My 1967 Chevy K20 Build Thread

[Chaparralman1974]

2/4/2023
Rear Axle and Transmission Crossmember Cleaning
The rear axle itself was not that bad to clean. I have observed that the gear oil that leaks out of the differentials (both front and rear) when combined with dirt and left to bake in the sun for years, turns into a hardened mess that is like concrete! I found that the best way to tackle this is to use lots of oven cleaner and let it soak for at least an hour and then hit it with the pressure washer using a 0 degree tip. This blasts off all of the hardened grime and gets you down to just dirty metal. From there it is an easy operation with an angle grinder with multiple different types of wire wheels. I have decided at this point to stay with the original axle that came with the truck (Eaton HO52) for several reasons. First off, after a lot of thought and consideration, I decided that I don’t want to tackle the spring perches and jounce stops. I can do it, and it isn’t that hard to weld, but it really is just added work that won’t gain me that much. The axle itself is in good condition. The only real reason that I wanted to swap for the 14 bolt axle is so I would have matching 4.10 gear ratios front and rear. The reality is that the 4.57’s will honestly suit me fine for the intended purpose of the truck which is the occasional in town driver and not as a freeway machine. Another reason to stay with the HO52 is for originality. I really do want to keep the truck as original as possible. There is always the possibility that I can find a drop in 4.11 carrier sometime in the future. For now, I will most likely pull the drums and brakes off of the 14 bolt and will graft them onto the HO52. I ordered a set of 1971/72 HO52 hubs off of eBay that are setup for 9/16” studs, so the plan is to use those hubs, install new bearings and seals, and use the drums, hardware, and backing plates off of the 14 bolt in my build. That will give me the best of both worlds….an axle that has a bit more modern brakes, but is otherwise original.
The transmission crossmember was a bit of work compared to the axle. The grease and grime was like granite mixed with concrete! Furthermore, there was rocks, grease, and debris wedged into the different sections of the crossmember. This left me no choice but to grind down the rivets and clean each piece separately. The smaller pieces I let soak in kerosene to soften the grime, and the larger pieces I used extra oven cleaner on. After that, I hit everything with a wire wheel including the original bolts. I think it all turned out fairly well. Next up will be paint, and then I can begin reassembling the rolling chassis.