Trans Leak

[stu in wichita]

Well, after 5 years of work, I finally took my '74 Challenger for a short drive.  There's still a lot of work till it's finished, but I was happy with the drive.  Everything seemed to work - engine ran fine, trans shifted nice and the car steered and stopped.  Today, I found a puddle of trans fluid.  It's coming out of the top of the filler tube, not at the bottom where it connects to the trans.  The car is a 318-2bbl with 904 auto.  It's not overfilled.

Any ideas what to look for?

-Stu

[jimynick]

Not trying to be offensive here, but how do you know it's not overfilled? By how many qts of fluid you counted putting in?

[stu in wichita]

No offense taken.  Thanks for the quick reply.

I changed the filter and pan gasket, so the torque converter was still full.  The TSM says 17 pints and I put right at 8 pints plus a quart of Lucas additive, so the total added was 10 pints. 

The dipstick reads right at full when checked with the engine running at idle and the trans in neutral.   

[70chall440]

This is an odd one; I don't think I have ever seen a 904 or 727 push fluid up and out of the dipstick, is it possible that the dipstick was wet from filling or something and it is leaking down at the trans?

[stu in wichita]

It's more than a little bit of oil from the dipstick.  It seems to have blown out with enough force to splash oil onto the firewall.  There wasn't  a lot of fluid lost, only a few ounces on the floor.

I suppose it's possible that I overfilled it, although I think I took every precaution.  One possibility is the dipstick is off - not likely since it's the same one that was in it when we drove the car 25 years ago.

Another possibility is that maybe it wasn't totally warmed up before I topped.    I only added about a pint, and it read perfect.  Could it be that  sensitive to a small amount of overfill?  Since it supposed to be checked in neutral, I assume that the level changes depending on which gear is selected.  Does anyone know which gear would indicate the highest or lowest level? 

I hope the weather is a little better this week and I'll do some more observation.   

Thanks for the help and suggestions.

-Stu 

[jhaag]

Check the vent. Only reason I can think of for fluid to come out of dipstick, would be a plugged vent. Even slightly over full it should not come out there unless pressure is building in the trans and pushing it out the path of least resistance...

[70chall440]

Absolutely agree with that assessment.

[360 'CUDA]

You can't really go by estimates like that, I always sneak up on the correct amount. For example, start with 3 quarts and see if it's on the dipstick yet.

If it turns out you have to remove some just pop the dipstick out and let it leak into a container. If you need to take out more a Turkey baster works well

Of course put the Lucas in first.

Just like when you service a rear end. Put the sure grip additive in first.

[stu in wichita]

Thanks for all the input.  I've driven it a couple more miles while watching for more leakage but so far, so good.  I must have had it overfilled, but it still reads the correct level.  I probably only lost a few ounces of fluid, so maybe it's okay.

Since it was sitting so long, maybe when I topped it off there was an air bubble somewhere that burped out taking some fluid with it.  I may never know. 

Getting it aligned today, so I can log some more miles and see if the problem is gone.  If not, maybe an A518 is in its future.

Again, I appreciate the input.

-Stu

[70chall440]

Glad it has worked out, many times frequent usage will sort out a fair amount of issues or really show you exactly what the issue is.