Dexron VI in my Subaru Forester XT

[dx92beater]

I have been draining and filling my Forester XT with Dexron 6. Just how backward compatible is it with transmissions that were intended to run Dex 3?
The vehicle is a Subaru Forester XT (turbo) with the 4EAT transmission. I am trying to reduce driveline losses.

I can tell you that the shifts are pretty hard with it and when I did a full throttle down the road it felt like it locked up in 3rd and barked the tires loudly. The dipstick on this vehicle is super hard to read so I can't be sure if it's incorrect fluid level or that the trans just hates Dex6 or if the TCU needs time to adapt.

Thanks

 

[dx92beater]

Forgot to mention it is the earlier SG FXT. It's an 04. 03-05 Foresters were specced for Dex3.

 

[Hollow]

Subaru never listed DexVI as an appropriate fluid and informed me not to use it in my 4EAT vehicle.

Dex III up. ATF-HP is supposed to be backwards compatible to the old Dex III vehicles.

 

[dx92beater]

Originally Posted By: Hollow
Subaru never listed DexVI as an appropriate fluid and informed me not to use it in my 4EAT vehicle.

Dex III up. ATF-HP is supposed to be backwards compatible to the old Dex III vehicles.


Interesting that they actually warned you about it. Thanks for the help. I am going to probably just go with the ATF-HP then. It's not so expensive actually.

 

[Linctex]

Originally Posted By: dx92beater
I can tell you that the shifts are pretty hard with it and when I did a full throttle down the road it felt like it locked up in 3rd and barked the tires loudly.


Yikes!

A really good transmission shop can reprogram it, but its cheaper to just change the oil

 

[Hollow]

Originally Posted By: dx92beater
Originally Posted By: Hollow
Subaru never listed DexVI as an appropriate fluid and informed me not to use it in my 4EAT vehicle.

Dex III up. ATF-HP is supposed to be backwards compatible to the old Dex III vehicles.


Interesting that they actually warned you about it. Thanks for the help. I am going to probably just go with the ATF-HP then. It's not so expensive actually.


Indeed. I emailed both Valvoline and Subaru support to inquire about their DexVI use in my DexIII spec 4 speed auto (archaic and indecisive but about bulletproof transmission when serviced once in a while). Valvoline said it was absolutely fine and Subaru said absolutely not.

Instead I went with Maxlife ATF which is a Dex/Merc fluid. Been running that for pushing 90,000 miles now, car shifts same as it ever has.

 

[NateDN10]

Dexron VI is a much thinner fluid. IMO you'd be better off with one of the "universal" ATFs like Maxlife or Mobil1.

 

[4WD]

The M1 might be thicker but thought Maxlife Multi vehicle is really close ...

 

[slacktide_bitog]

It will probably be fine

My choice would be Maxlife or Castrol Full Synthetic ATF

 

[4WD]

Maxlife is slightly thinner than Valvoline Dex VI (use it in my Cruze)-
I use Castrol MV in 4L60e but getting really hard to find.
If I had something pre dating Dex VI - I'd be all over Mobil 1 synthetic ATF.

 

[dx92beater]

Awesome posts, thanks.

 

[nthach]

Originally Posted By: slacktide_bitog

My choice would be Maxlife or Castrol Full Synthetic ATF

MaxLife will be thin compared to Subaru ATF-HP(or Nissan Matic-J) starting out - but I've used it in a friend's old Forester that was speced for Dex-III and it shifted just fine. Subaru's automatics are identical to Nissan's 4/5 speeds, seeing how Nissan once had a stake in them.

 

[anl0109]

I used blue-bottle Valvoline Dex/Merc fluid (recommended by Valvoline for Dexron-III applications) and it worked great in terms of shifting and fluid condition (color) whenever I drained it which was at or close to intervals listed in the owners manual. The vehicle was 2002 Forester L with N/A H4 and 4EAT. I've never tried any other ATF in that car.