tranny fluid burned up after change

[confused]

I had the most confusing and scary experience ...

Volvo XC90 T6 with GM's 4T65E transmission, probably beefed up by Volvo or GM to handle the high torque of this engine. Owner's manual specs Dexron III for this transmission. 50K miles on the odo.

Did a routine pan drop and filter change and fluid top-off, using 7 qts Castrol Syntec ATF Dexron III/Mercon. 700 miles later realized that torque converter must be slipping because truck took excess RPMs to get it going so checked ATF and found that it had turned brown. Dropped pan again and no grit in the burnt ATF so hopefully clutches have not burnt and so hoping that all slipping was fluid shear in the TC. Dropped pan, refilled with dino Dexron III and drove truck and repeated 3 times to get a 90% or better fluid flush.

I put another 600 miles or so on truck since the flush and all seems OK now. Normal power and fuel economy and perfect smooth shifting and TC lockup. Fluid remains good and red.

Anyone have ideas on what could have gone wrong and what permanant damage or shortened life could result from this?

 

[confused]

I should add that the first time with the Castrol, I just dropped pan and replaced the 7 quarts that came out that way, rather than flushing the whole system.

 

[MolaKule]

It is good you saw no observable clutch material but I can tell you if a used oil analysis is done there will be plenty of insolubles of microscopic clutch material.


I would change again in < 10K with the new GM DexronIII-H or and go with Schaeffer's or Amsoil synthetic ATF.

 

[confused]

Any ideas about why this might have happened? And does anyone know that if clutches have started to slip, will they then continue to slip until burnt up - or has the damage been limited to what has already occurred? There was never a "service transmission" error message on the dash, but the vehicle is capable of displaying such messages. Thanks.

 

[Ken2]

The brand of Dexron-III ATF should not matter.

I'd do an Auto-Rx cleaning of the transmission then use a full synthetic ATF. I also like to install an in-line transmission filter http://www.ipdusa.com/ProductsCat.aspx?CategoryID=386&NodeID=275&RootID=629 (you can probably find one locally at an auto parts store for about $24.)

You might post your question on http://www.volvospeed.com/vs_forum/index.php They aren't lubricant experts, but the moderator is a Volvo tech with lots of experience.


Ken

 

[unDummy]

Even brown fluid should work. Something else is wrong.

You didn't state if you accurately checked the ATF level after the initial pandrop/refill following the owners manual's method which is?
What are the capacities listed in the manual?
Was 7 quarts sufficient or seriously overfilled?

Also, with 50k on the original fluid(?), there might have been some cleaning which is common in transmissions that don't have regular maintenance. Get a drainplug installed in that pan and practice more frequent drain/refills.

I personally didn't care for the Castrol Syntec ATF after trying it years ago. I was able to smoke the fluid in a transmission where Mobil 1 and Amsoil wouldn't smoke. Nothing like a cloud of ATF smoking out from under the car.
But, if a mineral oil works well, then the Syntec should have been good enough and is not to blame.

 

[Gary Allan]

As undummy points out, that's a decent amount of fluid for a simple pan drop. My son's C6 on his FS Bronco only took 6 without draining the converter ..but I'm crediting you for checking the level post change. If it was overfilled to a certain amount ..aeration would occur and slippage would account for the burned fluid. Not too much of an issue if caught soon enough since the fluid soaks up a decent amount of the insult for a brief period.

 

[confused]

Thanks for the ideas. I didn't personally do the pan drop, filter change, and refill - a mechanic with over 30 yrs experience whom I have trusted for 15 yrs did this. He's well aware of how to get the proper fluid level in an auto transmission.

The manufacturer says that the transmission is filled for life and routine transmission service is not needed unless you routinely tow - which I have never done.

 

[Big Jim]

quote:

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Originally posted by RF Overlord:

quote:

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Originally posted by confused: The manufacturer says that the transmission is filled for life and routine transmission service is not needed

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Yeah, but remember: when a manufacturer says something is "for life", they mean the life of the warranty, not the life of the car...

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Even if they do mean for the life of the car, they don't warranty it for the life of the car. They probably will not be there to stand behind it once you are out of warranty.

When I worked at a Volvo dealership (about 98 and 99) Volvo claimed that the trans did not require any fluid maintenance for life. Very consistantly an 850, S70, or V70 with the T5 (high pressure turbo) engine an unserviced trans failed at about 60,000 to 80,000 miles. Those that had the fluid changed every 30,000 miles did much better. I don't remember seeing one of them fail, but I'm sure they eventually would, but they certainly would go well over 120,000 miles (I saw several of them that had). Nearly the same trans was used in the non turbo engines and they did not fail as badly, but I did see several unserviced ones that failed in the 90,000 to 120,000 mile range. Volvo did not step up to assist with any of those repairs.

 

[RF Overlord]

quote:

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Originally posted by confused: The manufacturer says that the transmission is filled for life and routine transmission service is not needed

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Yeah, but remember: when a manufacturer says something is "for life", they mean the life of the warranty, not the life of the car...

 

[nascarnation]

One possibility may be an air suction leak at the filter neck to trans case seal. Next time you have the pan off, examine the elastomer seal very closely and replace it if any question about condition.