Trailing Arm Differences?

[D-n-Tyke]

I am trying to figure out if there are any differences between the C10 and C20 rear trailing arms. I have a 1969 C20 Suburban that I am changing over to 5 lug by putting in a 1971 C10 rear end. When I got the rear end it also came with the trailing arms. I want to clean up whatever trailing arms end up under the truck so if they are the same I will clean up the C10 arms at the same time I clean up the rearend and then just install it all at once. But if the C20 are different then I will need to pull htem off and clean them up and reinstall. Can someone help me out, are they the same or are the C20 ones beefier?

[Big Kev-O]

C20 trailing arms have support plates spot welded to the top and bottom of the arm. Dimensions are the same. They are a hair thicker because of the plates. C10 & C20 trailing arms are interchangeable. I'm using C20 arms and the only issue I had was my PorterBuilt track arm mount wouldn't slip onto the trailing arm because the support plates made it a tad too thick. I had to cut off section of one of the plates.

[SkidmoreGarage]

Not what you asked, but it sounds like you don't have both arms in front of you and I wanted to offer a suggestion.

Rust between the channels that form the I beam is pretty common. Pick the arms that are in the best shape before investing the time to clean them up. The c20 arms will not play nicely with aftermarket suspensions that mount anything thorough the u bolts. You will have to start modifying things.

[D-n-Tyke]

Thanks for the replies guys. Both sets I have are in pretty good condition, not much rust. Not planning on doing anything exotic in the suspension department. Probably lowering springs and maybe blocks. With that in mind I might stick with the C20 arms to maintain those support plates.