Re: 2006 XC90 4.4 v8 High mileage transmission fluid change

[EuroTrash45]

So my new to me xc90 v8 has 173k miles on it and the service history of anything besides oil changes is unknown on it. Here in the next few weeks i had planned to begin servicing all of the fluids in the vehicle as it has sat for a long time, im not too worried about the differential and engine as much as I am doing the transmission. I know the drain and fill procedure as it is very close to the toyota procedure for damn near all of their transmissions but my worry is how the transmission will react to the new fluid. It doesn't seem to have any trouble shifting besides some funky torque converter lockup due to code p074400 and a thing in 2nd or 3rd where the rpms stay the same but the truck still pulls and gains speed (no slipping felt). What kind of risk am I looking at if I service the transmission and will I even get any benefit from it?

[ggleavitt]

JWS3309, however you want to do it (gibbons radiator hose pump-out or drain/fill). Never harmful to try new fluid on these transmissions when things don't act right. Likely you're in the SN range for a valve body issue with your 2-3 flare, even that often gets better with new fluid.

12 quarts easy on a first fluid change before you'll see it ruby red. I've used as much as 16 quarts for the first and 12 for subsequent changes, you really want as much new fluid in as possible (capacitym is approx 8 quarts). Swap over time or in one shot, you'll want to reset the fluid counter when you're done so the TCM knows there's new fluid in for monitoring, especially if you intend to do any towing.

I've used Mobil JWS3309 as well as Toyota T-IV in my vehicles over 15 years. Both have a history in the 5 and 6 speed transmissions and they're not that pricey. There are other "compatible" fluid alternatives out there, I'm only noting what I and many other V8 owners have used.

[EuroTrash45]

Appreciate the help, never got a notification that anyone replied and I honestly kinda forgot I posted lol. Being a toyota line technician myself I actually happen to have a ton of the toyota T-IV that I've aquired over time. I'll start this weekend with pumping the fluid out of the transmission using the trans flush machine we have.