518 questions

[ChallengerHK]

What would be a good max torque limit if I was going to install a lockup version of the 518?

Can the lockup trans be used as a non lockup trans, with no input from the third wire?

[Katfish]

If you don't connect the 3rd wire, it won't LU.
But why would you do that?  Benefit is lower RPMs and cooler operation.
Absolutely LOVE my 518.

[ChallengerHK]

A couple of the other sites I've been using to research this have expressed a surprisingly low torque number as being able to tear up the lockup feature (hence the first question above). If I exceeded that number, I'm wondering if I can just disconnect the inputs for lockup rather than having to find a non-lockup trans.

[Katfish]

Well LU should only occur at 55mph or higher.
So do you expect to throw a ton of torque at it while going 55mph and 1800rpm?

If set up correctly, the LU will disengage when you get on it.

[ChallengerHK]

I did a program on the GM 4l60E several years ago. Lockup was failing because it didn't disengage properly or fast enough. Result was having to replace the transmission. Trying to prevent a similar result.