I just replaced the 455 in my 73 Riv. I pulled the trans with the engine, cleaned the outside of it up, replaced the filter and pan gasket, and reinstalled it with the good engine. I started by putting 6 quarts of fluid into the trans before starting the motor. My Chilton's manual for my 72 chev PU states that the refill capacity for a TH400 is 7.5 quarts. Seeing as though overfilling the trans can do more harm than underfilling, I erred on the low side and planned to top it off once everything was up to temp, checking it with the dipstick. Upon starting the motor, there is a horrendous rattle coming from the trans, and it won't shift into gear. I have put another quart in, theoretically bringing the volume up to 7 quarts of trans fluid, but the problem persists. On one attempt to put the car into a forward gear, it felt like it tried to engage, but the feeling was very vague. The rattle goes away after the engine has run for a minute or two, but the trans still won't go into gear. THe fluid level is still a ways below the "1 pint low" indicator. Soooo... 1. Is the dipstick reading accurate if the trans hasn't "worked" enough to create enough heat to warm it up? Or will it warm itself up enough just at idle? What should the level on the dipstick be cold with the engine off? 2. How much fluid will a stock Riv trans (TH400) take? Is the refill capacity listed in the Chilton's accurate, or does that assume just dropping the pan and not draining the converter? I did drain the converter, but I don't know if there was any residual fluid left in it. The Riv trans may be different than the truck trans, but that's all I had to go by. 3. My vacuum connection to the manifold for the trans could be better, but I thought it was "good enough". Would this prevent the trans from being shifted into gear? Even so, I can't imagine it would cause something to rattle, could it? I'm certainly no trans expert, so any advice would be appreciated. Nick
Nick, I would drop the pan again, and make absolutely sure that the filter pipe was all the way in to the case. It's very easy to put it in backwards, or not push it in far enough. You can even use 2 O rings on the tube. Make sure the tube bottoms out in the case. It sounds as if the pickup tube came out. Check it. You'll have to drop the pan, just save the new fluid in a clean container.
Fixed Thanks for your help. I dropped the pan, managing to keep all 7 qts of fluid in it (should have been a sign, I guess) and checked the pickup tube. Everything looked OK. I did replace the one O-ring with two O-rings, and put it back together without spilling more than a couple drops of fluid :grin: . This, however, didn't solve the no shifting/noise problem, although the two O-rings surely didn't hurt, much better than the stiff old single. The car still wouldn't shift, so I put another quart of fluid in it, at which point it DID go into gear, but the noise started getting worse. I pulled the tin cover from under the converter and noticed that the flex plate had been rubbing on it ou: . I customized this with a few well placed tweaks, put it back on, started it upn and the noise had disappeared. I then proceeded to put two more quarts into the monster before the level was up to snuff, for a total of 10 quarts. I was just apparently way low on the level. Now, we're back in business. :3gears: . Nick
