Hi all I've got a problem similar to the one BRYAN0010 posted about but didn't want to hijack his thread so starting this one.

Here is the story with my 4l60e in my 97 ls:

First, I had P1870 error code and noticeable transmission slippage on the highway.
I dropped the pan and installed a tekpack valve, put my filter and pan back on.
Now the bad part: I wasn't paying attention and dumped nearly 6 quarts of fluid back into the tranny after installing the tekpack. (Only about 4 quarts came out when I dropped the pan, of course).
I didn't catch my error right away, in fact I drove over 200 miles across a couple days before realizing that there was just way too much fluid in there. Note, it was still driving perfectly at this point. TC lock no problem, smooth shifts, etc.
Still, I knew I needed to get the excess out so I got a hand pump and took out about two quarts through the dipstick tube. I thought that would about do it and no harm done right?
So I took off to head out of town, shifting great and TC lockup great, everything great until about 10 miles down the road suddenly smoke rolling out from under the hood and under the body.
I pull over immediately and pretty easily can see that the vent tube tied to the top of the dipstick has been spewing lots of fluid which was hitting the exhaust.
I let it cool down and drive it home (stopping once on the way to let it cool again, as it started spewing fluid and smoking again).
It then sat for 4 days as I had no time to investigate further.
So 4 days later I pressure wash everything off, use my hand pump again and remove another 2 quarts. I start it up and seems fine. I slowly add fluid over the course of 45 minutes, shift the gears, go for a 1 mile drive, etc, until the level seems ok. Hard to read the dipstick at this point. Shut it off in the driveway and go in for the night.
This morning I start it up and wipe the dipstick, jam it in and comes back right on the cold mark. Perfect!
I take off for work and get about 8 miles before vent tube spews fluid everywhere and onto exhaust again. Crud!
So now I don't know what the heck. I let it cool a bit, drove halfway home before the smoke started rolling again, pulled onto a side road and let it cool a little more.
Then I drove home 30 mph backroad the last 5 miles and had no issues.
Still shifting smooth. All gears work. TC lockup works.

So... do I still just have too much fluid or... did the front pump seal blow out? The pump seal was BRAND NEW last month, as we had the motor out anyways.

Any way I can be sure its the seal without dropping the tranny? I don't know whether I should drop the pan and try refilling one more time or just go straight to pulling the transmission. Any thoughts? Any ideas why it would be fine for a few miles and then blow fluid?

One thing is certain, I will never overfill a tranny again

 

Zero out all codes and see if P1870 comes back. If it does it's not truly fixed just masked. You will need a better quality scanner to see if it is getting more than 200 RPM's of slip. If the torque converter has had a slip problem, it is probably glazed over. I would pull it and overhaul it with a new converter. That's me though and it is my specialty. I have had over a 90% success rate with a Gil Younger (RIP) orange box shift kit and the P1870 code. Only the severely glazed converters required a Trans pull
Keep us posted

 

Thanks for the reply Tranzman! I cleared all codes after I installed the teckpak. It has thrown no codes since then at all. My scanner has live data output so I can see the RPMs, it appears to be fully locked up on the highway although I guess its hard to say for sure without knowing exactly what the RPMS should be at say 60 MPH. All shifts seem good and working well except for the spurting of fluid after a few minutes at 60 MPH.

It can idle for an hour in the driveway and not spit any fluid, it can drive around 30-35 MPH no issues... still just weird that it didn't give any trouble until 200-250 miles AFTER installing the teckpak, I don't know what to think of that.

It did have P1870 for quite a while before being fixed, is there any specific way to inspect the torque converter to determine whether it is glazed over? Getting a new one is not really the end of the world. Given enough money I would get a new TC and have my 4l60e rebuild but... not much monies available right now.. hence me poking around hoping someone will tell me to put in a couple seals and try it again.

 

Here is what I've found so far:

The hose at the dipstick tube is a transfer case vent
The transmission is a pain in the *** to remove
There appears to be a return hole in the back of the tranny (see pic)
Hanyes repair manuals USED to be good. Now they suck.


Here is what I've installed so far:

Shift kit. (Identified known issues and cool to install)
Additional transmission cooler

I'm in the process of installing a reman transmission. Hopefully that will resolve the issue. The fact that the fluid was coming from the transfer vent has me a little concerned though.

I've been told to add LUBEGARD. I was unable to locate it at the autoparts store but I did find some Lucas Automatic Transmission Conditioner. I'm going to add that when I finally get the replacement transmission installed.

 

A transfer case vent eh? So probably... I overfilled the transmission, blew a seal to the transfer case (?) filled that with fluid (which now spews out at highway speeds)... that would explain why draining and refilling the transmission didn't help, cuz the extra fluid was in the transfer case not in the transmission itself. Seems legit?

I watched some youtube videos on pulling the transmission but have not tackled it yet, been busy with other cars. The blazer has literally sat motionless this whole time and will be for a while yet until I have some free time =/

I really appreciate the input guys, here I was thinking I would need a new tranny but perhaps I can get by with some seals? Or, do I have my theory all wrong? (could easily happen, knowing me)

 

before i pulled the transmission I would check the fluid levels in the transfer case, if it's overfull i'd pull it and replace the front seal in it - then get all fluid levels where they belong and see what happens

 

I took a pic this morning of the input side on the transfer case. There is s seal on it. I think that the problem that I was having was an overheating transmission pushing the fluid back into the transfer case and then out the breather. The transmission cooling lines where hot to the touch.

 

your trans cooler lines will be hot to the touch even with a remote cooler - do you have a temp gauge in trans if so how hot is it geting - i could be wrong but IMO with both of you guys the seal on the transfer case is bad letting trans fluid into the transfer case and over filling it - once over filled it has to have a place to go so it pukes out the vent tube - also it could be running the trans low on fluid and causing slipage -

 

I checked both in output and the return lines while the engine was running and both of them were hot to the touch. I would think that the return line should be cooler than the output. I haven't got a chance to install a temp gauge on the transmission yet. I looked at the seal on the transfer case. It looks like it's designed to keep the fluid in it. I could be wrong though. I will find out once I get the transmission put back up in. I had topped off the fluid the last time I drove it. By the time I got back on a 10 mile drive it was low again. I should have an update soon once I get the time finish up. I noticed that the rear main seal was leaking also so I'm going to replace that also.

 

I have have two vehicles that have a trans gauge a 88 rx7 with a slightly beefed sb 350 - 2004r combo with a large remote cooler, trans temp runs around 140-150 can be higher if being raced - my 98 dodge cummins with stock remote cooler runs around 160, higher if towing - both intake and output lines are going to be hot enough to burn you if hang on to them - think of it as being the same as grabing the radiator hoses on your engine both are going to be darn hot and by feeling them you wont be able to tell the difference in temps between the two - it's been a few years since i changed one but if i remember right the seal between the trans and the transfer case is a double sided seal that keeps the fluid from going either way - if you see no external leaks on the trans or the transfer case and if the fluid level in the transfer case changes the seal is usually bad and needs replaced - just my 2 cents