The two best ATF’s I’ve run in my wife’s 6F35 Fusion were Castrol & Amsoil. Mercon LV doesn’t seem to last very long in this transmission.
Havoline Multicar full synthetic is also a licensed Mercon LV fluid but I haven’t tried that one yet.
post your latest transmission lubricant change.
- Thread starter ledslinger
- Start date
Havoline Multicar full synthetic is also a licensed Mercon LV fluid but I haven’t tried that one yet.
Yes I drove it for about 15 mi afterwards and feels very good. Smooth up shifts and downshifts
Thank you for that.
The Pennzoil was less expensive than the Castrol, it was a toss up so I went Pennzoil this time. The Pennzoil has a Mercon LV license so we'll see how it goes.
I was thinking of trying the Amsoil, but I wanted to make sure this was a fluid issue first. Amsoil is more than double the price of the Pennzoil in Canada.
Havoline isn't readily available up here. Walmart has the SuperTech that is a licensed Mercon LV. It was even cheaper than the Pennzoil.
There was no perceptible difference in shift quality between Castrol & Amsoil in my wifes car. Amsoil lasts longer before the 2-3 shift begins to get a tad jerky again, that's all. I don't live in a very cold climate but I'd guess that's where you'll likely see the largest difference (prior to the oil coming up to temperature).
A local Chevron distributor to me had a 6 gallon pit pack of the Havoline fluid a while back for around $165. I nearly jumped on it to try but didn't. When I went back it was gone & I just stayed the course with my usual Amsoil SS transmission fluid as it's always had solid results for me. The Havoline seems to be very close to the Castrol in specs.
BrendanC
$100 site donor 2024
2018 silverado 2500HD 6.0L/6l90 112k
out/off: factory fill and factory filter.
in/on: carquest premium filter with 7.5ish quarts Valvoline Dexron VI and Lubeguard red.
old fluid was still perfect cherry red and literally just a light dusting on the magnet. this truck grosses about 8600lbs at all times and is in fleet service. i couldn’t believe it.
2018 silverado 1500 5.3L/6l80 148k miles
out/off: factory fill and factory filter
in/on: carquest premium filter with 7.5ish quarts of Fram Dexron VI with lubeguard red
old fluid was black and magnet covered. truck was hesitating and popping into gears. after fluid change with lubeguard it’s factory smooth again. really wish GM would’ve fixed the TC on the 80.
out/off: factory fill and factory filter.
in/on: carquest premium filter with 7.5ish quarts Valvoline Dexron VI and Lubeguard red.
old fluid was still perfect cherry red and literally just a light dusting on the magnet. this truck grosses about 8600lbs at all times and is in fleet service. i couldn’t believe it.
2018 silverado 1500 5.3L/6l80 148k miles
out/off: factory fill and factory filter
in/on: carquest premium filter with 7.5ish quarts of Fram Dexron VI with lubeguard red
old fluid was black and magnet covered. truck was hesitating and popping into gears. after fluid change with lubeguard it’s factory smooth again. really wish GM would’ve fixed the TC on the 80.
So far, it shifts and drives WAY better than it ever did on the Motorcraft Mercon LV, even when new.
Now that I have done it once myself, I wouldn't hesitate to do it myself again. Maybe next spring I'll give the Amsoil a try. I called the Ford dealer and they want $400 to do a 10 quart flush. It was $225 three years ago.
My daughters friend has a 2016 Escape and they just put a new tranny in at 180K KM. Almost $7K Canadian. So a couple hundred bucks in fluid is chump change compared to a new tranny.
Our Escape only has 91K KM on it. Seems the biggest issue with the 6F35 is lack of ATF changes. Fords "lifetime" fluid is an absolute joke.
The Amsoil is $184.80 for 2.5 gallon jug of the Signature Series. I paid $9.32/quart for the Pennzoil.
Did you use the Amsoil SS or the OE?
HPL Green ATF is another option. It works out to just over $100 Canadian a gallon by the time it gets shipped up here. Might last twice as long as any of the other options though.
Lifetime fluids are only meant to last the lifetime of the warranty. IMO the idea of a lifetime fluid (ATF or others) is just silly. Anyhow, a good way to extend the life of ATF is to keep it cool. My vehicle runs the OEM ATF cooler and two auxiliary ATF coolers. So far, so good.
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My commuter car is a 2021 Chevy Equinox with a 6T40 6-speed. The manual says 45,000 miles for severe service fluid changes, but I do it once per year (just under 30k miles). Apparently, GM says NOT to do the power flush, so I do two drain-and-fills...a few hundred miles apart. It's an easy job and keeps the fluid clear.
I have used Valvoline full synthetic Dex VI and AC Delco brand full synthetic Dex VI. The AC fluid provides noticeably smoother shifts.
I have used Valvoline full synthetic Dex VI and AC Delco brand full synthetic Dex VI. The AC fluid provides noticeably smoother shifts.
I've only used the SS Fuel Efficient ATF from Amsoil never the OE version. I've also been eyeing the HPL Green but I've had great results with the Amsoil in multiple vehicles so will likely continue with it. Shipping for HPL to me kills any savings over Amsoil for the 5 gallon buckets vs the 2.5 gallon two pack with Amsoil.
Recently acquired 2007 Impala. 3.5v6, 48k miles, 4T65E.
Installed a Transgo shift kit to remedy a very hard 1-2 shift when hot (known accumulator spring issue). New Dorman pan w/ drain plug, old one was rusty. New AcDelco pan filter. New AcDelco pan gasket. New Magnefine filter in the cooler return line.
New Amsoil SS (FE Blue Cap) ATF.
All done last week. Shifting 1-2 & 2-3 much improved, and smooth.
Installed a Transgo shift kit to remedy a very hard 1-2 shift when hot (known accumulator spring issue). New Dorman pan w/ drain plug, old one was rusty. New AcDelco pan filter. New AcDelco pan gasket. New Magnefine filter in the cooler return line.
New Amsoil SS (FE Blue Cap) ATF.
All done last week. Shifting 1-2 & 2-3 much improved, and smooth.
dnewton3
Staff member
That graph is likely based on the really old fluids such as Dex IIIH and Mercon, etc. Those are no longer licensed fluids; haven't been for maybe two decades now. The chart itself really tells us nothing substantially credible; what's the basis of the use of the word "failure", etc ... It's likely a reference to the viscosity breakdown that occurs with heat in those old fluids. It doesn't even identify what applications are in play, what fluids are used, etc.
Today's lubes (group III and up) are much better at sustaining heat. I doubt that graph is applicable now.
Many newer transmissions also have a thermostat. You can run a aux cooler but if the t-stat isn't opening until 200F not going to do much good anyway.
This chart is not accurate or applicable to a lot of modern ATF fluids. It dates back to when Dexron III and Mercon were what everyone used. Dexron VI and Mercon LV are designed to run all the time at ~220f.
The graph was published in 2024, but I do question the bona fides of the author of the article it was attached to. Notwithstanding, it's still very relevant insomuch as it correctly notes that heat is the number one killer of automatic transmissions. Also, irrespective of modern ATF's and any claim that they are designed to run hotter than older fluids, keeping the newer fluids cooler will still increase their useful life.
BrendanC
$100 site donor 2024
i still prefer to keep transmissions under 200°F. i have auxiliary coolers on both accords and they run about 170°. my truck has just a tru-cool 40k with the radiator bypassed. it will fluctuate between 150 and 200°F depending on how hard i’m driving it.
Modern cars have transmission fluid thermostats that prevent them from being cooled below their value. Adding a big aftermarket cooler just means that the thermostat has to open and close more frequently in normal operation. Additional cooling only helps when towing heavy.
There's many other circumstances that warrant additional ATF cooling other than towing. For example, driving in sport mode with the convertor lock-up disabled, driving into a head wind, racing, driving in soft sand etc. It's also possible (and sometimes recommended) to remove the ATF thermostat and allow cooling at all times. Anyhow, as I previously mentioned, I run 3 ATF coolers. Therefore, my ATF never exceeds 65 deg C (~150 deg F) and I'm pretty happy about that. YMMV.
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2017 BMW 530i
ZF8
VALVOLINE MAXLIFE BABY
URO FINNED ALUMINIUM PAN WITH REPLACEABLE FILTER.
ZF8
VALVOLINE MAXLIFE BABY
URO FINNED ALUMINIUM PAN WITH REPLACEABLE FILTER.
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Mechanic had not seen these before, he was really impressed. He was also really happy to use Maxlife, this is a full on race shop.
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