'85 5th avenue with massive tranny leak

[Dapert]

Car drives fine when full but once it's parked it will dump a massive amount of fluid. My son replaced the pan gasket and filter but no change. He crawled under the car and says it looks like it's coming from the top. We are handy and can fix most things but transmission has just been a no way Jose task for us. Put one of those round oil change buckets under it and it was half full of fluid by morning.

I know it's impossible to troubleshoot a description but tying to get a ballpark on cost to have it serviced, repaired, rebuilt. I'm sure that is a pretty wide range as well but again just a ballpark.

 

[78VOLAREWAG]

Car drives fine when full but once it's parked it will dump a massive amount of fluid. My son replaced the pan gasket and filter but no change. He crawled under the car and says it looks like it's coming from the top. We are handy and can fix most things but transmission has just been a no way Jose task for us. Put one of those round oil change buckets under it and it was half full of fluid by morning.

I know it's impossible to troubleshoot a description but tying to get a ballpark on cost to have it serviced, repaired, rebuilt. I'm sure that is a pretty wide range as well but again just a ballpark.

It could be clogged cooler lines boiling the fluid and pushing it out a vent on top.

 

[Justwondering]

Dapert - have you purchased a service manual for your fifth avenue?

I knew nothing about cars in general when I joined the forum about 2 years ago and that manual has been so helpful for me.

The folks on this forum provide excellent guidance and gave me the confidence to get many items fixed myself. I'll post what I find about cooler lines in just a bit.

 

[MiradaMegacab]

Technical Tip #6

 

[Justwondering]

There’s another 50 pages in the arrvice manual on transmissions but maybe these items will help

 

[Dapert]

Dapert - have you purchased a service manual for your fifth avenue?

I knew nothing about cars in general when I joined the forum about 2 years ago and that manual has been so helpful for me.

The folks on this forum provide excellent guidance and gave me the confidence to get many items fixed myself. I'll post what I find about cooler lines in just a bit.

Not yet. Just getting started on this journey. I saw something about the shift lever shaft seal and as soon as I told my son he said that's where it's coming from. Saw a few videos on sure does look like that could cause a hefty leak if it's bad. Looks like a cheap fix so going to start there.

 

[DCAspen]

Let us know how you make out.

 

[Dr Lebaron]

There's a grommet that goes to the shifter linkage that will pour fluid when bad.

I own one that I need to fix for that.

 

[Dapert]

There's a grommet that goes to the shifter linkage that will pour fluid when bad.

I own one that I need to fix for that.

Is that different than the seal?

 

[Dr Lebaron]

Is that different than the seal?

 

[slant6billy]

Typical leak areas is the front seal (behind the torqueconverter) or rear seal at the drive shaft. When the front seal is bad you will have a smoke cloud after 20 mins of driving. Thing is the mopar 904 or 727 trans are amazing pieces of machinery. A leaky trans can still shift and operate without any performance issues. Likely the vent is purging, but look at the trans lines, shift lever, speedometer cable housing and neutral safety switch connector. I recomend getting to a carwash and getting underwash done.
That way you r seeing fresh areas of leaks.

 

[BudW]

There are a few “leaky” areas on Chrysler transmissions.

Only a few areas for “major leaks”.

Generally the two areas for major leaks are: a cracked transmission cooler line (will leak mostly when the TCC (torque converter clutch) is engaged) or the front pump seal area.

Chrysler torque converters do have a tendency to crack in the area mentioned in post #4, and the crack will make the front pump seal fail quicker than one would expect.

Matter of fact, the front pump seal is leaking on my ’77 wagon.
Hopefully I can get it to last long enough to get other projects in front of it, done first . . .

Usually when a front pump seal goes, it goes quickly and will empty the fluid out of a transmission in a few moments – leaving a wide path of fluid behind the car.

Transmission cooler lines can be fixed if cracked using rubber hose and hose clamps or a metal line splice kit. The fluid pressure on cars without TCC is not bad – 5 to 10 PSI (cars built up to early ’78).
Cars built late ’78 and afterwards generally have TCC (sometimes known as lock-up clutch). The fluid pressure on those cars increase to 60-80 PSI when TCC is engaged – so on those cars, the rubber hose fix will only be a temporary one.

If the front pump seal is leaking – the only fix is to remove the transmission assembly . . .
BudW

 

[Dapert]

FIXED!!!!!!!! Turns out it was the $5 seal. She's been running around town fy or the last 30 minutes and not a drop.

 

[Justwondering]

kicking a$$ and taking names!