I recently got a crash course on modulators. The c6 in my 78 was shifting at around 2100 or so rpms at WOT. I pulled the vacuum line to make an adjustment on the valve and realized the vacuum line was full of tranny fluid. I blew the fluid from the line and turned the screw in half a turn and it would not shift right then either. It shifted very hard and higher rpms than I wanted. I knew it was bad but I was about to park it anyways to pull the motor and tune up the tranny. I never realized the little $12 part could mess up so much. I am sure you have already looked into it but the modulator might be going crazy.

As for the piece of gasket in the pan, hopefully it was just a piece of gasket and not part of one of the clutches. Mine had a lot of grit in the pan when I changed it too. I haven't had mine that long and I'm sure it was from fording water or something. The previous owner had so much rtv on the pan gasket that I know some of it came into the trans. Rtv is not required or recommended there anyways. I hope you get the shifting issues resolved or you are going to start tearing up U joints and popping more rivets.

 

Tonight I played around with it, shifted manually from first to second to third, then to first then to third, etc.. it shifted darn quick, snappy, better than a lot of new transmissions? So I have no clue what the deal is with that weird, highway 2-3 shift. 1/3-1/2 throttle, late shifts at 3k and BAM. Been fighting this one since the day I bought it!

Obviously, the harsh shift is probably because it's such a late shift going into 1:1 and I KNOW this shift is always a bit more rough, but it shouldn't be this bad.

 

When i pulled my c-6 and dropped the pan the entire bottom of the pan was coated in a gritty silverish colored paste. Almost looked like anti seize for spark plugs... Luckily the guy who rebuilt it cleaned it up and put a new gasket on after he did the innards. He said when he pulled everything out it was all garbage ca0sue none of it was useable any more, apparently the clutch disks were worn 1/6th of an inch past what it was supposed to be.

 

I'm guessing wear.. I've always suspected this trans was rebuild, due to .. well, nothing was bolted in 100% and I've had to retighten everything that would be loosened on a trans swap, but it has the original 1990 MLPs, so I dunno?

I think when I have a buck to spare I'm gonna swap out the solenoid shift pack or whatever it is called... and the connector.. maybe put in a shift kit? Been thining about manual shifting with electronics, it's possible on the E4OD, I can even do a manual TC lockup!

Stupid life problems always trying to come first.. grr, my Bronco is priority, women and family and friends need to realize that!

 

Haha i wish my bronco was priority but me having money for emergency stuff is more important.

BTW what kind of bolts loosen up on a trans drop? Like bell housing bolts?

 

yeah, it was housing bolts.. all were loose, trans mount was loose. I freaked a while ago and pulled my inspection plate but flywheel was tight.

There are a few bolts I can't get to, or can't even see.. I'd bet they're loose

 

That might partially explain the banging during the shifts. Get everything tight, check all the u joints, check the cross member, make sure you don't have any more missing rivets, check fluid and the modulator, and you should be able to narrow the issues down. I am chasing gremlins too. I got to drive mine for three days after I bought it before I decided to rip it all apart. I just figure I'll replace everything, change all the fluids, then narrow down the issues. My previous owner sucked pretty bad as a mechanic and it really showed during my tear down.

 

That means i am going to have to take a day and make sure all my bolts are tight. I wasn't able to get the fly wheel off though, i had my step dad holding the crank pulley in place with a ratchet while i tried turning the bolts out on the fly wheel but i couldn't get them loose. I don't have an impact gun capable of that kind of torque so that will have to wait.

 

Drivetrain flex is something I'm always on the lookout for.. I can feel it when driving and am always fighting to get it tighter. Pretty sure it isn't the cause of the issue though, I use to think it was.. it has taken me this long to realize that it is always gonna happen, regardless of fluid levels and always only when the trans is at operating temps. I have a few threads here where I said I thought I solved it, I just never did.

I don't actually have a trans modulator, mine is all electronic short of the neutral safety switch. The electronic side of it, the shift solenoids, people say they always stick and go out and replacing the solenoid pack always seems to make a huge difference in shift quality of their transmission. Apparently in later years they were redesigned for better shifts and reliability AND they just get worse with age.

I think I'm going to make this priority on my 'to do' list with money.. when I get time, maybe even today, I'm gonna cut off my driver's coil bucket and replace with bolts.. and I'm going to slowly go through my frame and replace all the rivets with bolts. I need to find a supply of fine thread or grade9+ though, as much as I use to love these 'by the pound' grade 8s I buy, seeing my truck bend one really confused me and is making me rethink the level of forces applied on my frame while driving.

 

Good GOD, broke that bolt again!!! I don't know what to do?! I think Rural King has some inferior stuff now. I use to use these dang bolts as hardened punches and couldn't even make a dent in them!

 

Picked up some grade 8s from Tractor Supply.. different supplier, and these weigh almost twice as much as the "Grade 8" i have been getting from Rural King.

Went home to cut off the old bolt and put the new one in.. and got distracted and pulled my intake to check out my valve train on the passenger side.

Of course both valve cover and intake gasket fell apart, of course I couldn't get a ride until after the autoparts stores closed.. but! well, broke my upper intake! The front passenger side corner just fricking broke off for no reason! Pretty sure I can get it to seal with some RTV, still, looks like an Edelbrock upper and lower is in my near future.

The valve train looked awful. Carbon everywhere.. maybe my old, bad O2 sensor was causing rich running conditions, which then caused carbon? More likely is I have an exhaust valve on this side not seating completely, or one even burnt through. Cleaned this head when I bought it, it's getting dirtier, not cleaner, and I'm doing 500-1000 mile oil changes!

Leaking exhaust valve would explain the excessive blowby.

However, i learned something today. Apparently a rocker fulcrum can only go in one way. I didn't know this, half of them were installed backwards and have been run like that for nearly 10k miles. Apparently they are slotted to help them move more easily. This might explain some of the issues I've been having with runability, because of this the rockers should be more noisy AND should cause excessive clearance between the rod and rocker arm. (edit: thinking about it, I think it would make them tighter, wouldn't it? )

It wont cause a valve to not seat, but sure as heck will cause exhaust valves not opening all the way and letting excessive exhaust in through the EGR and all kinds of other issues, like running rich. So I really think my motor will run A LOT better once I get the fulcrums in and the new push rods in.

Talking minor clearance differences, but more than enough to cause runability problems especially on an EFI motor! woohoo, this is actually good news for me. You could actually see more carbon buildup near the rockers with the fulcrum installed backwards. I can't explain it, but it was obvious. When I pulled a bolt with threads covered in carbon I looked closer at the rocker arm and that's when I saw the dirtiest rockers AND the one I suspected was being noisy on me all had backwards fulcrums.

My old push rods looked fine, but there was more variation in length than the new ones I bought. Thought there was suppose to be none? Whatever, gonna put the new ones in anyways.

Thinking about removing my smog system, not entirely sure yet. Spent 45mins just trying to undo the half inch bolt in the back. Though unlike everyone else, my thermactor system actually looks healthy and almost new. No rust, no cracking rubber lines. Probably because I seal my engine compartment up so well.

 

Man, it seems like if you didn't have bad luck, you would have no luck. I have run into the cheap "grade 8's". I think it's just a cheap bolt with a zinc coating. The weight usually tells you but it looks like you already figured that out. I found out the hard way when I was building a jeep and ordered some cheap grade 8 bolts online. Couldn't beat the price. They were garbage.

My DD is a supercharged grand prix. I got rid of all the smog stuff and ran an O2 simulator. It made a huge difference. I don't get all the stupid codes for running rich and all that.

I didn't even know that the rocker fulcrums could go in backwards. This makes me want to go check mine. I just reached the point where I am starting it for the first time.

 

Wow, sounds like you have been pretty busy breaking stuff , you know if you wrap the frame pieces in duct tape, and then put the grade 8 in, it will hold forever .

Also maybe you could get pictures? I wanna see the broken messy stuff.

 

Yeah I'm sorry, next time I go out I swear I'm taking pics.


and I realized the part the fulcrum sits in, on the rocker arm has a indented V (sort of), the bottom of the fulcrum does as well The rockers move more smoothly in the proper position. They also bind a tad during movement with them in the wrong position and feel a bit rougher, I'm sure they function just fine.. but for wear, noise and perfect clearances I think it's going to make a big differences putting them back in position.

I also noticed that it was tearing up the rocker arm, it was definitely grinding it down and scratching it up, but being so hardened it didn't do any real damage in 10k miles.

 

If you could do pictures try to get the rockers, i happen to no know what your talking about i know what the rocker is and sort of what it looks like but i don't know what it looks like backwards or normalwards... I remember pulling the pushrods off my 302 but i don't remember the rockers. It would help me for when i get new valve covers for TGM to make sure everything is kosher there.