Although I do not fully agree to not run low viscosity fluids, I am a fan on castrol imv in older vehicles.
1999 Toyota Avalon w/Low Mileage Trans Slips When Cold
- Thread starter edge10
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If it called for Dex III, why not use Dex VI which is backward compatible? Drain, refill, drive. Repeat 2 more times minimum. When the fluid on the dipstick looks like the fluid in the bottle, you're done.
I have owned many cars from 1999, 2000 era and still have one in my driveway (2000 Hyundai Sonata). All of them worked perfectly with the Castrol IMV and lasted about 200k miles. Heck, I used that even in Fords that were specified for Mercon V (when the Castrol Mercon V was missing from shelvs).
The newer spec fluids will just ask for trouble, for no real gains. They say it's "compatible" but that's just not true. Their viscosity is different and that's a fact.
The newer spec fluids will just ask for trouble, for no real gains. They say it's "compatible" but that's just not true. Their viscosity is different and that's a fact.
DEX VI is backward compatible for GM's, but is not necessarily right for older imports.
Just get plain old DEXRON III type fluid and service it. My guess is some of the seals due to age are no longer able to assist in maintaining pressure and going thinner (LV) is not going to help your cause. Hopefully @clinebarger chimes in because I'm not a transmission expert but he is.
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I'm Sure Dexron III is harder to get than Maxlife. I had a 98 Sienna which should be very similar. I used Maxlife and Mobil 1 ATF. Maxlife works like a champ. Get yourself a filter (aka strainer ) and replace that while you are at it. 21 years on the same fluid cannot be good regardless of the mileage.
AutoMechanic
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Change the fluid and filter if it has one I don’t know on these. I’d use Castrol Transmax that’s what I use in my Toyota stuff. No issues at all.
My lady's 98 Camry I did 3 drain and refills using Coastal DexMerc in it. It has been perfect.
I'd recommend using a Dexron III fluid in an older car like that Avalon or like my lady's 98 Camry.
Viscosity in my opinion is not the biggest concern... It is how the fluid is friction modified is what matters most. And those older Asian cars and trucks that took Dexron III in my opinion it would be best to just use a transmission fluid that is friction modified just like the fluid that went in them 20+ years ago.
I'd recommend using a Dexron III fluid in an older car like that Avalon or like my lady's 98 Camry.
Viscosity in my opinion is not the biggest concern... It is how the fluid is friction modified is what matters most. And those older Asian cars and trucks that took Dexron III in my opinion it would be best to just use a transmission fluid that is friction modified just like the fluid that went in them 20+ years ago.
That friction modifier action is reflected in the viscosity numbers.
Viscosity is the measurement of fluid's internal friction, can be conceptualized as quantifying the internal frictional force that arises between adjacent layers of fluid that are in relative motion:
Viscosity - Wikipedia
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4WD
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4WD
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As stated a hundred times here … Dex VI holds viscosity at temperature better than the old stuff. I’m not researching his stuff … I’m responding to others making the point that Dexron VI is backwards compatible
you can also compare to MaxLife viscosity
BTW: used to tow a 32’ park trailer with a 2500 GMC ~ would cook that old Dexron like bacon grease.
Most of us switched to Mobil 1 ATF back then … it’s still around
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No need for the holier than thou "Whatever..." on a transmission fluid post. There are tons of transmissions running factory fill dexron that has sheared well beyond the viscosity of the modern fluids along with exhausted the benefit of the additives that are still shift just fine. It is likely Dex VI will work just fine and more than likely longer than any of the traditional fluids. When you look at the service intervals for most older cars and the shearing of dex 3, you're pretty much just refreshing the fluid to dex vi starting viscosity to then be sheared down again.
Unfortunately you cannot buy a fluid with that specification anymore
It's even part of the DEXRON VI specification. And not only is it backwards compatible, it supersedes the previous license.
It would be similar to saying "Stick with SG rated 5W-30 oil, don't use the current SP 5W-30."
Decades ago I had a slipping 727 in a Dodge truck. I sucked out 1 qt and put Trans-X in it. It fixed it for the remainder of the time I had it. Year or so.
I'm not arguing that Dexron III is the best choice in this particular application, but I just don't buy the idea that you can't get functionally identical Dexron III anymore. It's not the branding on the bottle that makes it work, and it's obvious that Valvoline, Castrol, etc. that made the stuff for decades didn't forget how to make it just because they can't license the name anymore.
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not.even.close.
4WD
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Yeah, almost anything now has better base stock than the old Dexron III … exactly why many of us put Mobil 1 ATF in those older units …