tranny dipstick leaking WTF?

badluck b · #1 (**permalink**) 07-03-2008, 12:38 AM

So I moved my 99 f250 powerstroke for the 1st time in a few weeks and it starts leaking fluid from the dipstick tube at the top. I pulled the dipstick and it spewed all over. Wtf?

75F350 · #2 (**permalink**) 07-03-2008, 12:45 AM

Welcome to the site:

Sounds like the truck is mad because it was parked for too long, and it is letting you know that it needs love too.

All kidding aside, I do believe that you have a blocked vent. The vent is located on top of the trans. Air has to move out when the fluid heats and expands, and if it cant vent pressure will build, and it will find a way out. The dipstick is the easiest.

aldridgec · #3 (**permalink**) 07-03-2008, 03:11 AM

Bugs like the hole and could be living in the vent clogging it. Also mud daubers.

badluck b · #4 (**permalink**) 07-03-2008, 08:34 AM

thanks guys. What does the vent look like and can I clean it without pulling the tranny?

badluck b · #5 (**permalink**) 07-03-2008, 06:06 PM

I'll try to find the vent. I also heard it could be the torque converter draining back. Will it fill back up b running it or will it smoke the tranny?

F350-6 · #6 (**permalink**) 07-03-2008, 09:28 PM

The vent should be on top near the front of the tranny. I'm no tranny expert, but the fluid should be pumped through the torque converter. Since the fluid is pumped through the tranny, torque converter, and transmission cooler, the TC draining back sounds like it would only happen if you had a line blocked somewhere.

How old is your fluid? If the vent turns up clean and the fluid is old, maybe doing a flush will give you a better idea of what's going on. We have an excellent DIY article on the flush written by a member here Changing ATF Fluid in a E4OD and 4R100 transmission .: Articles

Mark Kovalsky · #7 (**permalink**) 07-04-2008, 08:15 PM

The torque converter will fill by running the engine. It's the only way to fill the torque converter.

The torque converter will drain back because the anti-drainback valve has a slight leak. Plugged lines have nothing to do with it.

If you do use that excellent article to change your ATF, be aware that it is a bit out of date. Ford has discontinued MERCON and changed MERCON V to be compatible with all transmissions that used to use MERCON. So use MERCON V and ignore where it says not to.

F350-6 · #8 (**permalink**) 07-04-2008, 08:24 PM

Good info as always Mark. Any idea what he should be looking for in terms of shooting fluid out of the fill tube?

badluck b · #9 (**permalink**) 07-07-2008, 06:34 PM

Thanks everyone