Transmission overheat?

[bradleyheathhays]

Sadly this may be the last post I make on the old '11 Crown Vic (320k).  So yesterday I heard a quiet hiss coming from the front which turned out to be a very small radiator leak...in the middle of a fin somewhere.  Doing errands around town today I kept extra coolant with me and added it as it needed.  After filling it up I make a 60 mph trip to a nearby city about 20 miles away.  When I get to a stop at the bottom of the off ramp, I hit the gas it it doesn't move.  No extra lights on the dash except for the check engine light which was already on for something else.  I put it in park and back in drive, tried all the gears but got nothing, not even in reverse.  Thinking it might have something to do with my coolant situation I checked it and ended up putting in like 1.5 gal of coolant which is much more than it's taken before.  Only thing I can imagine is that the leak got worse on the interstate and I didn't notice it.  Did the no coolant issue cause the transmission to overheat somehow?  There was a slight burning smell in the cabin so something definitely overheated.  The overheat light on the dash never came on (I think I have one?) and the engine ran fine the whole time.  I was traveling at 60 mph though so I wonder if that would be enough to cool the engine off while the transmission still overheated?

What in the heck happened and what do I do, besides sell the damn thing.

[Ajmboy]

That's pretty good to get that thing to 320k! Tranny lines run through the radiator also:

Did you overheat? Have you checked the transmission fluid color? Is it black and burnt? 

[davefrombc]

I  doubt the lack of coolant  affected the transmission..  Most transmissions  can  be  run a  long time with the  coolant  lines blocked off unless they're being run under very heavy  load. The  lack  of coolant  would have seized the motor  long before it  hurt the tranny.

[Ajmboy]

When you switch through drive and reverse, do you get any feeling that its shifting? Going into park work fine as well? Check your linkage, transmission lever, to make sure its moving. Are you low on tranny fluid possibly? 

[bradleyheathhays]

It seemed to respond like I wasn't shifting at all.  I think when I put it in one of the gears it got some kind of ticking sound but that was only briefly.  The shift lever seemed to move thorugh all the gears without hesitation.

I checked the trans fluid last week at it was full but I'll check it before I try to start later tonight, although I know that's now how you correctly measure trans fluid.

 

[bradleyheathhays]

Actually I remember the shift handle seemed to move more freely through the gears.  That common friction between gears didn't seem to be there.  It wasn't floping back and forth or anything but there def seemed to be a difference.  I'll have to pay close attention when I go back to it here in an hour and try to restart it.

The other possibilities that have been mentioned to me so far is a broken input shaft or the MLPS, and I don't know what either one of these is. Was told if it ws the MLPS that it would be throwing a code. So wouldn't you know I'm having a problem getting it read. Wonder if there is a way to get a multi-meter on whatever the MLPS is and test it?

Also, what is the input shaft and is it something in the drive line?

[davefrombc]

The input shaft  is what  transfers the  power  from the engine through the torque  converter to the transmission gears. I doubt it  broke.  I  have no  idea  what MLPS  is supposed to  be.

There's a number of things could have gone  wrong, from the linkage  from the  shifter to  the  trans  becoming disconnected to  the failure  of the oil pressure pump  in the transmission  or something   in the valve body   and solenoids that select the  gears .

[bradleyheathhays]

Just now got back from trying to get it going for the first time and no success. First I disconnected the battery for a few minutes like someone had suggested. Checked trans fluid and it seemed at a good level, but definitely dark and burnt smelling. The coolant I had put in there before was still in there so the reservoir was full. The front of the engine was caked with white which I'm assuming was caked on and dried coolant.

Started the engine and moved the shift lever through all the gears and that felt normal. Put it in drive and didn't feel anything engage at all. Gave it some gas and something whirred in the trans. The more rpms the louder the sound got. Almost sounded like something rotating...but it seemed to be coming right from the transmission.

I just checked the trans fluid last week and it seemed to look fairly new. What in the world could have happened to cause this?

So what do I do now? Is the trans toast or could I maybe try putting new trans fluid and filter in and see what happens?

 

 

[davefrombc]

Transmission is most likely toast .  If the linkage was fine  the tranny will  need to  be opened up, and dark burnt smelling fluid is a huge indicator  of a dead  transmission.

Changing fluid  will  do  no  good and just be a waste of money.

[bradleyheathhays]

Wow after all this and it turns out to be the rear end.  Just got it to my mechanic and he watched the driveshaft when I gave it some gas, in gear, and it turned.  So I guess that's where the sound was coming from.  Although my trans fluid smells a little, a mechanic who works on these crown vics a lot says the fluid always smells somewhat burned.  I'm super easy on this car so I'm not sure why the fluid would smell like that.  Newly changed out like 15k miles ago.

[davefrombc]

Glad your transmission  is ok.  It's a  lot cheaper  changing out  a differential  from  a wrecker.   UI know the feeling.  Years ago  I   thought my  transmission  or transfer case  had gone  on my 4x4  and it turned out to  be  the differential that time too.  Mine started with a bang and crunch and then  got progressively worse until I got it to the shop..  by the time  I  got it there   there wasn't  much left  of  the differential  gears