Delvac ATF in latest of JWS 3309?

Sep 1, 2022
I feel so honored to finally be posting on BITOG after all my years lurking!!!

Got a 175k Volvo 2.5 late FWD CX90 to commute in… trans claims it’s a lifetime fill but many use JWS 3309 to drain and fill.

I get Mobile 1 Delvac Synthetic ATF by the case though…. Is it not 3309 but with just an Allison approval?
Sep 20, 2014
Seattle-ish, WA
No, Mobil JWS 3309 is a different fluid. That synthetic may work great there and I suspect it would; but I have no experience with that.

The transmissions on those vehicles are REALLY easy to service so you are in for a relative treat. You may want to have a plastic retaining collar and some o-rings on hand when you pull the return line on the radiator - the collar may break if you are not very careful and fresh o-rings do not hurt after this much time and mileage. A 3/4" OD piece of tubing will fit in the return orifice there and a few feet of it can then reach a container on the ground. It's even easier than the average oil-change since you don't need to lift or go under the vehicle.

If you do decide to go with 3309, last time I needed some the easiest/cheapest was to talk nicely to the parts guys at the local Toyota dealership. They gave me a case of T-IV for 20% off so it was a good deal. Toyota T-IV is re-branded JWS3309.

ETA: to clarify, T-IV is made by Mobil to a spec they developed at Toyota's request. The internal mobil spec number is "3309." They are 100% the same.
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