Gentlemen,
I own a 2015 Hyundai Genesis (aka G80) 3.8L v6 with 8-speed automatic transmission. The car runs great except that it recently started to shift harsh from 4th to 5th gear. I looked it up in Genesis forums most opinions are about solenoids that may be the cause of this harsh shifting.
I just recently drained and filled the ATF fluid 3 times in row; still the issue persists and still does harsh shifting from 4th to 5th gear. I did not change the solenoids yet; no DTC codes in the OBD2 scanner either.
Hence my question: is there an ATF additive that I can add that may be able to clean the shift solenoids over time and helps with the shudder or harsh shifting? I primarily am looking for an additive that cleans the solenoids and not looking for something like Lucas Stop Slip or the like.
Your thoughts will be appreciated.
Thanks,
Husam
Shift Solenoids Cleaner additive?
- Thread starter Husam
- Start date
Lubegard products are well regarded for this purpose. Also, adding extra magnets to the pan to grab ferrous metal particles before they reach the solenoids is something else often suggested.
I'm not familiar with an additive cleaning a solenoid more effectively than just straight, new ATF. Even then, fluid's not going to do a lot to undo what's been done. An additive <span style="font-style: italic">may</span> mask the symptom, but it's not going to solve the problem.
I use lubegard red as preventative maintenance when I do atf changes. I'm running idemitsu hk in place of sp3 and I dose one ounce per quart of total transmission capacity. I see no harm in trying a bottle in your transmission. Even the resident chemist Mola said it may clean transmission internals. I've also had success in an impala with harsh 2-3 shifts, felt like a bucking horse and shifted smoothly after treatment and atf change.
Originally Posted by nobb
If the solenoids are already failing, doesn't it mean that there's too many magnetic particles surrounding it? If the particles are stuck to the magnets, I don't see how any additive could get it off.
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Thanks you gentlemen for your suggestions.
I already changed the ATF fluid three times in a row (drain and fill).
I will consider the following:
- Lubegard Red
- Seafoam transtune
if they do not solve the problem (though solenoid magnet may not get cleaned i guess); i will either manually get the solenoids cleaned or replaced.
Originally Posted by ripcord
Lubegard products are well regarded for this purpose. Also, adding extra magnets to the pan to grab ferrous metal particles before they reach the solenoids is something else often suggested.
The part number for lubegard red is 60902.
Originally Posted by Husam
Thanks you gentlemen for your suggestions.
I already changed the ATF fluid three times in a row (drain and fill).
I will consider the following:
- Lubegard Red
- Seafoam transtune
if they do not solve the problem (though solenoid magnet may not get cleaned i guess); i will either manually get the solenoids cleaned or replaced.
I'll preface this by saying I'm not familiar with this specific transmission.
But there are typically two levels of filtering upstream of the solenoids, the pump inlet filter and the individual "last chance" filter screens on the solenoids themselves. So you don't expect contamination unless something like a clutch plate de-lamination causes a LOT of debris.
If this unit has a removable oil pan, it's pretty easy to do a visual. Solenoids are typically retained in the control valve body by a bolt- on bracket, roll pins, or similar.
I already added Lubegard Red today, and I drove for about 50KM. I noticed a very slight improvement in the shift quality from 4th to 5th gear that used to be shifting harsh.
How long does it take for Lubegard to take full effect usually?
Thank you,
Husam
How long does it take for Lubegard to take full effect usually?
Thank you,
Husam
Over the next few hundred km you should notice smoother shifts. The manufacturer says you can add up to 2 ounces per liter of total fluid capacity. That would be the maximum treatment. Good luck and happy motoring.
Lubegard platinum....just put it into a mazda 6 speed.
Stuff is amazing. I normally use the lubegard red protectant but called lubegard and was advised to use the platinum product.
It is their newest trans fluid protectant.
No additive is going to dislodge a metallic particle once it has magnetically adhered to a solenoid.
## Status Update ##
Gentlemen,
2015 v6 3.8L RWD Genesis: Condition:
- Mileage = 92,500 Miles which is about 149,000 KM.
- Location: Dubai
- Warranty: Expired
- Car very well maintained, regularly.
- All fluids changed (Engine Oil, Radiator fluid, Brake Fluid, Diff Fluid)
- All filters changed.
- Transmission fluid completely drained and filled 3 times in a few days in the dealership with a new pan.
- Zero codes in scanner; system check: OK.
Situation:
- Hard shift or slam-like shift from 4th to 5th gear with more than gentle throttle applied. Hence I performed the above service.
- While pushing pedal with (let's say) 15% throttle, Hard Shift b/w 4th and 5th gear is very apparent.
- While changing throttle positions (i.e., very gentle acceleration, shifting is very smooth), or (i.e., more than 1/2 throttle, shifting is smooth too) between these two gears.
Action Taken:
- Transmission fluid completely drained and filled 3 times in a few days in the dealership with a new pan -- same issue persisted.
- Added a bottle of Lubegard Red into the ATF fluid -- same issue persisted.
Analysis:
- A bad shift solenoid that is clogged or dirty or got metallic particles in it.
- A bad throttle position sensor? (no codes in OBD scanner though)
- Speed sensor?
- Valve body?
What do you guys think the best course of action is? My last resort is to pay for a full Transmission replacement which I am trying to avoid by carefully eliminating the problem.
Let me know your thoughts.
Thanks,
Husam
