TH-350c with lockup question

[lckycharm713]

im looking to by this chevy s10 with a v8 set up in it. i know this is not the s10 place, but in the past, i know this is the place to ask these questions. this truck has a 350 motor and a TH-350C with lockup trans. what i read, its the same as a turbo350 trans with a lockup. im not sure what it is. does anyone know and can help me out. whats the Durability of them? the guy told me it has a shift kit in it. the truck has never been started yet, it still needs some little stuff done to make it road ready. what i take it its like a 4th gear. i dont know, all i know is that a reg. 350 turbo is a 3speed. please help

[balls_to_the_wall]

a lockup? Would this be like a direct drive, it locks it in to a 1:1???

[lckycharm713]

Originally Posted by balls_to_the_wall

a lockup? Would this be like a direct drive, it locks it in to a 1:1???

i have no clue, thast why im asking here

[camaroguy26]

I'm no expert and can't tell you exactly, but it's like an extra gear or an overdrive if you will. The torque converter locks up and it's supposed to be the 1:1 like balls_to_the_wall is talking about, or is the turbo 350 a manual? lol I'm bad with transmissions. I just know lock up converters make it 1:1, it's good for street use if you have a high stall converter and lower rearend gears, it'll give you more gas mileage. the shift kit will make it shift harder so it doesn't slip into gear and burn the gears like a normal transmission would. It will help the tranny last longer. But if I'm right I heard the Turbo350 trans is a good one. I'm sure someone else can give you better input though.

[instantkevin]

that's partially correct. but lockup is not when the final drive ratio is 1:1. Third gear is normally a 1:1 gear; for every one rotation of the engine, there is (not exactly, but close) one rotation of the wheels.

Lockup is when the torque converter, which connects the engine and trans together, is spinning at the exact same speed as the engine. the converter will always spin slower than the engine if it is not locked up, therefore the wheels spin slower than the engine, therefore decreased gas mileage. when it is locked, there is no slipping.

read this....http://www.tciauto.com/tech_info/faq.htm#8

then click on "Converters Explained"

if you do a search on google you can find many places where it is explained in lamens terms.

http://auto.howstuffworks.com/torque-converter3.htm

[89IROC&RS]

bingo

basicly the lockup feature makes your automatic tranny operate like a manual tranny when you are cruising at a constant rpm on the highway.

automatics are a fluid coupling drive, they are not physically linked to the engine ever. they operate on the idea of two fans in a fluid producing torque to spin the drivetrain. so because it is based on fluid there is always some slippage. this slippage causes higher engine rpms for a given speed, higher trans fluid temps, lower gas mileage and all that jazz. the lockup feature is an internal clutch not unlike the one used in a manual transmission, that is activated by an electronic solenoid and locks the engine to the transmission in a physical link that has zero slippage for lower engine rpms, lower trans temps, and better gas mileage.

[lckycharm713]

a bit hard to understand but im getting the point. would you say its a good trans for this truck. im sure it has power and alot of speed. from what the guy tells me the engine is built reallt good. is this a tranny i want with this motor set up? i want it to rip through gears snapping my neck back and spinning tires as a reg th-350 or a th-400 would. what you think? ill be honest, if i get this truck and it has a bad set up that i have to rip out this tran and replace it with the reg. tubro 350 i have, i have to take the complete engine and trans out, then it be like starting from the start. i dont want to do that. if that was the case, i would put the set up i have now in the s-10 i own.

[89IROC&RS]

sounds like an awesome match for the truck. the tranny itself will operate just like a normal TH-350 would, there is nothing different about the internals of the tranny. The difference is in the torque converter itself, and the lockup should only kick in at highway cruising, meaning youll probly never even notice its working, but it will be.

[lckycharm713]

good stuff, thank you. lets hope i can get this so i can pull the motor from my friends shed with the wrong pistons in it huh.

[balls_to_the_wall]

Ahh ok, i wondered about the torque convert, but was to lazy to edit the post, plus didn't have time. Harvest is a bitch. good info fellas

-Ryan