I realize that that JWS3309 tranny fluid from Volvo is not synthetic. But, I was at Walmart and noticed that their Full Synthetic fluid has a JWS3309 rating. Any thoughts??

 

Yes you can find both standard and synthetic fluids that meet the JWS3309 spec. For example, Redline D4 is a fully synthetic ATF that cites being both JWS3309 and Dex III compatible but doesn't come right out and say its JWS3309... Since the Aisin transmissions that require 3309 are also used by Toyota, some folks simply shop for Toyota T-IV OEM ATF, others recommend Mobil's products which list 3309 directly. Unless you want a fluid that's better for extreme cold, you should be fine with standard but synthetic would be a nice upgrade as long as you are using a 3309 spec'd product.

 

Thanks, for the reply.

 

I just got my 04 XC70 with 110k and I haven't looked closely yet but does the transmission have a dip stick and fill hole? Am assuming it has a drain plug.

I'm considering draining the transmission oil and replacing it with synthetic. Will draining it drain all of the tranny oil or just a partial drain. I watch mars52 doing a flush so I guess draining it is just a partial drain. Is it advisable to flush the oil or just do a partial drain 3x? And is he doing it correctly?

Since its an AWD, what about the rear differential?

 

Use Mobil 3309 fluid and forget chasing all of the others.