I have done the pan gasket on my 700r4 two times now and it still leaks. The leak is coming from the passenger side front of the pan I believe. It only leaks when it sits after i drive it. Im am extremely fed up with this damn car and am ready to sell it. Anyway, when I look at it, I can only see fluid from between the trans and the pan. I cannot find any traces of fluid anywhere else. I am so lost because I thought I did this job correctly both times. Anybody have any ideas???

 

cork or rubber gasket? is the surface dirty? make sure the pan bolts are torqued to spec.
also is the surface on the pan and trans nice and smooth?

 

Ok do it again but real slow.

Make sure everything is clean and dry.

Then coat both metal gasket surfaces with a thin layer of RTV silicone.
You can lay the gasket on the pan, on the wet RTV silicone but do not install anything. Let both dry and set, hr+, go eat, watch tv, download ****, come back out and then assembly, torque evenly and in steps.

If it leaks again, thats not it, or maybe it has cracked in that area where it weeps into the gasket area.

 

if the gasket is rubber dont use RTV or anything on it. if its cork then you need the RTV.
cracked what? make sure the gasket is NEW also
and make sure the torque is at spec.

 

The second time I did it, I used a gasket i purchesed from GM. I used a paper thin layer of rtv on the pan surface to basically glue the gasket on the pan. Both surfaces were EXTREMELY clean and DRY. This is why I can understand why it still leaks.

 

It isn't the front seal leaking is it? It can dribble down and drip from the front of the pan.

 

No, it is for sure not the front seal. I just checked it again today. I drove the hell out of it last night and it leaked about a quarter size puddle over night. THis **** is a mystery. It looks like its coming from the gasket. It leaks right around the dipstick tube but doesnt appear to come from anywhere else but the gasket. Ill check it again later today.

 

The seal around the fill tube can leak. Also, that's the same side as the in & out trans cooler lines. Check to ensure that the leak isnt orginating from those areas. The cooler lines themselves are subject to hair line cracking. While you're under the car checking the fill tube rubber gasket and cooler line ports, run a clean rag along the cooler lines. Hopefully you'll see red from somewhere other than the pan gasket.

Good luck

 

You have to be pretty talented to screw up the pan gasket. Look elsewhere for your leak.

 

Well, I found out where it is leaking from. Its leaking from the kickdown cable seal. So, I pulled the cable out. Then I pulled the old seal out. However, I could not get the trans surface completely dry of trans fluid. So, I installed the new seal anyway. Wow, to my supprise, it leaked from the kickdown cable again. So, my new question is, what is the best way to install a kickdown cable seal?

 

dunno on the 700, I know the Th350 has 2 kinds, a boot type seal and a O-ring. I used the boot.

 

So, I pulled the kickdown cable back out. This time I siphoned about a quart of oil out of the trans, using a 1/4 inch clear hose. I siphoned it right out the kickdown cable hole on the trans. Now that the surface was nice and dry, I instaled a new gasket and hooked the cable back on the hook. Getting the cable to hook back is a pain in the ***. So, no more leaks. Will test it out tomorrow to see if everything works. Thanks for the help guys. Here is a pic: