When mine busted it was from my stock 350 with a 2bbl also haha. I punched it, felt a slip and a clunk bang. Pulled the trans and the shaft was twisted. Looked like a piece of licorice Sent from my LG-H811 using Tapatalk
Yeah funny stuff indeed! That's never been my experience with them, quite the contrary in fact. I broke a TH400 with the same behavior I put one of my ST300's through, so go figure? I broke a Buick 8.2 rear with an ST300. That doesn't mean the Buick 8.2 is a junk rear end. It means I abused the HELL out of it, and the ST300 held up. If a healthy 455 can't tear one up and a 300-2 can, there must be something else at work here. Torque converters must be properly set up on the shaft or you'll bugger up anything. Something is definitely fishy about a stock 300 tearing up an ST300. lol!!! A common issue with the ST300 was the low band becoming neutralized when the pressure spacer fell out into the pan due to people not knowing you had to adjust it every 60,000 miles (30,000 with heavy duty use). Perhaps there were other issues people were having that I was never aware of because I never experienced anything but awesomeness from mine? Many people have had great experience with the ST300, even at the track, and behind a hell of a lot more power than a stock small block. I reckon it's all preference, but I was never impressed with the TH350 transmission with its crappy shifting patterns and extra parts to wear out (a stock TH350 doesn't perform nearly as well as a stock ST300), not to mention twice the power it takes to turn it vs the ST300. Look around here on this transmission forum and everywhere else for that matter to see a pattern with the TH350. This is not to say you can't get one to behave properly, because you can. The TH350 makes an excellent transmission when set up properly. It just takes more effort. Pros and cons abound with every transmission.
I loved mine. I dont know what happened to cause the shaft to twist but it was a fun transmission for sure. Wouldnt mind getting another Sent from my LG-H811 using Tapatalk
Sounds like the converter wasn't far enough on it or something. You have to make sure they're placed on the flexplate properly (clearance them so the converter is inside the trans completely). Or maybe the shaft was defective? I thought a TH350 converter would fit into one, but maybe not? This is unknown to me as well, since all my ST300's held up like champs. Maybe someone with more knowledge on these transmissions could chime in and answer. I made another post regarding this transmission to try and lure more information on this subject. The main 'weakness' of this transmission that I experienced was that it is a bit more sluggish at taking off from a dead stop than 3 geared transmissions, but after it gets rolling a bit, the benefits of using one become clear. This is why I wouldn't recommend one for max effort at the track, though there have been reports of it doing just fine here as well with a higher stall converter. It trades a little on the '60 time for better MPH at the end. This backs up my statement on how it behaves. The best part of using one is it puts more power to your wheels, since it takes less power to turn than other transmissions. The kickdown/passing is unbeatable on these transmissions! For a cruiser or street fun, it's hard to beat. Not to mention that you could get one for next to nothing because many people want better gearing for better '60 times. A stock rebuild kit is dirt cheap, and the stock parts will hold up to a lot of power. If you ever decided to get another one, you wouldn't be out of much money should you change your mind and replace it with something else. These transmissions work great with 3.23 gearing (the '68 GS350 came default with that ratio and the ST300 from the factory). If you do decide to get one, report your findings (good or bad). It would be a great contribution to this forum.
Who knows what happened. It was the OG transmission the car came with and dont think it was even separated from the motor. I bought the car with 58k untouched from a lil old lady. But you're absolutely right about kickdown/passing gear. Holy crap that was fun. Sent from my LG-H811 using Tapatalk
I'm still here, lately working with a 250' solar array that heats and lights the house. Those 75-79 Cad ECUs keep coming here for repair. And switch pitch hasn't gone away yet. Bruce Roe
Perhaps this may offer an explanation as to why yours (and others) "ST300" broke: http://www.v8buick.com/showthread.p...00-2-speed-transmission&p=2611631#post2611631
