1999 T2453 Frame Flex

[JohnB]

For Steve Collins:

Originally Posted by Steve Collins

John,

I would not be at all shocked at this point. I put a small bottle jack under the frame by the door, and was able to adjust the thing up and down a lot more than I wanted to see.

The problem is bad enough at this point that the flexing has caused the skin at the top of the doors to fracture. I will probably have to find a small piece of skin to cover that before too much longer. Luckily, it is fairly well protected from the weather by the overhang of the awning.

I am not looking to increase the load capacity of the trailer. That is dictated as much by the axles as the frame anyway, and I would continue to treat the rig as a 5,500# GVWR unit after any fix is applied.

Since I have detected no appreciable flex issues between the rear axle and the rear end of the trailer, I am thinking that I will look into having additional material added from the rear axle forward to the A-frame. That should stiffen the frame sufficiently to relieve this flexing issue in the area where is it problematic.

My only concerns are:

Do I need to use another C-channel of similiar shape and size? Or can I use something smaller and lighter. I pretty much figure that I don't need to double the strength of the frame (or more.)

Can the new material be adequately connected to the existing frame by welding alone, or will I have to drill and install a bunch of bolts as well?

How much weight will the new material add? That could be important.

We have a real good RV repair shop right here (Ballantyne RV). I think I will go have a talk with the service manager and see what they think.

Steve

We are morfing here on this topic so I’m starting a new post for you. For those who do not know how we got here, see this post. TT scissors jack post

First off thanks to Sunline Fan I can look up your 1999 2453 floor plan. WOW your right, that is the opposite layout of the T2499. Amazing.

Looking at the layout, I’m assuming the axles are under the bath room. Can’t see a side pic of your camper to tell. Are they? If so this means the kitchen, fridge, pantry, sink cabinets and forward of the axles. Which can be a heavy part of the trailer. So I can see that the span from the front axles to the tow ball would be carrying a far portion of the TT load.

Where are the fresh, gray and black tanks on this camper?

Now to some of your questions. I’m by no means a TT frame wizard nor claim to be one. But if it was my camper what would I think about doing.

Well first it would be this.

Pull a MIG weld wire, piano wire or just plain string down the length of the bottom of the 4” channel. Make a little sketch of the length, put the axles in and the tow ball. Measure length of each down the length of the camper. And put the tank location in too. Add tanks and any inside heavy items locatins.

Sort of like this. I did this for weight and balance reasons, but you can get the picture of what I’m up to.



Then I would look at the string and see where it dips from being straight as teh wire/string is a straight line. (Pull it tight). And then measure the dip from the straight line and measure a distance from the ball coupler and both front and rear of the axles from the dip location. May end up wiht a few waves/dips. Write them all down. This would tell me somewhat on how the frame is flexing and what loads are above it causing it.

This would help quantify how bad the problem is or is not. Do I have a 1/4" bow, 1" bow, 1 1/4" bow? Pending the amount of bow may help tell you to do nothing or something.

Now what to do with this. Well it depends on how bad the dip is and where. Have to see the data before I knew the fix or if I needed it.

Here are some fix things to think thru if it comes to this.

You asked weight. See this site for structural shapes and weights. Ryerson Steel stock list

A piece of C4 x 5.4 channel that I believe you have weighs 5.4# per foot. Your TT is 24’ 11” long ball to bumper estimating. Estimating your TT tongue to be 46” ball to front of frame where the long frame rails start. This estimate means 299” – 46” = 253” or 21.08’ long frame rails. 21.08 x 5.4#/ft =113.83# per frame rail.

So if you added 2 new long frame rails the whole length out of C4 that is 227.7# added weight. This gets you into the league of say worst case weight gain.

Now, well do I need to add a C4 shape or what? Well here are some things to have to figure out.

First is my frame permanently deflected? If so then when I straighten it, (lift it up) the new adder piece will have to hold the bent part straight as well as carry more new strength load.

Which then leaves us to, well how much strength do I have to add? There are a few way to do this. One is to just measure what force it takes to lift the frame back up to the straight line string.

Do you have a Sherline tongue scale or a force jack? They look like this.


Close up of the gage




Basically you jack up the frame at the max bend areas and read the force, then add some safety to it. AND write down on your sketch where you put the jack in relation to the tow ball and the up force. Now armed with this info you can estimate, do I add 2” channel, 3” channel, need 4” channel, 2 x 2 x ¼” angle iron, 3 x 3 x ¼” angle iron, 3” wide x ¼” flat bar etc and how long it needs to span.

Next is how to get it in there. Well that all depends on how much you need to add. If a piece of 3 x 3 x ¼” angle will fix it or 3” x ¼” flat bar, then you might be able to lay that easily up against the 4” channel you have now. If you have to use a full 4” channel part, you will have to notch some areas and depending cross supports and the notch it might weaken it some but maybe not enough to be a concerns. All depends on the notch depth and where the notch is.

Beams get strength from web width first, then thickness of the web to create some stability and carry enough load, then you need a flange on it to stop it from buckling all up.

I know I have approached this more from a measure and see what you need approach to what a frame shop may say, H’mm OK I’ll just add xx structural shape and be done with it as they have prior experience in doing this.

Welding or bolting. Both will work. Pending what you are mounting, welding may be an issue getting it on the area buy the floor. Bolting just means a lot of drilling. Bolting done right should not be a problem and does not have the issue of burning up areas the bottom of the TT in the process.

Hope this helps point you where to go looking. Really need to know how much frame flex amount, defelection, you have and then figure out if you need to do anything. Armed with this you can even tell the frame shop what you have and if you need to worry about.

John

[kanyonkitty]

Not wanting to hijack this post, but I see where Steve mentioned "stress cracks" in the skin at the corners of the door. I have aluminum siding, and have an approx. 3" crack in the siding on the hinge side of the door. The only way to stop it from getting longer was to drill a hole at the end of the crack, this will keep it from getting any longer and then caulk the crack to keep the elements out. I really had a hard time "drilling" a hole in my new Sunline, but it's really not that big, and it did stop the crack.

Kitty

[Steve Collins]

John,

First, thank you for taking the time to point me in the right direction with this problem.

I don't have the Sherline, so I am going to be winging it in that regard unless I can find one around here.

But, I do have some string and a tape measure, and I will get started on documenting what is going on here. We'll see how that goes, and then see if I need to buy the Sherline to round out the investigation.

The fresh water tank is under the couch in the front end of the trailer. I usually place one of the jack stands under it right where the A-Frame connects to the frame. There is a gusset plate at that connection, and I set the jack stand on the gusset.

Grey water is over the axles, and black is behind that toward the rear of the trailer.

I'll include all of the tanks in the measurements when I do them.

Even before I get started on this, it is now clear to me why Sunline went to the 5" frame, and then to a 6" frame.

Thanks again.

[JohnB]

Steve

While you are out measuring, take some pic's too of the frame setup and any problem areas you come upon. Seeing goes a long ways on these things.

And if you get to the measuring the force to lift it back up there, there are other ways to get an approximation of force to lift.

If you get to this force measuring stage, getting a correction force within say 200# to 300# is real close. Once we know where the bow is or isn't we can dream up ways to get an approxmation of deflection force.

John

[Sunline Fan]

Originally Posted by kanyonkitty

Not wanting to hijack this post, but I see where Steve mentioned "stress cracks" in the skin at the corners of the door. I have aluminum siding, and have an approx. 3" crack in the siding on the hinge side of the door. The only way to stop it from getting longer was to drill a hole at the end of the crack, this will keep it from getting any longer and then caulk the crack to keep the elements out. I really had a hard time "drilling" a hole in my new Sunline, but it's really not that big, and it did stop the crack.

Kitty

Kitty, I'm surprised that you have one of these cracks since your coach is so new. I guess I've just had "good" Sunlines that don't have these cracks. Mine have all unfortunately been aluminum sided. I'll have to look closer when I see mine next.

I'm under the impression these cracks are caused from a lot of road miles, but I may be wrong.

Just so we're all on the same page, here's Steve's floorplan. For those of us who are too lazy to look it up in the brochure :



Jon

[Sun-n-Fun]

Just a thought on a possible solution to frame flexing,

Mount a suitable support under point (C)

Then use cable or a steel rod connected at point (A) and (B)

The support at point (C) should be at the flex/load point,
this way when stress is on point (C) it will apply pressure
downward to the cable or rod that is attached to the frame
at point (A) and (B) and the frame will not flex.

Also when jacking under frame at point (A) or (B) the cable or rod
thats attached will carry the load and prevent the frame from flexing.

Please note I am not a engineer nor professional in any way, I'm only
suggesting a solution that I believe could give you thoughts on solving
your flexing frames. Please consult with a qualified person who can
advise you the correct way to do this.

[Sunline Fan]

I just looked in my collection for a '99 2453 and found one. Here's the pics I have. I know I've had them a while because I had to convert them from Bitmaps to JPEG's to put them on here, and I've been saving the pics as JPEG's for quite a while. So here they are, in case anyone is wondering where something is:







































































Jon

[JohnB]

Jon

Thanks for the pics. Boy when you take pic's, you take pics..... What did you do, rade dealers lot's to get all this stufff?

They will help to this post. I can allready see where the internal components are now in realtion to the axles. Roof vents, side vents, exhaust fans hoods, fill tank holes are all give aways to what is in side in realtion to the axles.


Oh and that is one nice looking camper.

Thanks

John

[Sunline Fan]

Originally Posted by JohnB

Thanks for the pics. Boy when you take pic's, you take pics..... What did you do, rade dealers lot's to get all this stufff?

John,

I can't take credit for the pics. I found those a while ago online. I think a dealer was selling it on eBay, but I'm not sure. I don't have the VIN and the only other info I have on it is that it's a '99 2453.

Believe me, if I were the one photographing that unit, I'd probably have at least 2-3 times more pictures.

Jon

[Steve Collins]

Originally Posted by kanyonkitty

Not wanting to hijack this post, but I see where Steve mentioned "stress cracks" in the skin at the corners of the door. I have aluminum siding, and have an approx. 3" crack in the siding on the hinge side of the door. The only way to stop it from getting longer was to drill a hole at the end of the crack, this will keep it from getting any longer and then caulk the crack to keep the elements out. I really had a hard time "drilling" a hole in my new Sunline, but it's really not that big, and it did stop the crack.

Kitty

I am guessing that your "stress crack" looked something like this:

(Sorry for the lousy pic. I could not get the pic this morning when the sun would have been at my back. It was beyond overhead, and in my eyes when I snapped this a few minutes ago.)

There's one above the latch side of the door frame, too, but it is a bit shorter.

Since they are pretty well protected by the awning, even when rolled up, I am going to deal with the frame first and then contemplate repairs to the two stress cracks.

[Steve Collins]

Originally Posted by JohnB

Jon

Thanks for the pics. Boy when you take pic's, you take pics..... What did you do, rade dealers lot's to get all this stufff?

They will help to this post. I can allready see where the internal components are now in realtion to the axles. Roof vents, side vents, exhaust fans hoods, fill tank holes are all give aways to what is in side in realtion to the axles.


Oh and that is one nice looking camper.

Thanks

John

I'll have dimensions on the placement of the tanks, etc. when I get the measuring done.

Sunline liked the T-2453 so well, they used it almost exclusively in their '99 sales literature to represent the Solaris series.

It has all the interior and exterior features of your T-2499 except for that big picture window on the rear of trailer. Those weren't quite the rage in '99, but came on the market soon after in a big way for many manufacturers.

And, it has the 5500# GVWR frame which is why we're even having this discussion....

[JohnB]

Steve

Seeing this, my 1st thoughts are: WOW...



And Kitty having it too. Even more WOW.

Now it may be more common then I know, but still the WOW factor is there.

Drilling a stop hole in the end of a running crack is standard machinery fix it practices. That will help it stop running.

Right now that crack of yours is a good find and we now know it is on the edge of the door. While you are out measuring, try to get dimensions from crack to TT axle or TT ball coupler. For it to open up there flexing was occurring in some fashion.

And thinking on this, Kitty's crack on the hinge side, and on a 6" I beam frame. Boy on the T2499 there is really not a lot of weight in the TT from the rear door to the end of the TT. Have to think on this one.

And now my curiosity is really up on what my 5" frame flex actually is in measurements.

Curiosity may get the best of me this weekend and I'll have numbers to compare a 7,000# GVWR rated, 5" c channel frame which can be loaded to:

381# 46 gallons fresh
200# added to axles from WD being engaged
950# tongue, no water
5,440# axle loads with no WD.

6,971# Total: With water and with WD engaged.

I normally do not carry fresh water but on occasion at 1 camp ground, I do which takes me to the full limit of the TT.

We can compare notes.

Happy measuring.

John

[Hematite]

Originally Posted by Sunline Fan

Kitty, I'm surprised that you have one of these cracks since your coach is so new. I guess I've just had "good" Sunlines that don't have these cracks. Mine have all unfortunately been aluminum sided. I'll have to look closer when I see mine next.

I'm under the impression these cracks are caused from a lot of road miles, but I may be wrong.

Just so we're all on the same page, here's Steve's floorplan. For those of us who are too lazy to look it up in the brochure :



Jon

Hmm, I'm looking at the specs and I notice a LOT of difference total weight and tongue weight between the 2453 and my 2499. The 2453 dry weight is 3615 and my 2006 2499 dry weight is 5020. Also the tongue weight is 535 vs. 755. Considering it's a reversed design, I'm wondering why the very big increase in weight? Is it possible that the larger frame in the 2006 weighs that much more?

[JohnB]

Hematite

See these 2 layouts side by side.



NOTE: This T2499 is a 2003 model. I could not get one off the sunline site as it no longer exists.



My 2004 T2499 has the 5” channel frame. In 2005 Sunline change the frame to 6” I beam with a 4” channel tongue.

I have measured my T2499 almost every way but loose and I can tell what adds what to tongue weight.

The 2453 loads different and the tongue does not end up so heavy because of it.

The T2499 loads this way.

The DRY tongue weight of a T2499 rolling out of Sunline is around 14.5 to 15% to start with. And goes up from there
Here is my sticker, no walk on roof, alum siding. (Roof and fiberglass adds more weight)


If your 2006 weighs in at 5,020# dry, then there is not much weight change by the 5” channel to 6” I beam.

For T2499 loading: (For relation to tongue and axles.)

Qty 30# propane cylinders, almost all goes to the tongue weight.
The front cargo hole contents: About 64% of what ever weight you put in the cargo hole adds to the tongue. Or 1 # cargo weight = 0.64# tongue
The Fridge adds axle weight - almost no tongue
The pantry adds axle weight - almost no tongue
Everything in the drawers under sink adds axle weight - almost no tongue
Everything in the Living area overhead cabinets, subtracts some from tongue weight
Everything in the Entertainment cabinet, adds most to the axles but does subtract some from the tongue.
Everything in the bath cabinets. Most goes to the axles but a little adds to the tongue.
The rear spare tire on the bumper, subtracts tongue weight.
Everything under the bed, is about a 50/50 split, axles to tongue
Everything in the bedroom closets along side the bed and over head adds about that same 64% to tongue36% to axles.
Filing the 38 gallon fresh tank, adds 115# axles and about 200# to the tongue.
Filling the 6 gallon HWH subtracts from tongue.
The battery, most all goes to the tongue.
The Non Door side peg board cabinet. Most goes to the axles, but some to the tongue.

The 2453, while the layout looks similar and reversed does not load the same in relation to tongue weight. While the both share a mid kitchen, the 2453’s front living area is not as heavy as the T2499 front bedroom and large pass thru cargo hole.

As I have investigated other brands with rear living rooms, similar to the T2499, they too load very similar. A lot goes to the tongue as there is not much aft of the TT axles to unboad it. It comes with that rear living area layout.

Front kitchen layouts also have this similar issues as on those, the kitchen is like 60% to tongue and 40% to axles. The kitchen area is one of the heaviest areas in a TT.

Hope this helps

John

[Steve Collins]

Originally Posted by Hematite

Hmm, I'm looking at the specs and I notice a LOT of difference total weight and tongue weight between the 2453 and my 2499. The 2453 dry weight is 3615 and my 2006 2499 dry weight is 5020. Also the tongue weight is 535 vs. 755. Considering it's a reversed design, I'm wondering why the very big increase in weight? Is it possible that the larger frame in the 2006 weighs that much more?

A couple of things here....

First, the T-2499 is 11" longer than the T-2453. I am not sure where the added space is, but here are the dimensions of the 3 rooms, all taken at waist height: Bedroom 87", Bathroom 37.5", and Kitchen/Livingroom 131". I hooked the tape measue on the base of the windows at both ends.

Tank capacities are all bigger in the T-2499. My T-2453's tanks are only 25 gallons each (fresh, grey, and black.) My water heater is 5 gallons instead of 6. I have a pair of 20 pound LPG tanks instead of 30's.

Obviously, when Sunline morfed the T-2453 into the T-2499, they beefed up everything and made it slightly longer. And, as JohnB states in the next post, the redistribution of the interior affects tongue weight, too.

From my sticker, dry weight is 4399 so the difference between your 2499 and my 2453 is only 621 pounds. Considering the extra 11" of length and the heavier frame, that sounds about right to me.