8-Speed Transmission Flush

[EdP]

There is a difference between going cheap and going smart. Oils are formulated with specific specs and you can be sure that Hyundai does not manufacture any fluids used in their vehicles. Hyundai also thinks we are stupid enough to believe that there exists a "lifetime" trans fluid. They are not the only vehicle manufacturer to subscribe to such labels. Call it what you want, like generic prescription meds you can get a safe fluid from other manufacturers and be smart to save a lot of hard earned cash. Valvoline MaxLife Full Synthetic trans fluid matches the factory spec fluid and guarantees it will be just fine and will not affect the vehicle warranty in writing. For $18/gallon, it is a win-win. As in many questions in life, there can be more than one right answer. Here is one such example. In my BMW 740il then with 105,000 miles on it I changed the lifetime trans fluid with proper spec Mobil 1 full syn fluid and ran it an additional 140,000 miles without issues.

Define "lifetime" in automotive life.
I would assume Hyundai did some testing and the fluid lasted to their lifetime, but that may differ from yours. Longest I ever kept a car was 182,000. Trans was still working fine but 2nd engine died.

 

[PMCErnie]

There is a difference between going cheap and going smart. Oils are formulated with specific specs and you can be sure that Hyundai does not manufacture any fluids used in their vehicles. Hyundai also thinks we are stupid enough to believe that there exists a "lifetime" trans fluid. They are not the only vehicle manufacturer to subscribe to such labels. Call it what you want, like generic prescription meds you can get a safe fluid from other manufacturers and be smart to save a lot of hard earned cash. Valvoline MaxLife Full Synthetic trans fluid matches the factory spec fluid and guarantees it will be just fine and will not affect the vehicle warranty in writing. For $18/gallon, it is a win-win. As in many questions in life, there can be more than one right answer. Here is one such example. In my BMW 740il then with 105,000 miles on it I changed the lifetime trans fluid with proper spec Mobil 1 full syn fluid and ran it an additional 140,000 miles without issues.

Why risk letting anyone other than your Hyundai/Genesis dealer do this job? If you muck it up elsewhere there goes your 10/100,000 warranty (poof!). If you have no warranty then by all means get it done anywhere you like since you are an expert.

 

[kw012]

Why risk letting anyone other than your Hyundai/Genesis dealer do this job? If you muck it up elsewhere there goes your 10/100,000 warranty (poof!). If you have no warranty then by all means get it done anywhere you like since you are an expert.

A trans flush is not complicated but a simple procedure. The dealer tells me they will flush with whatever fluid I want. A local indy, a BG service center will also do it for less. Truth is the scare tactics about "OEM" fluid being the Holy Grail is something I no longer will consider. Your engine has a decal on the air filter box with a brand of motor oil. Do you subscribe to that brand only? The power steering fluid has same in the owner's manual but the manual only tells us to inspect but no change interval is mentioned. I am ready to change the rear differential fluid with Amsoil. There are times when we have to make choices on our own when it comes to maintaining these systems. There can be multiple correct choices, some are better than others. Like pizza! lol

 

[princelybug]

I am ready to change the rear differential fluid with Amsoil.

Per the service manual, rear diff fluid should be changed every 80K mi (128K km), under "severe driving conditions."

 

[kw012]

Keith, do you know what the rear diff fluid spec is for us?

Sure! See attachment straight from the Hyundai maintenance data that came with the car. Also look over the transmission fluid section. It says to use Hyundai fluid OR other brands meeting the above specification set my Hyundai. Enough said about transmission fluids! I threw in the docs from Valvoline for a bonus.

 

[kw012]

Why risk letting anyone other than your Hyundai/Genesis dealer do this job? If you muck it up elsewhere there goes your 10/100,000 warranty (poof!). If you have no warranty then by all means get it done anywhere you like since you are an expert.

Not sure if you are still following my thread, so I thought to share this in case. Hyundai says other brands OK in their documentation if it meets their specs. Good stuff. Threw in the Valvoline doc for good measure.

 

[kw012]

Define "lifetime" in automotive life.
I would assume Hyundai did some testing and the fluid lasted to their lifetime, but that may differ from yours. Longest I ever kept a car was 182,000. Trans was still working fine but 2nd engine died.

Hey Ed- Here are the supporting docs about other brand trans fluids from Hyundai. Threw in Valvoline spec sheet too. Hyundai endorses other brands that meet their specs.

 

[princelybug]

Rear differential fluid:

Hypoid gear oil API GL-5, SAE 75W-90 (Shell Spirax X equivalent)

Anyone have a Hyundai part number for this fluid?

 

[PMCErnie]

My point is simple. Few vehicles have a 10/100,000 powertrain warranty. As long as I have that coverage in effect I’ll use a Hyundai dealer to service my powertrain.

 

[EdP]

Hey Ed- Here are the supporting docs about other brand trans fluids from Hyundai. Threw in Valvoline spec sheet too. Hyundai endorses other brands that meet their specs.

Good to know what works.

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[kw012]

Rear differential fluid:

Hypoid gear oil API GL-5, SAE 75W-90 (Shell Spirax X equivalent)

Anyone have a Hyundai part number for this fluid?

I want to know what size and type of socket/wrench is required for the drain and fill plugs for the differential.

 

[Hugh185]

Even though Hyundai claims it is a "lifetime transmission fluid" - you'd be best served to change it out anyway as there is no such thing. ALL lubricant - no matter how heavy duty it is - breaks down, loses viscosity and suffers from the effects of heat. Hyundai says "lifetime" because to them a lifetime is 100k - the length of the powertrain warranty. Even that is pushing it, honestly.

I wouldn't run it more than 50k before doing so. Unfortunately without a complete trans removal you can only do 5 of 11 quarts at a time. "Draining" - and even dropping the pan does not empty out the whole system - including the valves, gear train and torque converter. For that - I'd recommend you change it 3 times. Drain & fill 5 qts, drive for an hour, drain and fill again, drive, drain and fill. Make sure the car is level (jack stands up front, floor jack on the rear diff in the back). Will cost you about $100 in fluid and 5 hours of your time - but you only need 2 wrenches, a screwdriver and a drain pan to do it. Better than having a dealer replacing your trans if you don't need it (yet).



This. Thank you If folks take care of their Gennys they will last well past the "lifetime" that Hyundai expects them to.

Totally agree the ATF has to be changed, there are tons of friction and condensation. On a Porsche Cayman there are 8 magnets to catch the steel particles generated by the friction between the moving parts. And guess what after 50k miles the magnet are covered and inoperative. So yes the ATF change is really important, vital