***** sigh****
Conflicted,......again.
I started tearing apart the monster that is a 4R70W yesterday. Just getting it up on a bench to work on it required my 16 yr old help me lift the heavy assed SOB up on there.
There are several telltales that can give you an idea as to the internal health of an auto trans depending on what you do/where you look. The first, most obvious is to look at, and smell the trans fluid. If it smells and looks burnt, chances are that the trans is pretty well cooked.
Mine was dark, but to be expected in a transmission w/ potentially 60+k miles on it. It didn't smell burnt.
The next inspection is a pan removal.
4R70W's/AOD's have a big honkin' magnet in the bottom of the pan. If the clutches have failed in the transmission, that magnet will be coated w/ the debris that comes off of the metal pieces rubbing together.
My magnet was almost perfect.
When I bought the transmission rebuild kit, the guy at PATC told me that there were certain parts in an 4R70W that wouldn't handle the potential 600 RWTQ that this engine was potentially capable of, I told the guy that it would never see a sticky tire, or a drag strip,....but that I did want to roll into the throttle at 60 MPH, and light the tires.
Evidently,....that was enough to cause some little stock input shaft to fail.
So based on that,....I bought all of that junk, including the hardened replacement for that little input shaft. It was also the same reason I justified taking apart a perfectly good transmission. Because the more I got into it, the more it just kept sayin' "Why are you taking me apart?" The clutches and bands are perfect.
But once you start down that path,....all of the seals, and sealing rings are now compromised. so I push forward.
Until I make this kinda mess:
Now believe me when I tell you that all of this really doesn't bother me that much w/ one exception:
See that razor scraper? See that little doo-dad directly above it? That came out of the trans,.....not attached to anything. No idea where it came from, or where the hell it's supposed to go back.
Again, I trudge forward.
That Transgo kit in the pic is an AODE-3 valvebody conversion kit. I'm not calling it a shift improver kit, because this kit goes way beyond improving the shift feel. It allows you to completely convert the computer controlled trans over to full human controlled manual shift. ( w/ an electronically activated OD, and lock up on the converter)
The process to modify it is just like any other shift kit,.... You replace this valve, or this spring, you don't put this thingy back, you restrict this, you block that, or you drill this hole bigger. The problem w/ this kit is that you also have to drill the valve body casting itself.
At an angle.
Between two narrow passages.
In aluminum.
When was the last time you took a drill bit, put it on a piece of aluminum then angled the drill 45 degrees off of that surface and expected the bit not to just walk off? Well for some reason the guys at Transgo expect exactly that. That was the hardest part.
What I have left from that is the reason for my conflict.
The hole in the passage is probably significantly bigger than 1/8",....and the top of one of the fluid passages was made thinner where that bit touched it while trying to drill into the adjoining passage.
Like I don't have enough to worry about w/ the engine, Now I gotta worry about whether or not I just made an "improvement" that is some future fail point, causing the Alto red clutches and bands that I'm installing (that I really didn't need to replace) to burn the hell up.
Additionally, after you drill the valvebody, and make all of the recommended improvements, you have to drill the case for a vacuum fitting. The process to control the trans manually, also replaces some electronic control solenoid w/ an old school vacuum modulator.
Another point of conflict for me.
What happens to the transmission vacuum modulator when it stops seeing vacuum, and starts seeing 16 lbs of positive pressure?
It was all too much to worry about, Transgo was closed so I couldn't call dude and ask him those questions, so I went over to the other potential time bomb, and installed stuff that was sitting in some un-opened Summit box onto it.
Head studs came in yesterday, so I figured I'd screw them in for the sake of doing it. Also bolted on my SBF harmonic balancer to see if I'd have enough room to put the crank trigger wheel behind it. (I do). So I'll remove it an have the balancer modified to allow me to do that.