2008 S80 transmission swap

PA08S80 · Post by **PA08S80** » 14 Feb 2023, 04:03

I'm going to need to change out my transmission soon as mine is over 170,000 miles and is showing it's age. I have the V8 and was wondering if the newer 8 speed TG-81SC would be an option and what all would need done to get it to work? I'm thinking that this would be the same as the one in the vehicle and a possible flash would be the only thing required unless the TC would be different due to the V8 never having the option? I'd imagine it's the same as the others but want to confirm. Also, since the Volvo name carries a premium cost and GM is more readily available in my area, would the GM variant (if they have an AWD version) be an option?

dikidera · Post by **dikidera** » 14 Feb 2023, 04:15

The first issue is physical fitment I would imagine, including the driveshaft lengths. Then the software side.

PA08S80 · Post by **PA08S80** » 14 Feb 2023, 10:08

I was under the impression this is the exact same transmission as what I have with different internals...

dikidera · Post by **dikidera** » 14 Feb 2023, 11:35

I know people have swapped the 5 speed auto for the 6 speed auto when it was not offered. I would imagine with dedication, it can happen...provided it fits physically and the software side is worked out.
In another thread it was mentioned that final drives can throw off the CEM or ABS.

If the gearbox you had previous was also 8 speed(I would imagine it isnt) then the final drive will likely be different.