So I found the source to the leak I had on my tranny, and it was the speed sensor (it completely broke off). So here's the thing. When I changed the sensor, I put in 2 quarts of tranny fluid to fill her up, and ever since then, I seem to have lost the tranny dipstick, so its hard to monitor the fluid level without one. So about a week later (today) I poured in another quart to be safe, (car was hot and running in my driveway) so i poured in the quart. Then within 5 seconds I see smoke from underneathe, and i crouch down to find fluid leaking onto the floor and the pass. side header, causing it to smoke. There was a good amount on the floor, like 2 square feet covered, but not 1 quart's worth (which I poured in). So my question is, does it sound like I have another bad leak? Or is there some kind of overflow valve on the tranny, which caused it to spill because of me potentially overflowing it?

 

Sounds like you may have it overfull and its venting the fluid out the vent at the top of the trans.

 

thanks a lot bro.. i really appreciate the input

 

Just to let you know, it's actually more dangerous to the transmission to overfill it than to underfill it. You're better off being a quarter quart low than a quarter quart too full...at least that's what I've always understood.

 

Choco though I watch your post and think your a great guy I would have to disagree, Watching what happens to a presure guage with and underfill is scary. Max line to min and back in a spilt second over and over, Overfilling alot is bad but I would rather be a 1/2 quart over than low any day with the 4l60e unless it has the deep pan , They have very little reserve to start with .

 

That's just what an older mechanic told me. He generally knows his stuff, but I'm sure he's way more familiar with TH350's than 4L60E's. My transmission is filled slightly above the full mark. When I changed the fluid, it was originally a hair under the full mark, and I chose to add a little more because the shift is more satisfying with a tad more fluid. I went a little over the mark; I couldn't get it perfect. I hope it's not a bad idea on my part.

 

Nah Choco, you'll be fine. Keep an eye on it and if it tends to leak or seep anywhere near the pan rail then you might want to adjust it... but you should be just fine.

g

 

Alittle over the full mark is fine, The fact that the shift fels better should tell you something , The 4L60E keeps so little fluid in the pan that why I really like the truck deep pan.

 

Well, this summer I'm in need of a trans fluid change (last one was last year), and I was thinking about drilling a hole in the pan and installing a drain plug and also putting on a trans cooler just for the heck of it (they're only $60 and they can only help, even if the trans is bone stock). Maybe I'll put on a truck pan instead since they have a drain plug, right?

How's the clearance with the truck pan compared to the LS1 trans pan? Is there a big difference in ground clearance?
I may actually get the transmission flushed instead of just changing the fluid. There's only 45k on the car and I changed the fluid at 30k.
No leaks *knocks on wood*

 

The truck pan is a fine addition, allows one to keep ones fluid fresh by simply removing the drainplug. It is about an inch deeper, depending on the pan you currently have, so not ground clearance issues either! And yeah, a cooler will definately help in the long run too.

All smart upgrades in my book.

g