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What happens when you run out of ATF transmission fluid?


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Here's what happened to my 1996 Legacy L AWD with auto trans:

 

Three weeks ago, I went to a major national chain service facility and had a transmission fluid flush done to my car that entails splicing the ATF fluid line to the radiator / oil cooler and exchanging all the trans fluid. Everything was fine until this Saturday aftenoon, while driving at 45-50 MPH, the trans suddenly starts to slip and the engine revs like it's in neutral. I coasted to the side of the road, but it turns out the spring clamp that held the rubber tubing to the oil line had come apart, and the trans fluid got blown out on the road.

 

So, the car gets towed to another branch of the service company where service technician #2 installs a better worm gear screw clamp around the hose, adds about 3.5 quarts of trans fluid (all it'll take in the sump) and then tries it again but still it slips BIG TIME. He ends up revving the *$^#%! out of it to move the car from the parking lot to inside the garage -- lots of noise and very little movement. If revving a trans without oil would be like revving an engine without oil, it's gotta be toast by now. :confused:

 

Now the service manager say they'll have their insurance adjuster check it out Monday a.m. The manager seems to have already accepted responsibility as he's already agreed to pay for the towing, a cab ride and a car rental. BTW, the oil lines are attached to the frame just below the battery, and it looks like the first tech may have bent the metal tubing towards the back of the car a bit, as the tubes are no longer parallel. I took pictures of the pipe where it came apart from the hose, and I have the original spring clamp which looks a bit mangled, so I think I've got the evidence I need to show it was their fault. (I can handle the inconvenience of an honest mistake, but if the insurance company jerks me around, I'll be slamming this company by name in whatever forums I can.)

 

Question: What happens inside the case when an auto trans runs out of fluid and gets revved? Major damage? Do you rebuild it, or replace the whole unit?

 

Thanks in advance,

 

Brian

Bright1 on USMB

 

P.S. Plaintiff's photos Exhibit A, B, C just added for your viewing pleasure... ;-)

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slipping an at like that is bad because it will chew up the clutch materials fast. Plus it can result in localized overheating. If you get the at replaced by insurance, id push for a subaru rebuilt not some junkyard unit. But a sub rebuld is a few thoousand so expect them to balk.

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I did this kind of flush on my Baja's A/T just a couple weeks ago. I don't really know about A/T function in a specific way, but I would have thought that if the transmission pumped all the fluid out of itself (which is what happened if the cooler line came apart), then there shouldn't have been any burned clutches or anything because no power or torque would be getting into the transmission through the empty torque convertor. Then again, what do I know? :-\

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Torque converter wouldn't have necessarily been empty. The pump would definitely have started to suck air and maybe circulate that through the system. Probably lost more fluid than what the tech put back in before reving it like crazy to get it moving.

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