Cracked web in Frame

First topic message reminder :

When I pulled the tire with the tumor off the trailer last week, I noticed a little rust line on the frame about 1" above the bottom flange. Upon closer inspection, the web was cracked where the cross member/floor trusses are welded to the web. After a little searching I came across this post on the rv.net forum. The diagram posted there is exactly where my trailer cracked.

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/24529042/srt/pa/pging/1/page/1.cfm

Here's a bulletin from Lippert for a fix: http://www.lci1.com/LIP/0135.pdf



I ground the area and put a generous weld. My guess is the lateral forces on that section of frame are causing the lower chord of the floor truss to pull on the web. The web wasn't bent, but the weld quality was probably issue. Not to mention they probably need a stiffener there since the web is thin.

I don't know if I'll go through the hassle of adding the 2" tube struts across each of the three spring hangers. I've often wondered why they weren't laterally supported in the past.

Just thought I'd pass this on. It's no where near as bad as the pin box frame issues others have reported.

I'm going to contact Lippert and see what they say and/or offer.

Lograf wrote:Here's a photo of how I beefed up the area above the hangers when lifted my cat 2". I added a 12" wide plate above each hanger because I have seen several RVs with cracked webbing on the I-beams.

Nice work. Looks great!

Tater

Couldn't see any cracks when I checked last weekend, but I will keep my eye on it though.

It's just another thing to check - Scruffy will have to add it to his list. It keeps growing longer. I guess it's a good thing we have this forum to keep us up-to-date on this stuff.

Tater

If you drill a small hole right at the ends of a crack it can stop the crack from getting longer.

BobnPi wrote:If you drill a small hole right at the ends of a crack it can stop the crack from getting longer.

I just ground it down and welded it up beyond the extents of the crack on both sides of the web.

BobnPi wrote:If you drill a small hole right at the ends of a crack it can stop the crack from getting longer.

That's very interesting. Learned another thing I didn't know.

Tater

Like a window suppose to work. No cracks yet.