GL truck update:
This’ll be a short one. I’m a little disappointed in what I discovered today. I started to tackle the the transmission and ran into a less-than-ideal situation.
To begin with, contrary to my last update, I decided not to torch the drum brake mounted to the tail shaft housing. It was too unique for me to destroy, I wanted to make that a last resort and save it for something in the future. In my search to get the thing apart, my thought was to remove the tail shaft housing and deal with it later. The tail shaft housing was also unique; it was secured with studs and nuts. I don’t recall ever seeing a GM transmission that didn’t have the housing bolted to the case. The studs were CRUSTY. I was so worried I would strip or brake something but alas- everything came apart! In my relief, I totally overlooked the bolt from the brake drum backing plate into the tail shaft. Six to eight smacks from a dead-blow hammer and I realized my mistake. The tail shaft housing had separated about 1/4” from the case at that point so in my examination, I’ll need to see if I damaged anything.
If that wasn’t enough, I opened up a huge mess. In one of my last posts, I mentioned the tiny amount of water that came out and how I wasn’t worried. I should have worried. Pictured below is the additional fluid/water combo that came out at the start of disassembly. I was happy to see that this is an eight-bolt pump case but that was about all I was happy to see. The rust made me cringe. Viewer beware- the pictures are disturbing. Most of the inside is rusty.
Initially I was excited- having been removed from a motor home, I was sure it hadn’t been messed with. The cooler lines were cut off (generally if the trans is removed because it’s shot, they’re not cut). All six check balls were in the valve body so I’m fairly certain this was a virgin transmission. I’m sure when it was removed, it was in great shape. There is plenty of material left on the bands and clutch packs so it feels like an even bigger let down.
As life goes, it’s good to have a back up plan. Years ago I bought a 1989 K3500 from a small waterpark in Chardon, Ohio, called Pioneer Waterland. I bought it for the 454 and 14 bolt rear end that I wanted for the Geauga Lake truck. I pulled both and unfortunately cracked the bell housing on its TH400. Ultimately the 454 cost too much to build so it’s in storage waiting for me to hit the lottery. I left the transmission in the truck and gave the whole thing to a friend for parts. Fortunately he still has it. Fingers crossed that water didn’t get into that one too. Hopefully I can get a good mix of new and used parts from the ‘89 to plug into this rock solid case. I’ll just add ATF though and forego the water.
Thanks for reading.