1998 FWD s70 w/o turbo, transmission question

doofygy1987 · Post by **doofygy1987** » 01 Jul 2012, 21:23

what is the difference between a transmission assembly for a turbo and a non-turbo 1998 s70?

why I ask. I may be able to come into an s70 for next to nothing and it has some transmission issues. I am trying to calculate the cost of a worst case scenario (replacement) and the only remanufactured/used trannys i can find are for turbo FWD s70s.

any info would be helpful

JordanW · Post by **JordanW** » 02 Jul 2012, 11:33

Auto trans or manual trans?

As for the auto, the only difference between the turbo and N/A autos is the final drive ratio; however people have used them interchangably. You should be able to pick up a used auto trans for around $350 depending on mileage.

Post by **jimmy57** » 02 Jul 2012, 12:12

The final drive ratio is different as mentioned and the TCM for the NA engine with a turbo gearbox will set codes (wrong gear ratio code) due to that.
The ratio is numerically lower and will make a NA engined car a real slug in acceleration. You can swap the TCM from a turbo car but your shift points will always be too soon (shifts early) as the turbo ECM is expecting a higher torque signal from ECM and the mapping in software for shifts will shift it too soon as a result. It may even set codes due to seeing too high throttle opening with too low of a torque signal.

Post by **jblackburn** » 02 Jul 2012, 12:16

A transmission from a NA 96-97 850 will work just as well as a 98 if that increases your odds of finding one.