China bombs

Rmcgrath53

Well-known member
Merry Christmas all. WE are now in pan handle of Florida nice and warm . We left the cold snow of the Great laqke region and as we were going we stopped and I ckecked the tires. Lo and behold the side walls on each tire had little tumors at least 10 per side. My wife got on the Meggelan and located tire shop allong our route and no won had what we were looking for in stock. Finaly we stoped for gas at an exit that had a Discount tire. All they had was some china bomb carliale brand and a brand from Japan called Landair HT. They were allitle bigger than original but they fit. ( may have to modify the fender alittle but they should work( LT235 85r16). When I was at the dealer they wanted to jack up from the axle. I Told them no way . They didnt have a jack big enough to jack from the frame.So I had a 12 ton jack with me so I offered to jack it in there parking lot. They would not let me do that so they said If I go to the wallmart lot next door and jack it up they would send a couple guys over and get the tires and mount balance and bring back. So that is what happened, they sure gave me alot of grief about not letting them jack from the axle. Any way I hope these tires give me more time and peace of mind. I should say the china bombs were goodyear marathons.
 
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lwmcguir

Well-known member
Curious as to how many folks jack from the Axle? Every camper and every trailer we have or ever had, we jacked from the axle or used the trailer drive on jack which is the same thing. I cant believe the frames are actually that weak, especially the 12".
Just would be interesting to see how many folks have used the axle as the jack location. When you raise the entire frame you are putting more stress in that point than sharing it with the three points via the axle. If someone form Lippert can jump on this I would like to hear an engineering view point from their perspective.
 

driver311

Well-known member
arent the springs hooked to the axles so why cant u jack there.
not jacking on the axles means dont jack in the middle .
not my first flat tire. some people just dont use any common sense!!!!!!!!!!!!!!!

driver311:angel::angel:
 

Rmcgrath53

Well-known member
Both manufacture and lippert say dont jack from axle. If you ythink about it when you jack the one tire up all the weight is on the second wheel. My camper is 12500 lbs loaded. 10000 is about the weight minus the pin . Half of that is 5000 lbs all on one wheel rated at 3400 lbs. Also if you jack at the ubolts you can distort that just alittle and then put your wheels out of alignment.Then you are more likely to get another blowout. JMO.
 

Bob&Patty

Founders of SoCal Chapter
Iwmcguir, it's not the frame, it's the axle's that can be damaged or bent. Not everyone is careful about how they do it. I have jacked mine up a few times. I do lift the coach by the frame and it will lift the front landing gear on that side off the ground. So it appears to me that we are lifting a lot of weight. Also, try to center the jack in the center of the frame. You can bend the lips of the frame if you don't. Dont ask. JMHO Bob:D
 

lwmcguir

Well-known member
Interesting about the axles not taking the static weight long enough to carefully raise the axles high enough to take off and install a wheel. Thanks for the feed back on that. What you said about being careful is in my opinion is well stated and what we are looking at here. I would say that 99% of tire shops out their jack everything of any size by pacing jacks under the axles. (and only under the spring u-bolts as well) I realize the axles are just barely large enough for the load they are carrying on the HL's however the jack should be placed under the spring between the u-bolts, not anywhere else on the axle. Maybe some folks were so stupid they put the jack away from the spring quite a ways and did bend axles. I could see how that could cause an issue and why Lippert may be just trying to protect them selves. I have jacked ours up to balance the tires using the jack under the spring location. Works fine, however we did go with heavier axles right away due to bent hangers from the factory. Still very curious about this as the SOB's we have had prior stated that jacking under the axle at the u-bolts was OK. Could someone from Lippert or Heartland clear this up? Probably not due to liability I would guess. I sure am one that isn't going to jack up the entire coach on one side to change a tire. Talk about stress on a frame, that has to be about as bad as it could get. That is what it entails if you take all the weight off the axles. I guess I am old and cranky as one other poster is as well. On a good note however if you can place a board and jack and lift one side of the coach off the ground from one stress point then the frame sure as heck can stand to be jacked under the axle at the u-bolt location. And as you stated it is about some dummy putting a jack out in the middle of the axle apparently.
 

JohnDar

Prolifically Gabby Member
Somehow, I just think that a 12" steel I-beam is stronger than a hollow steel tube. If it says "jack the frame," that's what I'll do. If it fails, the scuff marks on the bottom, center of the frame will be Exhibit A in the lawsuit. The bent/dented axle tube would be the defense's primary exhibit.
 

lwmcguir

Well-known member
One other quick note about jacking trailers with equalizers. If you jack one axle just enough to raise that tire off the surface, the weight should be shared equally with both axles. This is not the case with Torsion axles however. Again assuming you are jacking under the u-bolt location. This is the way we jack up all of our trailers for the past 50 years or so. I did look at the Lippert Documents and see the statement about jacking under the frame. Has to put way more stress on the coach. Any engineer could attest to that. I guess this is enough about this and time to let it go.
 

Rmcgrath53

Well-known member
I have jacked my rig 2 times at the frame with a bottle jack. It didnt evan creeck . It creeks more when I hook the pin up than it did with the frame. Those who have not lifted up the frame dont know what it does or doesnt do. If the frame is built right, and you jack under the 10 or 12 inches of steel, and lift from there, it isnt a problem
 
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rvn4fun

Well-known member
How many blocks

We carry a 12 and a ten ton bottle jack with us, but after reading this post and the links, I went out and looked with a flashlight and it looks to me that it would be unsafe to be sitting with a flat tire on the shoulder of the road, and then attempt to block up that high to get a bottle jack to work on the frame. Most shoulders angle a little anyway. I used to work in the highway industry and we always jacked under the axel on the spring bracket. After reading the info, I see that it is not the thing to do on the Heartland but how many blocks do you folks carry. Looks to me that this is a accident just waiting to happen.
 

jmgratz

Original Owners Club Member
Just a point of fact. When everyone is talking about jacking on the axle what you are actually saying is jacking on the axle housing which is a hollow tube that the axle fits in. The problem with jacking on the the axle tube is it can bend the tube and ultimately bend the axle. If you need further clarification on this call Lippert and talk to the experts there. BTW just because the high school kids working at Discount Tire do that all the time does not mean it is the correct way. Have a great New Year.
 

Rmcgrath53

Well-known member
I posted my experience to help others in the same boat. If you have decided to do it the way you have been doing for x years, right or wrong then that is your choise. I did by the recomended way with no problem. I was on an incline in the wall mart parking lot and didnt have a problem. I think it took about 5 or 6 2x6 and the jack. I would not want to do it on the side of a highway without a nother jack for safety. But there again that is why I decided to scrap the china bombs when they started showing signs of a potential blowout so
I would not have to change on the side of the x way. have a great new year.
Ron
 

caissiel

Senior Member
I do all my work on my RV and the only time I ever jacked the frame of a 5th wheel, I used a jack between the 2 axles, and that was when I worked on the axles off the trailer. I see a lot of tire shops that realy don't care where they put the jack and sometimes they are way in on the axle with their floor jack. On my truck I saw one service man jack it by the Center. I just tell them not to. I Just refuse to have them do it from the center. On trailers it sure would bend the axles if they not jack on the spring centerline. The center web of the beam is no thicker then the 1/4" tubing of the 7000LBS Axles.
 

lwmcguir

Well-known member
Jacking the frame of a heavy Fifth wheel to the point the tires are off the ground is dangerous by any means of the imagination. That is why almost every tire shop is going to look at you like you are crazy. Puts a lot of torque on the frame as well. If you are worried about bending the axle then the axle is to light and you better upgrade it. Put a block of weed between the jack and the axle or use a jack that has a large pressure point that covers both the spring u-bolts. That is the best way in my opinion. I am never going to jack my camper up with the tires off the ground with only one jack. That is just plain crazy. As noted in the other post look how thin the light weight I beams are. Get over to the side a bit and you will bend it and slip off and maybe put your jack up through the coach floor. That should be interesting to see.
 

porthole

Retired
Before you go through all the trouble of jacking a tire off the ground - have you tried rolling one tire up a ramp and eliminate the jack issue altogether?

That is easy enough to test the next time you move the trailer. If it works for your configuration go and buy one of those "ride on jacks". Not the one you roll the axle onto, rather the one you run the good tire up on.


The wheel rated at 3400 pounds holding up 5000 pounds is not an issue, you are stopped and have no dynamic loads on the wheel.
Besides, if you have a flat you already have a dynamic load on the good wheel while trying to get off the road.

My trailer sat on frame jacks for 30 hours at Mor/Ryde with no problem.

I see no reason why you can't jack on the frame. The problem is the distance from the ground to the frame.

Personally, I would use a 12 ton bottle jack, and a low profile one at that. and block it up to get as close to the frame as you can before extending the piston.


BLOCKING THE JACK
This is the critical part. Use multiple pieces of wood and criss cross the pieces as you go up. See the attached PDF for an example.
We have picked up tens of thousands of pounds this way.

You don't have to get as fancy as the PDF shows, we tend to overdo everything :D

For us, I would think 2x6 boards about 12" long would work fine. You probably already have some of your cribbing in your landing gear blocks bin.
A block of wood between the jack pad and the frame too. Unless you have a friend make you up a "jack" cradle (U-shaped piece of steel to cradle the frame with a piece of pipe welded to the center).

You all would be best off, if you have the inclination to do this, to try it on a level area when you are having a "good" day.

Do it once having a cup a coffee and you will be able to do it when you "have" to change a tire.

Either way I wouldn't change a left side tire on the highway, unless my brothers in the big red trucks were "lane blocking" for me.
 

Attachments

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caissiel

Senior Member
Well said, I totally agree. When I jack I always back it up with blocking, but the jack holds the load.
 

lwmcguir

Well-known member
We use the trailer jacks on all our trailers including the Landmark. They just make a lot more sense than twisting a trailer frame and having an entire fifth wheel off the ground on one side. However that isn't acceptable per the warranty. I think you make some really good points about the cribbing. We have a lot of wind and I just don't like the idea of my camper up on a single bottle jack touching a tiny little I beam. It could easily slip off with any movement so the TV and all the other tires need to be chocked as well. We will continue to jack the axles or use the trailer tire jack. Have one in each TV and really think that is the safe way to do it. You guys that are going to raise the trailer should have some kind of adapter made to go between you jack and the I beam in my opinion. Hopefully with the better tires and springs this wont be much of an issue going forward. Just curious, how many of you have gone to a tire shop that is willing to jack up the frame to change a tire?
 
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