Transmission Fluid Help

Speedbowl14

Speedbowl14

Ryan Preece and short tracks
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I have a car...a 2010 Hyundai Elantra (typically the smallest car you'll see at a racetrack, lol). I bought it with 73k miles, it's up to 83k now. I had incorrectly assumed the transmission fluid had been changed sometime in the vehicle's life. Based on the fluid I saw today...it hasn't. The manual says it should be changed ever 60k miles. The fluid is not black, and does not have any odor to it (no burning or metal pieces). It is very very brown, no red left in it. I took it to the local shop who said they wouldn't touch it because of how far away from the 60k mile benchmark it was. I took it to the transmission shop. They said they'd change out the fluid but told me I should consider just leaving what's in there.

From my minimal car knowledge/research...a flush is out-of-the-question. Am I better off leaving what's in there in there, or should they drop the pan, replace the filter, and put new fluid in? The tranny shop manager said he'd be able to get about 3/4 of the current fluid out.

If this helps...the car is a bit "clunky" in the mornings. I've experienced some slippage trying to beat red lights (some, as in maybe three times in the 10k miles I've driven the car). However with the cold weather I've had trouble going into reverse twice now. It will go in reverse but the throttle will not catch, and revs like I'm in neutral. This lasts 3-5 seconds before it gets into gear.

Any help is gladly appreciated!
 
Mine is a 12 elantra. I haven't even hit 60K yet (bought it at 30 or 40).

That sounds more like an electrical/solenoid issue than hydraulic. Very few newer transmissions are hydraulically/line pressure activated. Most have electronic solenoids that route the fluid to the different clutch/band application ports. Might also be that it is volumetrically low on fluid and not being picked up by the front pump as quickly (some newer transmissions use a clutch activated front pump instead of being driven by the torque converter, and the pump clutch is disengaged in Park and Neutral).

Hydraulically, being "only" 20K over service, I would go ahead and replace the fluid and filter. If it's just brown and not black/burned, it hasn't gotten hot enough to break down. It's not like an engine where thin fluid will get through tolerances that thick fluid won't. There's not really any tolerance restrictions in a transmission, it's more of the pump shoving fluid through the applicator bands and clutches. I wouldn't see any ill issues to having the fluid changed.
 
Is the filter fiber or simply a screen? It isn't going to hurt to drop the pan and replace the filter. Does the torque converter have a drain plug? If so, drain the converter at the same time that you pull the pan to replace the filter.
Do you know the history on the car? Has it been overheated?
 
Local shop wouldn't touch it? Why do they care if it's past due for new fluid? All the more reason for them to service it ASAP. Sounds like they missed out on a potential sale.

Trans shop said to leave it how it is? What was their reasoning? Sounds like they want the trans to go to **** sooner so they can make a killing when you have them rebuild it.

Like mentioned above, definitely replace the fluid and filter. IMO that's by far the smartest choice.
 
2 Sweet said:
Local shop wouldn't touch it? Why do they care if it's past due for new fluid?
Click to expand...

Maybe they know of Hyundai trans issues with and don't need the hassle of a customer returning a month later screaming "IT WAS OK UNTIL YOU WORKED ON IT!!!!"

BTDT

I stood there and watched a guy berate my friend because the paint didn't match. He wanted several hundred off the bill. Guy was on full rant mode and >< this close to popping a vein in his head. Ernie just stood there until the guy ran out of breath. Then Ernie calmly pointed out that wasn't the side of the car he fixed... LMFAO!!!
 
Generally, a faulty transmission solenoid will throw a code and cause the check engine light to come on. Your local auto parts store should be able to pull codes for free.
 
Trans shop said they'd only be able to get out 3/4 of the fluid? Try another shop. I can get that much out without any special equipment. But that's not what he's talking about.

Inside the trans, you have 'clutch packs'. A sandwich of steel plates and rings of what are essentially round brake pads. All immersed in lubricant. When a gear engages, these are slammed together hydraulically, overcoming the lubricant and moving your car. When not in gear (first, third or fourth when you're in second) the hydraulic pressure is removed, but they're still in contact .. just like your front disk brake pads. Over time, those rings (termed friction material) do wear. The worn 'brake dust' is suspended in the fluid, and supposed to be caught in the filter ... but the filter isn't that good. A lot stays in suspension. Changing the fluid and filter removes that grit.

Here's the thing. That same grit is wearing away at bearings and gear surfaces ... but is also helping the clutch packs grip as they wear out. As more and more grit builds up in suspension, a lot starts to fall out of suspension. Some into the pan, some into all the nooks and crannies all over the trans. That's what he can't get out. It's also causing your clutch surfaces to wear faster too. Many transmission shops have been bitten when they did a fluid flush and suddenly there wasn't enough grip to prevent slippage of the clutches, requiring a rebuild, and accusation by the client that it worked fine before they touched it. Also most automatics today are electrically controlled. The solenoids that engage and release clutch packs are also susceptible to failure thanks to all that suspended grit. All told, it's a lose lose situation for any mechanic.



You, on the other hand, my dear original poster .... warrant a good hard kick in the seat of the pants.You're the sort of person who ruins my morning commute. At least once a week, you should be checking all the fluids. IF it's a fluid you can't check yourself easily, you get it checked when you get your oil changed. My wife's 2005 Malibu doesn't even have a transmission dipstick ... but it has fill holes. Pulling the bolt when the mechanic has it on the lift takes seconds .. they don't even charge me for it. You weren't given the receipt for a scheduled maintenance repair when you bought the car. Anyone who does 'scheduled maintenance' keeps the receipts. Always. This fluid didn't suddenly turn brown overnight. You weren't checking it. You should have caught this months ago. Hell. your should have caught it the day you bought the car. I have no sympathy.
 
Btw, I don't know about Hyundai but now there's quite a variety of manufacturer specific trans fluid. Use of the wrong fluid can cause significant damage
 
2 Sweet said:
Local shop wouldn't touch it? Why do they care if it's past due for new fluid? All the more reason for them to service it ASAP. Sounds like they missed out on a potential sale.

Trans shop said to leave it how it is? What was their reasoning? Sounds like they want the trans to go to sh!t sooner so they can make a killing when you have them rebuild it.

Like mentioned above, definitely replace the fluid and filter. IMO that's by far the smartest choice.
Click to expand...

The local shop said they would drain/replace, but not flush.

As @Professur said the current fluid has pieces of the transmission that give it the friction it needs. Change it out and there's a risk of there being too little friction (from my understanding) causing gear slipping. Keeping it in keeps the friction, but risks gunking up the transmission. I'm not really sure what's best.
 
BobbyFord said:
I'm not familiar with Hyundai auto trans but a quick internet search reveals that they are prone to auto trans issues...

http://www.carcomplaints.com/Hyundai/Elantra/2010/transmission/transmission_slipping.shtml

http://www.carcomplaints.com/Hyundai/Elantra/2010/drivetrain/power_train.shtml
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Yep, I had a 2002 Sonata with a similar issue, and I wasn't sure what to do about it either. I'm not a mechanic, and I was told that replacing the transmission fluid might mess it up even more. It had over 140K miles on it, so I ended up just trading it and my dad's car (which I was on the hook for) in for my Corolla.
 
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