Another transmission question.. easy answer?
Thread Starter
Instructor
Joined: Apr 2015
Posts: 238
Likes: 96
From: South Carolina
Another transmission question.. easy answer?
73 Convertible, the trans is a th400. Car has been sitting for years in a garage away from animals/elements and I have no reason to believe the transmission is bad. However the car was turned on maybe once every couple of years over the past 8 its been sitting inside.
Putting in a Vortec 350 engine and with the mods done expecting 420hp/tq or there abouts.
With the new engine my plans are to change the fluid in the transmission and put on a new torque converter and leave it at that. I feel a th400 should be able to handle 400+ torque just fine.
So my question for the more experienced here.
Does my above plan seem sound? If not, what would you do?
Putting in a Vortec 350 engine and with the mods done expecting 420hp/tq or there abouts.
With the new engine my plans are to change the fluid in the transmission and put on a new torque converter and leave it at that. I feel a th400 should be able to handle 400+ torque just fine.
So my question for the more experienced here.
Does my above plan seem sound? If not, what would you do?
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
73 Convertible, the trans is a th400. Car has been sitting for years in a garage away from animals/elements and I have no reason to believe the transmission is bad. However the car was turned on maybe once every couple of years over the past 8 its been sitting inside.
Putting in a Vortec 350 engine and with the mods done expecting 420hp/tq or there abouts.
With the new engine my plans are to change the fluid in the transmission and put on a new torque converter and leave it at that. I feel a th400 should be able to handle 400+ torque just fine.
So my question for the more experienced here.
Does my above plan seem sound? If not, what would you do?
Putting in a Vortec 350 engine and with the mods done expecting 420hp/tq or there abouts.
With the new engine my plans are to change the fluid in the transmission and put on a new torque converter and leave it at that. I feel a th400 should be able to handle 400+ torque just fine.
So my question for the more experienced here.
Does my above plan seem sound? If not, what would you do?
The TH400's will tolerate 500 ft/lbs of torque so its certainly capable of handling a Vortec 350. But why would you want to change the torque converter or the oil?
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
It's a roll of the dice after a trans sits more than 5 years. The top part of the seal dries out and the bottom is still coated with trans fluid but I have gotten many auto transmissions to live with a few simple tricks. Change the fluid and filter to check for moister. Than fire it up and add seal conditioner. Without a load, let it warm up and let it go thru the gears with the wheels off the ground. Let it sit over night and you should be good to go the next morning. Your biggest concern is a blown or leaky seal. Going thru these steps gives everything a chance to soften up and get trans fluid everywhere it needs to be.
BTW, change the input before installing the new motor.
BTW, change the input before installing the new motor.
