Opinions on rusty trailing arms

[Todd Hepler]

I've started a 72 GMC swb project with a couple of craigslist donor trucks. I have spent a couple of days cleaning up the frame and came across some questionable areas I'd like some opinions on.
Trailing arms - the drivers side is starting to rust in between the two halves to the point of swelling the arm - is it too far gone?


Also - the plate above the upper spring perches is doing the same rusty swelling as the trailing arm - what are these plates called and where can I get a pair?



Thanks for all your help
Todd

[Shyguy]

Sorry to say those trailing arms look pretty much gone to me. They are not difficult to find, there may be some for sale on the parts board.

Trailing arms also can be bought new from quite a few vendors.

If I remember right trailing arms for 67-72 trucks are the same, except those for 3/4 ton are a little stronger with some plates on them.

[Todd Hepler]

Thanks Shyguy - thats what I was thinkin.

I think you answered my next question - are swb and lwb trailing arms the same?

Todd

[Shyguy]

Yes they are, we put a set of 3/4 ton lwb trailing arms on my 1/2 ton swb frame. Some people call them control arms.

A good reference for these old trucks is LMC catalogs. I have one for 67-72 trucks and the years just before and just after. It is interesting how many parts will fit different years. Of course I rarely order from LMC.

[marenick]

I had the same problem with my frame above the springs. I ordered a section of frame from Bills truck shop (canada) and hired a welder/fitter to fit and weld the sections . He did a great job and you cant even tell it was repaired. it is hard to find a good frame up here so it had to be repaired. if you can get a better frame go for it but if not it can be repaired

[cam.man67]

Shot? Those have plenty of life left in 'em. The guy who painted my truck welds 1/4" steel to brace up rusty ones for a fraction of the price of a new one.

[Hottrucks]

check out my build my trailing arms are fresh out of the back of a NASCAR...yep they are a direct bolt in....the diff being that the front has a hine ( spelling ) joint instead of the rubber..to tell the truth I was worried about it being a rattle but they dont..best part $100 shipped to me

[big_al_71]

Mine were in 100% better shape than yours and I still replaced them,I went with these on my truck and could not be happier.....



http://www.earlyclassic.com/catalog....railing%20arms

[Todd Hepler]

Marenik - Im actively pursuing a donor for the spring perches/plates. When I took the rear coils off the upper spring hanger just crumbled on both sides - I guess I need those too!

Cam.man67 -Were you referring the trailing arms or the other part? The one trailing arm is swelling apart from the rust in between the two halves - I'm sure it won be long before it pops a rivet - the crusty spot is where the rust is making its way through the entire arm on both sides.

Hottrucks - enjoyed your build. The Nascar trailing arms are definitely t!ts!

big al 71 - I looked at a few places and saw similar prices.I only have $400 in the SWB frame/bed/misc parts and $500 in the donor truck(complete and original ac cab 72 gmc 350/350 minus bed - drove it home!) I'm trying to buy as little full price parts as possible - I may need to name this build the craigslist cruiser! Billsbowtie has a set for a great price that I'm picking up wed.

Thanks again everyone for your input and advice.

Todd

[cam.man67]

Yes, I was referring to the trailing arm.

[Jblackie47803]

Are you lowering the truck? I had the same problem with the rust above the springs. I used a c-notch kit to effectively "replace" the rusty area and provide a new mounting point for the spring.