MY 1969 PETE ON YOUR STEPDECK? SHOT IN THE DARK!!

It must be said, you all lost me with your tech talk on older trucks.... but keep them pretty pictures coming

 

The last two you posted are actually factory Kenworth's, both are Kenworth 963's, heavy duty off-road rigs, primarily found in the middle east as ultra heavy oilfield rigs out where there are no roads. The first photo is an earlier photo of a truck built by a Canadian custom shop, Quality Custom of Brampton, Ontario built it. The yellow and black as well as white and red were built by the Blastolene Brother's, the remaining few I don't know much about. I've seen the heavily chopped, channeled, and sectioned one that's as a rolling chassis, but, I can't remember the shop building it, but, I believe it's out of the PNW.

Regarding corrosion, yes, there were issues in the time period your truck was built with frame corrosion when steel crossmembers were mixed with aluminum frames (as well as some partial aluminum crossmembers and steel frames). As the trucks ran up and down the road vibrating, the coatings on the frame and crossmembers would eventually chip off. As salt, snow, and rain began to seep in between the crossmembers and frame, the corrosion process would begin, and it was typically the aluminum that got eaten up more severely, even though steel is a more reactive medium, as the aluminum is not near as dense a material, just less material had to be eaten. Originally, truck manufacturers for the most part used aircraft grade aluminum in their frames but found these were particularly susceptible to corrosion. If you see corrosion that looks like the frame is chipping apart (not pitting, but, like when you break apart a shale rock and can see all the striated layers) that would indicate an earlier aluminum frame that is aircraft grade aluminum. After the manufacturers found this issue, they began to alloy the aluminum frames to handle the corrosion better.

Personally, being a SoCal rig, I wouldn't be tremendously concerned about severe corrosion. If, however, you'd like to check and be sure, pull one crossmember out at a time and inspect for corrosion. Always get new hardware though, grade 8.

 

This here is downright "mechanical blasphemy"!! LOL

 

You might enjoy some of the "mechanical blasphemy" I've been associated with (closest you'll ever get to a portrait of me):

https://www.facebook.com/video.php?v=10156102008085472