Long term results for 2001 V70 auto transmission drain and fill

[volvolugnut]

This is a long report on my experiences with drain and fill of my Aisin AW50-50/51 transmission. This report may be helpful for other considering a drain and fill process.
My 2001 V70 with Aisin AW50-50/51 automatic 5 speed had a rebuilt transmission installed at 168K miles. It was filled with Mobil 3309 ATF. By 201K miles it started to sometimes have rough shifts from 1 to 2 and 2 to 1. Occasionally P1618 and P0810 codes would be set. These codes could be cleared and may not reoccur for months. I put off doing a fluid change because it seemed stable.
In December 2023 at 208K miles I started a drain and fill program on the transmission. My process was to drain the warm or hot transmission fluid from the bottom plug, measure the removed fluid, and refill with fresh fluid. After about 100 miles of normal driving, I would repeat the drain and refill cycle. My initial plan was to use MaxLife ATF as a flush fluid for several drain cycles and then switch to the preferred Mobil 3309 ATF.
I created a simple Excel spreadsheet to help track and calculate the percentage old and new fluids.
After the first couple drain and fill cycles, the shifts seemed to improve as dirty fluid was replaced with new. Transmission service codes were not set. My research said the full fluid content of the transmission is 7.5 quarts. I consistently drained 3.68 quarts.
After 4 drain and fill cycles I learned from MVS that MaxLife ATF has lower viscosity than Mobil 3309 or the Volvo recommended ATF. MaxLife ATF is 5.9 cSt at 100 C. Mobil 3309 is 7.1 cSt at 100 C and Toyota T-IV (recommended) is is about 7.3 cSt at 100 C. I added to the spreadsheet a calculation for the average viscosity of the combined fluids.
After the 4th drain and fill with MaxLife, the percent of MaxLife with lower viscosity reached about 90% and the viscosity averaged 5.98 cSt at 100C, I began to notice hard shifts again and the return of the P1618 and P0810 transmission service codes. At that point I stopped adding MaxLife and started adding Mobil 3309.
After the 5th, 6th and 7th drain and fill cycles, I continued to get transmission service codes of P1618 and P0810.
By the 7th drain and fill cycle, the shifts seemed to be getting better. New Mobil 3309 ATF was now about 85% and average viscosity was 6.93 cSt at 100 C.
After the 8th, 9th and 10th drain fill cycles, the shits continued to improved and I had no more transmission service codes.
After the 11th drain and fill cycle, the percent of Mobil 3309 reached 96% and average viscosity was 7.05 cSt at 100 C. I decided this was good and stopped the drain/ fill cycles. Since then shifts have been good and no transmission codes set for 350 miles.
At least one post of MVS stated the P1618 and P0810 codes were a death sentence for the transmission. At least in my case that seems to be incorrect.
I hope this report will be useful to others. I can share the spreadsheet if anyone cares to see it.
volvolugnut

[matthew1]

Beautiful documentation and context, VLN.

[Oro]

Good to hear you are happy w/your results. Have you done anything to address the underlying issue - valve body and solenoid wear, varnish, and seal degradation? That would be helpful going forward, I think. A fresh fill starting to shift oddly that quickly is indicative of something a little more going on. Also, have you checked the upper and lower engine and transmission torque struts? I’ve found that to have a slight impact on shift quality.

If someone is interested in how efficient multiple drain/fills are, here is a fractional dilution calculator I created several years back for a Lexus forum. It is set up for a “typical” 9 qt. system and a 3qt drain/fill. Efficiencies will be similar with any numbers around that; it does not take fine-tuning to get an intuitive feel for the declining results.

https://docs.google.com/spreadsheets/d ... q3E54/edit

The idea behind this is to show the benefit of doing 10 to 12 quarts through at once - it will save quite a bit of money and ecological waste vs a vastly higher number of individual drains and fills.

Another point - viscosity will be the same for any “genuine” T-IV - Volvo, GM, or Toyota when compared to 3309. All are blended in the same batches in Exxon Mobil refineries. Any variation is test equipment or batch variation. Here’s an excellent point; a head-to-head lab test of Japanese (Mobil) blended Volvo fluid and North American Toyota T-IV. Identical, down to viscosity (7.5cSt @100C in this test). Similar.

https://bobistheoilguy.com/forums/thre ... t4.341182/

Here’s the PSDS for “Japan” sourced T-IV, it’s blended by Mobil to their JWS3309 specification.

http://southcentral.edu/webdocs/safety ... 20T-IV.pdf

I have currently three vehicles using this same transmission, and two in the past. I’ve had occasion to observe using GM-IV, T-IV, 3309, and some others over about 1/2 million miles.

[volvolugnut]

About 500 miles now since the last drain and refill. Shifts continue to be smooth and no transmission service codes. If this good performance continues, I will not investigate valve body or solenoid repairs.
volvolugnut

[volvolugnut]

Now 1500 miles since the last drain and fill cycle. Still have smooth shifts and no codes set for Service Transmission. I may have a slight flare in 2 to 3 shift some times. I can't decide if it is real or imagined. Now 43K miles on this rebuilt transmission.
Still very successful work, in my opinion.
volvolugnut

[Krons]

Another point - viscosity will be the same for any “genuine” T-IV - Volvo, GM, or Toyota when compared to 3309. All are blended in the same batches in Exxon Mobil refineries. Any variation is test equipment or batch variation. Here’s an excellent point; a head-to-head lab test of Japanese (Mobil) blended Volvo fluid and North American Toyota T-IV. Identical, down to viscosity (7.5cSt @100C in this test). Similar.

https://bobistheoilguy.com/forums/thre ... t4.341182/

Here’s the PSDS for “Japan” sourced T-IV, it’s blended by Mobil to their JWS3309 specification.

http://southcentral.edu/webdocs/safety ... 20T-IV.pdf

Doesn’t the Volvo fluid have additional friction modifiers for its software in the Aisin making it effectively less slippery? That was shared elsewhere on the forum where LubeGuard HFM would improve standard 3309 fluid.

[Oro]

Another point - viscosity will be the same for any “genuine” T-IV - Volvo, GM, or Toyota when compared to 3309. All are blended in the same batches in Exxon Mobil refineries. Any variation is test equipment or batch variation. Here’s an excellent point; a head-to-head lab test of Japanese (Mobil) blended Volvo fluid and North American Toyota T-IV. Identical, down to viscosity (7.5cSt @100C in this test). Similar.

https://bobistheoilguy.com/forums/thre ... t4.341182/

Here’s the PSDS for “Japan” sourced T-IV, it’s blended by Mobil to their JWS3309 specification.

http://southcentral.edu/webdocs/safety ... 20T-IV.pdf

Doesn’t the Volvo fluid have additional friction modifiers for its software in the Aisin making it effectively less slippery? That was shared elsewhere on the forum where LubeGuard HFM would improve standard 3309 fluid.

Volvo branded fluid is Mobil 3309, re-branded. It has nothing added to it. Aisin spec’s the fluid, Volvo does not. This is a myth that has been handed around but lab analysis shows it to be incorrect.

Lubegard will add additional friction modifiers. It can be used to boost worn-out fluid if you like. Putting in fresh fluid is a better idea. I in fact do use Lubegard additive, but for the anti-wear and ester base oil (cleaning, seal conditioning). Excess FMs will do no harm. Too few, will do harm.

[canicallyourose]

interesting observations about the viscosity differences between fluids. i used maxlife in my 850 transmission once and noticed some hesitation afterwards - maybe the lower viscosity was the culprit? switched back to oem fluid and it seemed happier.

[dikidera]

Another point - viscosity will be the same for any “genuine” T-IV - Volvo, GM, or Toyota when compared to 3309. All are blended in the same batches in Exxon Mobil refineries. Any variation is test equipment or batch variation. Here’s an excellent point; a head-to-head lab test of Japanese (Mobil) blended Volvo fluid and North American Toyota T-IV. Identical, down to viscosity (7.5cSt @100C in this test). Similar.

https://bobistheoilguy.com/forums/thre ... t4.341182/

Here’s the PSDS for “Japan” sourced T-IV, it’s blended by Mobil to their JWS3309 specification.

http://southcentral.edu/webdocs/safety ... 20T-IV.pdf

Doesn’t the Volvo fluid have additional friction modifiers for its software in the Aisin making it effectively less slippery? That was shared elsewhere on the forum where LubeGuard HFM would improve standard 3309 fluid.

Volvo branded fluid is Mobil 3309, re-branded. It has nothing added to it. Aisin spec’s the fluid, Volvo does not. This is a myth that has been handed around but lab analysis shows it to be incorrect.

Lubegard will add additional friction modifiers. It can be used to boost worn-out fluid if you like. Putting in fresh fluid is a better idea. I in fact do use Lubegard additive, but for the anti-wear and ester base oil (cleaning, seal conditioning). Excess FMs will do no harm. Too few, will do harm.

And can you maybe shed light on why a big drain and fill transforms shifts but only for a few miles. It isn't just adaptations I think. Last year after a huge drain and fill, for a brief moment I had the fastest, smoothest shifts that last just a few miles, after which they go back to how they were.
I mean even with sticking solenoids, how did new fluid affect the transmission in a positive way seemingly curing it.

[ignatz]

Just a note on the 2001 Volvo V70 transmission. My 01 V70 2.4T made it to 228,000 miles when a small slice of an exhaust valve broke off, rattled for 2-3 seconds and then misfired. Luckily I was only 4 miles from home and soon found #3 had no compression.
The transmission in this wagon was original with the car shifting in neutral at every stop. It shifted great since I bought the wagon at 138,000 miles and looked like the transmission oil was never changed when I bought it. After many drain and fills with 3309 types of fluid over the years, I settled into a yearly drain and fill every summer. It absolutely shifted great.
Unfortunately, weighing the cost to rebuild the cylinder head and other possible future costs, I drove it to the scrap yard last spring.