I keep noticing drops of red on the bellhousing despite a mechanic (with 30+ years of experience) already opening the inspection cover a month ago and telling me it isn't the front seal on the trans since the inside was dry. The trans is overfilled but the level isn't going down and the fluid is still red. The temperature is staying cool, so it isn't slipping. So where else could it be leaking inside the bellhousing and coming out? The engine oil is dark and I am changing it next week (almost 3k since the last oil change when I found this), so it probably isn't that. I am going to switch back to Mobil1 HM from Walmart since I can no longer find the old version of Royal Purple (API SL rated) and the new version is not only not as good as Mobil1 from what I hear, but is alot more expensive. The cooler lines are fine, the truck drives fine, so where else could it be leaking from judging from this leak?

 

A 15 year/100K+ old vehicle that does not leak enough from the transmission or engine to lower the level on the dip stick and runs fine sounds like a good used truck in these parts.

 

That's true, but a leak of unknown origin that seems like tranny fluid is really confusing. Trying to make sure that it isn't anything serious.

 

I know this thread is old, but for some reason it stopped leaking. I went under the truck earlier to change the oil and there was so little red on the bellhousing that there is no definite leak. Last time I washed the truck (including pressure washing the undercarriage) was Saturday. Doesn't seem to have any other issues other than hesitation or sometimes rough shifting. But since the fluid is still red, there is very little residue on the dipstick as usual and I don't get burned when I touch the trans cooler (IR thermometer reads between 90-110F on a warm day, I can hold my fingers on the bottom of the cooler for seconds before it gets uncomfortable enough to remove them) I assume the trans is operating properly and just watching the fluid level and condition is sufficient between changing it. It has 115k on it now.

 

Well I went to change the oil before and I can't believe it is almost 8 months since I first discovered this, but while there is a little red on the bottom of the bellhousing, there isn't much. Where is the overflow again? Could this just be overfilled fluid spilling out somewhere? I checked the dipstick and it is still a little above the max line and I haven't added any fluid in months. Maybe I don't need to do any repairs on this? I have almost 120k on the truck now.

 

I realize this thread is old, but could the leak be from the pan gasket? I mean it is against the airflow, but is it possible? I am going to have the pan gasket replaced anyway when I have the fluid and filter changed.

 

Old thread, I know, but any verdict on this? (If you happen to see this.) I have a similar leak only much, much worse.

Plus, mine is needing a head gasket among other things; I'm dreading to see how much it will be, but it has to be done.

 

Sounds like a rear seal on engine which requires tranny removal. If your mechanical at all you could do the head gasket yourself