jack's 6" or so of lift wasn't enough.

THE HARD WAY: When my bottle jack reached the top of its extension, I put some blocks under the frame, lowered the jack, put some more blocks under the jack base, and pumped the jack up again. Two lifts was (barely) enough to do the job. Good thing - I didn't have enough blocks to go for a third lift.

EASIER: Instead of putting blocks under the frame, I think it would have been faster and easier to simply lower the stabilizers at the end of the first lift. Then remove the jack, block up its base, and go for the second lift.

BTW, it is probably important to remember the instructions (in the owner's manual) to place the jack under the main fore-and-aft frame rail - not under one of the side wing rails, and not under the axle.


09-13-2005, 08:53 AM
Jon & Rita,

I carry a small hand crank scissors jack in the TV. I bought it to stabilize my '97 2720 under the entrance door. The frame on the '97 did not seem to be as strong and resistant to twisting as the newer TM's with the installed scissors lifts. A scissors jack will fit under the frame even with a flat tire and will lift the tire off the ground for changing. I don't have to worry about hydraulic fluid with this type of jack and it is very compact and light weight to carry. You can also find a scissors jack that has a hydraulic cylinder to raise the jack. You get the height range of a scissors jack with the pump action of a bottle jack. Of course it is heavier, bulkier and costs more than the simple hand crank scissors jack.


09-13-2005, 11:06 AM
Thanks for the replies. I think I've got it now. Wasn't sure whether we were talking converting battery DC to AC or shore power AC to DC. (yeah, I know; AC to DC is really "inverting" rather than "converting," but I see these used interchangeably a lot.) Sounds like they are giving the 2006 model a little more DC when on shore power to handle more DC lighting, fans, etc.

We're new to RVing, so still learning different ways to run equipment . Since we don't yet have the TM or its manual, I'm probably getting a little ahead of the program, but want to have all the needed equipment before we test the TM overnight at the dealer's place. My real (unwritten) question was whether the standard equipment 25A extension cord would be sufficient. I am assuming it is; you're just taking 120V/25Amp max AC from shore power and converting it to 12VDC, and you can use up to 45 amps of DC from it. So I don't need a 50 amp rated extension cord and 50 amp shore power connection, correct?

Incidentally, I am trying to subscribe to the forum by check, but am having no luck with getting an address to send the check. (The website auto-answer feature is not working, at least with my computer setup.) Can anyone supply the correct address? Thanks again. This is a great group and I, for one, really appreciate the patience and generosity of you veterans giving easily understood answers to some of us newbies with our naive questions.

Jon and Rita

09-13-2005, 11:53 AM
Incidentally, I am trying to subscribe to the forum by check, but am having no luck with getting an address to send the check. (The website auto-answer feature is not working, at least with my computer setup.) Can anyone supply the correct address? Thanks again.
You can try the link that Chris gave me:
[email protected]

His snail mail address is

1759 Mesa Grande Loop
Rio Rancho, NM 87124

When we had a blowout on our 3124KS a few years ago, I used a bottle jack to raise the axle to the limit of the jack's cylinder. I lowered the scissors stabilizers to hold it at that height and then put blocks under the bottle jack to raise the axle even more. It took a couple of sequences of doing this to get the damaged tire high enough off the ground so that it could be removed. I carry a 6 ton bottle jack in our truck.

I like Mike's suggestion of using a combination bottle-scissors jack under the TM's axle, but, can't visualize how this device could be low enough to get under the axle with a flattened tire. Mike, do you have any links that will show what this device looks like?

09-13-2005, 03:32 PM
Please don't put the jack under the TM's axle. It could dent the axle tube. If the tube is dented, it is liable to progress to a crack and failure from fatigue.

This bottle-scissors jack is availiable at JCWhitney:
I have seen them at the local Wally World.

09-13-2005, 05:43 PM
So am I to understand that you cannot use the TV's jack on the TM?

09-13-2005, 06:51 PM
No. You can use any jack on the TM. But whatever jack you use on the TM, must be placed under the TM frame. It must NOT be placed under the TM axle. Please check your owner's manual.


09-13-2005, 07:15 PM
Got it!

Harry Womack
10-05-2005, 04:11 PM
I use this jack I got from Sam's Wholesale. It rolls under the trailer and has a range from 6-1/8" to 15". It has a two stage hydraulic bottle jack. I have not seen them at Sam's for a while. The name on the jack is Shinn Fu Co. Kansas City. Model Pro Lift 4400. This jack is only about 10" long.

10-06-2005, 08:13 PM
As you all probably know a scissors jack will slide into a space approximately 4 or so inches high and lift hgiher than a bottle jack. There are also different size scissor jacks that will slide under the same space. The only difference is the length when collapsed. Also the scissors jack is lighter than a bottle jack. My 2 cents worth.