5 year issue with shifting s40

[cichy1012]

2005 volvo s40 awd turbo.
when im slowing down into 1st it shifts super hard. sometimes when shifting up, it will shift hard. occasional service transmission light will come on.
It’s been doing this for 5 years right after I bought it. In the winter its non existent. fluid looks good. any suggestions or experience with this?

[Krons]

Sounds like a valve issue. Have you changed the fluid? How many miles on the fluid?

While a visual check is helpful if the additive package is shot and viscosity is off you won’t be able to see it.

[cichy1012]

Haven’t ever changed it. And not sure if it’s ever been changed.

[Krons]

Do a drain and fill and see if it improves. If fluid is still reddish color could do a transmission cooler return flush. Drain and fill is better if very dark brown.