Subaru CVT Drain UOA

[MoneyJohn]

Hello folks,

I just had the CVT drained and filled on my 2015 Subaru Forester. I sent a sample for oil analysis. This is the first time I’ve done this since the dealerships weren’t willing to help, so I took it to a Subaru specialist shop.

I’ve attached the oil report. I’d love to hear your thoughts!

 

[fantastic]

Yeah, dealerships like to do warranty work. Looks like it was a good time to change it out.

 

[SoupSandwich]

Apologies if I missed it on the report - what was the mileage on the CVT fluid?

 

[himemsys]

Hello folks,

I just had the CVT drained and filled on my 2015 Subaru Forester. I sent a sample for oil analysis. This is the first time I’ve done this since the dealerships weren’t willing to help, so I took it to a Subaru specialist shop.

I’ve attached the oil report. I’d love to hear your thoughts!

View attachment 307223

This appears to be the factory CVT fluid, so 86k miles on the fluid. That might explain the high silicon? Could be factory sealers that only just now got washed out? Or perhaps Subaru uses silicon as an additive in their CVT fluid...

If we knew the virgin TAN and oxidation, it would be really helpful in determining how much life was left on this fluid. But the 1.76 TAN does not look bad at all, and the 44 oxidation seems more than high enough to justify the fluid change.

Honda CVT fluid starts off at .5 TAN and 35 oxidation. OAI recommends TAN climbing no higher than 3x-4x and oxidation no more than 20 higher than virgin. Based on that, it appears as if this oil was changed at the right time.

 

[MoneyJohn]

Apologies if I missed it on the report - what was the mileage on the CVT fluid?

86024 and approx 11 years 1 month.

The report is not like Blackstone's. Its under the sample information -> Lube Time.

 

[MoneyJohn]

This appears to be the factory CVT fluid, so 86k miles on the fluid. That might explain the high silicon? Could be factory sealers that only just now got washed out? Or perhaps Subaru uses silicon as an additive in their CVT fluid...

If we knew the virgin TAN and oxidation, it would be really helpful in determining how much life was left on this fluid. But the 1.76 TAN does not look bad at all, and the 44 oxidation seems more than high enough to justify the fluid change.

Honda CVT fluid starts off at .5 TAN and 35 oxidation. OAI recommends TAN climbing no higher than 3x-4x and oxidation no more than 20 higher than virgin. Based on that, it appears as if this oil was changed at the right time.

Thank you for a helpful reply.

I plan to change the fluid again in 2/3 years. That time, I will ask them to give me virgin oil sample to run with the drained oil sample.

 

[thetricky]

Sweet, another person not following Subaru’s “filled for life” guidance.

Here is my cvt fluid experience if you are interested:

T

Thread '2014 Subaru outback Amsoil CVT 149k Odo, 29k OCI'

Jan 13, 2025

Decent report on the current Amsoil CVT fluid and I've also attached the reports from when I got the car. The 59k change would have been Subaru fluid, then Amsoil until now. Any guesses on the silicon in the current sample? Pretty cool dataset to get out there, especially for anyone on the fence about aftermarket fluids. When I took this sample I did do two consecutive drain/fills with HPL. To be honest, the Amsoil felt awesome when warmed up, however, the trans always had a slight shudder when cold, under about 35-40F. Nitpicky I know, just my observations.

• thetricky
• Replies: 13
• Forum: Gear, Transmission, Hydraulic oil analysis

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[SubieRubyRoo]

Looks pretty uneventful, but certainly didn't hurt to change it out. Well under 1ppm Fe/1k miles, and while I haven't done mine yet I surely hope it will be that low except mine is the TR690; don't remember seeing any used oil analysis on those.

OP, did you use Subaru CVT fluid or another brand? I'll be using @High Performance Lubricants CVT fluid, a few others here have used it so far with no complaints I've seen.

 

[crashz]

Looks like high silicone is normal.

 

[MoneyJohn]

OP, did you use Subaru CVT fluid or another brand? I'll be using @High Performance Lubricants CVT fluid, a few others here have used it so far with no complaints I've seen.

The shop used Subaru CVT fluid. They used to use Motul in the past but stopped using it as according to them there is no replacement for Subaru CVT fluid.