My rear Frame extension is failing

[Hobotrek]

Hello everyone, not really sure where to start haha. The drivers side rear frame extension is cracked at the weld and has multiple rust issues. Toyotas frame is fine, just the rear add on section. I discovered this by standing on the bumper to see the roof. (Felt the bumper drop about 2 inches.) When I bought it I knew about the rust and planned on patching, but now I am thinking on replacing the entire rear extension on both sides. While I am under there I am planning on beefing it up so I can tow a trailer (With brakes) without worrying. I have a few questions.

Has anyone ever dealt with something like this?

Did you Repair vs Replace?

Chinook owners, How difficult is it to remove the camper body??

I am thinking to get a good weld the body has to come off. I'd hate to have another Toyota up in flames on this forum. While the Chinook body is off I would paint the frame with some Good Por-15 or something.

Edited July 18, 2013 by Hobotrek

[waiter]

Just some initial thoughts;

Jack up the back so its even, then weld a couple heavy "L" beams maybe 3 ft long, across the bottom of the cracked area to reinforce it, then see if your able to run a couple beads to weld the cracks shut.

You alread seen the Flamed Toyhouse. That could have been sparks, OR radiation that just got nearby wood or fiberglass hot and ignited. Use caution.

JOhn Mc

88 Dolphin 4 Auto

[fred heath]

Looking at the amount of rust and particularly the rust hole in the frame rail I'm not sure you have enough "meat" to take a weld on the cracks.

I would take it to a good weld shop and get their opinion on the best fix.

Don't be surprised if major frame surgery is recommended.

[Totem]

Just curious... were you towing with this setup?

this could make me eat crow... hoping the answer is no

[MontanaChinook]

Yeah, my Newport has a similar, but not nearly as bad, issue. That area is just starting to sag. No rust, no cracks, but you can see, from inside the coach, that the floor starts slanting down a bit for the last 3 or so feet of the coach.

Let me know what you do...

I agree with waiter, if there's enough solid material, jacking the back up to level, and welding supports there seems like a good idea.

And YES, whoever does it, make sure they know how easily the whole thing can catch fire!

[zero]

Hello everyone, not really sure where to start haha. The drivers side rear frame extension is cracked at the weld and has multiple rust issues. Toyotas frame is fine, just the rear add on section.

I can't make out where the frame extensions join to the OEM frame. On my 78 Chinooks - there is a frame extension on each side and they bolt to the OEM Toyota frame with two bolts per side. But - even in perfect shape those extensions alone are not strong enough to support much weight. There is also a V-shaped support truss that goes between the two extensiions and attaches to the back bumper and ball hitch. One side on one of my Chinooks had been bent by someone backing into something - hard. It was near impossible to straighten when in one piece. So I cut it into three pieces, straightened the smaller sections and then welded it all back together. Was fine when done.

My 78 pop-up roof Chinooks were attached to the truck frame in five places. Two 1/2" bolts on each side frame rail and one carriage bolt in the front center that connects to a crossmember between the frame rails. Chinook used a stack of plywood squares to hold the RV body at the desired level.