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TR5/TR250 TR250 trailing arm box section

BRSLimited

Jedi Trainee
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Anyone ever replaced the box section on the frame where the rear trailing arms bolt on? How bad a job is it? The entire rest of the frame is perfectly solid, Diff mounts arn't even cracked.
 
I worry about those parts of the frame, but haven't seen rust or cracks on mine yet. I've read about the issue and I believe Revington TR offers replacements to weld into the frame. If I had the body off, I'd probably consider it due to the articles I've read about the lack of internal strength where the TA brackets bolt on, lack of strengthening pieces, etc.
 
I plan on reinforcing the Diff mounts while I've got it apart, no cracks in them but a little extra strength can't hurt. My box sections are unfortunately rusted out and need to be replaced. But fortunately the rest of the frame is solid. Just don't know how bad of a job they are to replace.
 
Good idea to reinforce the differential mounts, and now is the time if the frame is bare. I have not replaced the box sections myself - although I have the bits if anyone needs them for a TR6 - but as long as you focus on making sure the geometry right and strong welds you should be OK.
 
I replaced the box section on the passenger side of my TR6.
BEFORE I cut the bad section out, I place a couple of steel I-beams across the width of the frame and used C-clamps to tighten them down. The I-beams kept the frame from twisting until the new section was welded in place.
Also, I did lots of prep work prior (grinding) to welding back in.
 
Great idea on the I-beam, never thought of that. My welding I'm not worried about as I have been welding for years and can make very good looking strong welds. Right now the frame is being used for doing the body work. Need to put in floors, rockers, B posts, and repair the A posts at the bottom front corners. Couple weeks and the body should be ready to come back off to start preping for paint, then I can tackle the frame. I'm going to send it out to get it blasted before I do anything else just so I can do any other repairs that show up but I don't think any will. I can take a pick hammer and tap all over the frame and get a nice clear ring not a thud.
 
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