[benoit454]

IMO nothing. I think it's a myth without lockup they burn up, if so then why are they reg. th350's that don't lock up, been around for years and still going?

From what I read you cannot put a regular th350 non locvk up TC on a lockup trans and vice versa.

However if you are going to put in a 700anyways, you could do the lockup now and just reuse it on the 700r4.

IMo I'd ditch the lock up and ditch the od. Unless you run some good gears out back like some 3.73's or 4.10's then I could see using od.