been researching for about a month now and just want to make sure i have all the facts. For us auto guys doing the ls motor swap are there any other tranny options besides the
t56 and th400. Such as our 5at, 4l60,4l80,6l60,6l80 or anything else. I would like to keep my car automatic but if there arent any options i would probally end up going t56 since there isnt a overdrive with the th400.

 

Best bet man is to contact sikky or hinsen supercars and ask them directly

 

alright thanks man. yea sounds like no one could get anything else to work besides those two.

 

I've spent a lot of time on here and ls1 forums, you would need to use either of the ones you named or any 4l or T transmissions. Our 5AT would be absolutely destroyed by any motor as powerful as an ls1, so that is a no go. Just go with a used motor/trans combo if you want to save a little money on the build since it's going to get expensive.

 

yea im definetely just going to start off with a used motor/trans. I figure 6k for that and another 4 for the sikky kit. A lot more better use of 10k than going tt. so the 4l60 will fit? do you know anyone that has went that route?

 

I have seen a Z build awhile back and he did have to make some room for his trans I believe

 

you could probably do it with a full standalone for the lsx and what ever trans you wanted to swap into the car, however you would need to run your stock wiring harness as well in order to keep everything else such as headlights, power locks/windows, ect. which would not be that hard, the hardest part would be having a cluster fabbed up for a new set of guages to run off of the standalone

 

you would also have to run a seperate ignition switch or splice into the oem

 

Did you ever complete the build and could you find a auto transmission to fit trying to do a ls3 auto tranny and advice ?

 

I'd just look at the 4L60E tbh, you know it bolts to the LS, it has plentiful standalone controllers. The 4L60E fits in the tunnel, folks have swapped it before. But depending on how much power you're wanting to make (it will hold all your power if NA) then it might not hold. A built 4L60 can take about 600whp all day long without issues, a stock one you really don't want to put more than about 400whp into it. The biggest thing though is to put a huge transmission cooler on it, that will help a LOT.