Overfilled ATF w/ Lucas Trans Fix
- Thread starter Wardonkey
- Start date
Was the transmission already full of fluid when you added the 24 oz?
What kind of transmission is it?
Some transmissions are prone to acting up when overfilled, much like they would when under filled.
You’re best bet is to drain out however much fluid you need to in order to get the fluid level back to full.
What kind of transmission is it?
Some transmissions are prone to acting up when overfilled, much like they would when under filled.
You’re best bet is to drain out however much fluid you need to in order to get the fluid level back to full.
Funny thing is... its running better now. Not slipping.
It was light pink. Not burnt at all.
That's odd. what make model year and mileage and when was the last service done.
2010 Buick Lucern with 98k. ATF was changed around 70K. Why is it odd the fluid isnt burnt? I added the Lucas because its hard shifting on rare occasions which i think is a solonoid issue.
So was it hard shifting or slipping? Because those aren’t exactly the same thing.
CleanSump
Site Donor 2026
On other sites you'd get OMG the world is ending, your transmission fluid is going aerate in the gears, overheat, blowout the breather, and blow up.
Reality is you probably would never notice if you didn't already know.
Reality is you probably would never notice if you didn't already know.
The reason nothing is stated is that it's common sense. Myself , I would never use Lucas. It's in there now so I would remove the excess otherwise the fluid could start to foam up maybe to the point of exiting out the breather at the top of the transmission. Foamy fluid doesn't work very well.
It hard shifting. Not very often, but ill take off from a dead stop and when it changes to the next gear it hard shifts. Once in a great while it did it so hard I thought I had gotten rear-ended.
Yes, remove some and bring the fluid to the proper level.
Probably would have been better off with a Lubegard product. Those at least aren't as snake-oily as Lucas.
lucas is good in 4t65-e transmissions in my experience. it coats more than it floats so if you suck fluid out of the dipstick tube you will probably get 98% atf, 1% lucas and 1% particles.
theres a tsb for the magnets in most 4t65-e transmissions. not sure if 2010 lucerne is included, but i bet it is. personally i would drop that pan asap to verify that yours has two donut magnets and not the one undersized and underpowered oem rectangle fridge-style magnet. the 2nd donut magnet goes on the filter in a certain spot. check the tsb. the new magnets increase magnetic power and surface area about 10X each...
the oem fridge magnet fills up quickly and the solenoids get caked in ferrous particles since theyre slightly magnetic. hard shifts are the result of the caked up solenoids. the solenoids are likely not worth swapping out because of the labor. i flushed one 4t65e 3x and it still shifts hard/full pressure only. we exclusively haul heavy stuff with that vehicle since thats what it insists on doing and its actually completely pleasant when its loaded up heavy or towing. but if its unloaded its annoying how hard it shifts.
it may get the 'valvoline restore and protect atf' next time. i doubt it has the ability to dislodge ferrous particles from slightly magnetic solenoids but it might be worth trying based on the marketing hype...
the magnets should be a recall not just a tsb in my opinion.
the delco donut mags are identical to the ones at home depot in the hardware aisle for a fraction of the price.
theres a tsb for the magnets in most 4t65-e transmissions. not sure if 2010 lucerne is included, but i bet it is. personally i would drop that pan asap to verify that yours has two donut magnets and not the one undersized and underpowered oem rectangle fridge-style magnet. the 2nd donut magnet goes on the filter in a certain spot. check the tsb. the new magnets increase magnetic power and surface area about 10X each...
the oem fridge magnet fills up quickly and the solenoids get caked in ferrous particles since theyre slightly magnetic. hard shifts are the result of the caked up solenoids. the solenoids are likely not worth swapping out because of the labor. i flushed one 4t65e 3x and it still shifts hard/full pressure only. we exclusively haul heavy stuff with that vehicle since thats what it insists on doing and its actually completely pleasant when its loaded up heavy or towing. but if its unloaded its annoying how hard it shifts.
it may get the 'valvoline restore and protect atf' next time. i doubt it has the ability to dislodge ferrous particles from slightly magnetic solenoids but it might be worth trying based on the marketing hype...
the magnets should be a recall not just a tsb in my opinion.
the delco donut mags are identical to the ones at home depot in the hardware aisle for a fraction of the price.
Actually, I sucked out a quart of ATF the day after I put the Lucas in. Now its at the full mark and not over. What I will say is that since putting in the Lucas, it has not hard shifted once. But with that said, I need to drive it a bit longer to verify this.
CleanSump
Site Donor 2026
Much as I dislike Lucas's version of Motor Honey, I did use the transmission additive once in an old Cherokee and it cured the bang and late shifts. Since have discovered Lubegard and put it in everything.
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