Th400 Howls when slowing down?
Thread Starter
Melting Slicks
Joined: Sep 2002
Posts: 2,631
Likes: 0
From: Union City CA
Th400 Howls when slowing down?
The Transmission howls when Im deaccelerating, I dont know if it is b/c I pulled it out of a Big Van that has straight cut gears maybe? Or something else is screwed up with it.
Also, the car doesnt feel like it has the necksnapping acceleratiion like my old setup had with the tired old 350, now I have a 406. Even though I have not floored it yet, in either gear, but it should be able to produce somekind of thrust, or does it not b/c I may have some junk heads? I got the 406 rebuilt from an engine builder and he said he installed 2.02/1.6 valves which he said was the main thing in letting air flow in/out. BTW, this was with about 9.5-10 quarts of tranny fluid and it was leaking a little bit from the rear tranny seal which Im ready to change.
Thanks for the help C3 guys, Not that many members on the C4 side that have Th400, let alone problems with them. :nonod:
Also, the car doesnt feel like it has the necksnapping acceleratiion like my old setup had with the tired old 350, now I have a 406. Even though I have not floored it yet, in either gear, but it should be able to produce somekind of thrust, or does it not b/c I may have some junk heads? I got the 406 rebuilt from an engine builder and he said he installed 2.02/1.6 valves which he said was the main thing in letting air flow in/out. BTW, this was with about 9.5-10 quarts of tranny fluid and it was leaking a little bit from the rear tranny seal which Im ready to change.
Thanks for the help C3 guys, Not that many members on the C4 side that have Th400, let alone problems with them. :nonod:
Le Mans Master
Joined: Aug 2000
Posts: 6,362
Likes: 7
From: Brazos TX
Cruise-In IV Veteran
Cruise-In V Veteran
Re: Th400 Howls when slowing down? (Light84vette)
Does it howl when you downshift? Usually they will do that in first gear when deccelerating. As for not feeling as fast, it may be the torque converter. First gear is quite a bit taller than a 700R4 (if that's what you switched from) So you will notice that it doesn't accelerate as good because of that. First in a 700R4 is a 3.06 and a TH400 has 2.48. That will be very noticalbe. Also the TH400 uses more hp than a TH350 or 700R4 but you just may need to let the engine break in a little and get it tuned good. What cam do you have in it?
Melting Slicks
Joined: Apr 2000
Posts: 3,341
Likes: 6
Re: Th400 Howls when slowing down? (Light84vette)
Do NOT operate the car until this problem has been thoroughly investigated, and by that I mean don't even run the motor. If the tranny or the converter is truly howling, you have got big problems. This is absolutely not normal.
I could share some ideas and thoughts with you on the subject, but it would be of little value to you. You need somebody right there with you who knows his stuff to diagnose the problem.
I could share some ideas and thoughts with you on the subject, but it would be of little value to you. You need somebody right there with you who knows his stuff to diagnose the problem.
Thread Starter
Melting Slicks
Joined: Sep 2002
Posts: 2,631
Likes: 0
From: Union City CA
Re: Th400 Howls when slowing down? (45ACP)
Thanks for the help, it was howling when I only had 4-5 quarts in it ( :crazy: Yeah I didnt check into that even though the dipstick read full) But When I filled it up to 10 Quarts, I did not recall it doing this b/c I quickly put the car back on the stand b/c it was leakin due to a shotup rear tranny seal and the engine was hesitating upon 75% + throttle.
