UOA Maxlife & Dex III | 98 V70 186k | 14.5k OCI

[VeryNoisyPoet]

Just got the analysis on my ATF from the car in my sig. Here's a quick history:

Winter of 2016 at around 168k miles it got the first drain and fill it had seen in a while. Fluid was brown, stinky, and overdue. I didn't sample at the time...and I'd be somewhat afraid to see how bad it was. Decent amount of fuzz on magnet but all super fine sludge with no chunks. Fluid didn't feel noticeably gritty and didn't show any "glitter" in the drain pan. No filter to change - just a permanent internal rock catcher screen. I put in 3.5 quarts of Pennzoil generic Dex/Merc. Greatly reduced harsh shifting, but did not eliminate it.

Summer of 2017 at around 172k miles it got two more D&F. First with generic Dex/Merc, and the second with Valvoline Maxlife and red bottle Lubegard. Fluid came out dark red-brown but didn't smell as bad, had no gritty feeling, and magnet had only a small layer of fine sludge. I added a transmission temperature gauge at the hot line to the cooler to keep an eye on it since I knew I was in for some hard, hot miles.

I then took it on a road trip to the west coast and back and drove it all fall and winter for my commute. Shifting really smoothed out over time until it was shifting like new. Max temp I saw on the gauge was 115C /239 F, but only for a minute before I downshifted to let it cool off. Temps generally ran between 75C / 167F and 100C / 212F.

At the beginning of the month at 186,600 miles I did another D&F with Maxlife when I rebuilt the cooler lines and added an external cooler. That's when I took a sample with about 14.5k miles on the fluid. Fluid was dull red, felt slippery, and smelled just like the fresh Maxlife (you'll know what I mean if you used that stuff). Small amount of fine sludge on magnet, with no chunks.

I'm hoping the high iron, aluminum, and insolubles are biased up from 10-15% of the really old fluid that remained after the three D&F, and from cleaning action of the new fluid picking up deposits. I'll be doing a another drain and fill in a few hundred miles, which should have all but a couple percent of the old fluid removed. Next year I'll sample it again, which will probably be close to their recommended 15k miles.

 

[SirTanon]

Obviously I can't say for certain, but based on your story, I'd say the likelihood is good that the high metal numbers are left over largely from the remainder of the fluid's neglect up through 168k miles, as well as a good likelihood that the newer fluid was able to collect some of the built-up gunk from inside the transmission.

FWIW, I do regular drain & fills on the 6F35 trans on my Fusion every 20-30k miles, and my numbers for wear metals are (somewhat) comparable. Granted, we don't have the same trans, but I suspect most transmissions wear somewhat similarly when it comes to wear metals showing in a UOA. I'd run it some more, and then get a UOA done on your next drain & fill. I bet the numbers are lower.

For comparison, here is my latest UOA from my trans: 6F35 Trans UOA - 223,968 miles

 

[VeryNoisyPoet]

Thanks for the input. Your report looks good, so I wish you many more trouble-free miles.

The harsh shifting was certainly caused in part by lazy gummed up valves, so there's probably a fair bit of crud that got flushed out this past run. Slam shifting improved immediately when fluid was changed, then the remainder of the issues faded over many thousand miles as things got cleaned up.

The next drain and fill is coming up real soon because I want to get the last of the generic Dex/Merc out and more Maxlife in, but I'll sample again next year when there's been enough time for any trends to develop. Everything feels really good so far, so fingers crossed.

 

[zeng]

Temperature to factory cooler at 85-100*C appears on the high side for components protection, I opined.
It's a good move of OP installing an external cooler to bring peak temperature down, hopefully to 80-85*C and below.
Anyway I would seriously consider an ATF+4 for this application. JMHO.

 

[VeryNoisyPoet]

With transmission cooler, operating temps now generally run between 70C and 90C. I installed a thermostat to bypass the external cooler until fluid warms up, since I can feel the drag when the fluid is cold. Also used my custom temp gauge to command the radiator fan to start when the ATF hits 90C, which drops it right back down.

Are transmissions really so fragile? I see some sources that claim that one needs to run their ATF so cool that they lose fuel economy, or else their transmission will die early. Others give a more reasonable range of between 70C and 105C.

Out of curiosity, what advantage would ATF+4 have in this application?
For example, Valvoline's PI sheets claims their ATF+4 is semi-synthetic and formulated just for Chrysler transmissions, with no mention of compatibility or testing for other applications. Their Maxlife says full synthetic, has beefed up add pack for older transmissions, and meets the Dex III (original spec) plus Dex 6 and JWS-3309 (current spec) that my transmission calls for.

 

[dave1251]

Originally Posted by VeryNoisyPoet
With transmission cooler, operating temps now generally run between 70C and 90C. I installed a thermostat to bypass the external cooler until fluid warms up, since I can feel the drag when the fluid is cold. Also used my custom temp gauge to command the radiator fan to start when the ATF hits 90C, which drops it right back down.

Are transmissions really so fragile? I see some sources that claim that one needs to run their ATF so cool that they lose fuel economy, or else their transmission will die early. Others give a more reasonable range of between 70C and 105C.

Out of curiosity, what advantage would ATF+4 have in this application?
For example, Valvoline's PI sheets claims their ATF+4 is semi-synthetic and formulated just for Chrysler transmissions, with no mention of compatibility or testing for other applications. Their Maxlife says full synthetic, has beefed up add pack for older transmissions, and meets the Dex III (original spec) plus Dex 6 and JWS-3309 (current spec) that my transmission calls for.



The ATF+4 suggestion is not an informed opinion in my view. How is the transmission doing now?

 

[zeng]

Originally Posted by VeryNoisyPoet
With transmission cooler, operating temps now generally run between 70C and 90C. I installed a thermostat to bypass the external cooler until fluid warms up, since I can feel the drag when the fluid is cold. Also used my custom temp gauge to command the radiator fan to start when the ATF hits 90C, which drops it right back down.

Are transmissions really so fragile? I see some sources that claim that one needs to run their ATF so cool that they lose fuel economy, or else their transmission will die early. Others give a more reasonable range of between 70C and 105C.

Out of curiosity, what advantage would ATF+4 have in this application?
For example, Valvoline's PI sheets claims their ATF+4 is semi-synthetic and formulated just for Chrysler transmissions, with no mention of compatibility or testing for other applications. Their Maxlife says full synthetic, has beefed up add pack for older transmissions, and meets the Dex III (original spec) plus Dex 6 and JWS-3309 (current spec) that my transmission calls for.

Reference to Wizman chart Valvoline ATF+4 vs Dex/Merc below:

Valvoline ATF Dex/Merc at 90*C would have an operating viscosity of 7.2 cSt.
Valvoline ATF+4 at 90*C would have a whopping 28% thicker operating viscosity of 9.2 cSt , potentially reducing boundary/mixed lubrication regimes tremendously and components wear.

Looking from another perspective at similar level of operating viscoisty of say 5.9 cSt for both fluids , fully synthetic Valvoline ATF+4 (it is not blend) at 115*C has a 15*C additional margin over and above that of Valvoline Dex/Merc 's 100*C ..... hence it's no brainer in extra components protections benefits from ATF+4 IMO should you select so.

 

[dave1251]

Originally Posted by zeng
Originally Posted by VeryNoisyPoet
With transmission cooler, operating temps now generally run between 70C and 90C. I installed a thermostat to bypass the external cooler until fluid warms up, since I can feel the drag when the fluid is cold. Also used my custom temp gauge to command the radiator fan to start when the ATF hits 90C, which drops it right back down.

Are transmissions really so fragile? I see some sources that claim that one needs to run their ATF so cool that they lose fuel economy, or else their transmission will die early. Others give a more reasonable range of between 70C and 105C.

Out of curiosity, what advantage would ATF+4 have in this application?
For example, Valvoline's PI sheets claims their ATF+4 is semi-synthetic and formulated just for Chrysler transmissions, with no mention of compatibility or testing for other applications. Their Maxlife says full synthetic, has beefed up add pack for older transmissions, and meets the Dex III (original spec) plus Dex 6 and JWS-3309 (current spec) that my transmission calls for.

Reference to Wizman chart Valvoline ATF+4 vs Dex/Merc below:

Valvoline ATF Dex/Merc at 90*C would have an operating viscosity of 7.2 cSt.
Valvoline ATF+4 at 90*C would have a whopping 28% thicker operating viscosity of 9.2 cSt , potentially reducing boundary/mixed lubrication regimes tremendously and components wear.

Looking from another perspective at similar level of operating viscoisty of say 5.9 cSt for both fluids , fully synthetic Valvoline ATF+4 (it is not blend) at 115*C has a 15*C additional margin over and above that of Valvoline Dex/Merc 's 100*C ..... hence it's no brainer in extra components protections benefits from ATF+4 IMO should you select so.



The static and dynamic friction coefficients of the ATF+4 and Dexron are not the same.

 

[zeng]

Originally Posted by dave1251
Originally Posted by zeng
Originally Posted by VeryNoisyPoet
With transmission cooler, operating temps now generally run between 70C and 90C. I installed a thermostat to bypass the external cooler until fluid warms up, since I can feel the drag when the fluid is cold. Also used my custom temp gauge to command the radiator fan to start when the ATF hits 90C, which drops it right back down.

Are transmissions really so fragile? I see some sources that claim that one needs to run their ATF so cool that they lose fuel economy, or else their transmission will die early. Others give a more reasonable range of between 70C and 105C.

Out of curiosity, what advantage would ATF+4 have in this application?
For example, Valvoline's PI sheets claims their ATF+4 is semi-synthetic and formulated just for Chrysler transmissions, with no mention of compatibility or testing for other applications. Their Maxlife says full synthetic, has beefed up add pack for older transmissions, and meets the Dex III (original spec) plus Dex 6 and JWS-3309 (current spec) that my transmission calls for.

Reference to Wizman chart Valvoline ATF+4 vs Dex/Merc below:

Valvoline ATF Dex/Merc at 90*C would have an operating viscosity of 7.2 cSt.
Valvoline ATF+4 at 90*C would have a whopping 28% thicker operating viscosity of 9.2 cSt , potentially reducing boundary/mixed lubrication regimes tremendously and components wear.

Looking from another perspective at similar level of operating viscoisty of say 5.9 cSt for both fluids , fully synthetic Valvoline ATF+4 (it is not blend) at 115*C has a 15*C additional margin over and above that of Valvoline Dex/Merc 's 100*C ..... hence it's no brainer in extra components protections benefits from ATF+4 IMO should you select so.



The static and dynamic friction coefficients of the ATF+4 and Dexron are not the same.

Numerically ? Yes,marginal and insignificant delta if any. But that doesn't change the general position.
Btw, static CoF is irrelevant in OP's context .

 

[dave1251]

Your right it doesn't matter a transmission designed and built before ATF+4 was around will perform better with ATF+4 which is not in the same family as the recommended DEXRON.

 

[MolaKule]

This so-called Wizman chart, is the viscosity calculated using some general formula or is this a result of actual testing at temp?

Valvoline uses temp and shear stable VII in the final additive package for the finished lubricant, so I have trouble accepting that the MaxLife ATF viscosity drops to less than 5.0 cSt at the higher temps.

BTW, ATF+4 has different static and dynamic coefficients of friction than does the Dexron III/Merc fluid and the delta is not insignificant.