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Good Morning MaroonMonsterLS1,
Thanks for the early morning update, will put the valve body back together and move onto the next idem on the list.
Yes I think I will have my tuner take out 3rd lockup if it needs it after this is done. I appreciate you help.
Will let you know how it all works.
If you haven't already, invest in the sonnax o-ring'd end plugs. they cure some decent leaks.
Use the sonnax rev. abuse bore plug also
if AFL tests weak/low ...central valve bodies makes a drop in valve that works well for home-guys that don't want to drop the money on a reamer setup.
Hello,
Yes I have both, the Sonnax o-ring plugs and the Sonnax Forwar & reverse abuse valve kit that had the "abuse bore plug" in it.
My pressure tested good---two years ago and the fluid and the small amount of metal fuzz on the magnet is good when I drop the pan now.
So thanks
For the guys who are interested in omitting the #2 Check-ball and plugging the hole... the diagram changes to this:
(Note the #12 orifice size needs to be calculated and enlarged).
I sure hate when people do that! There's a lube orifice that feeds the low reverse clutches that's there for extended highway driving in high gear. I've seen distressed LR because of blocking the 4th accumulator case feed. Double stacking two accumulator pistons "Legs to Legs" with some 1/4" washers between them effectively blocks the 4th accumulator without cutting the lube to the LR clutches. Precision "Ring Shims" are avaliable from McMaster-Carr.
Not trying to be a dick, And it wouldn't bother me as much if driving a check ball in the case was easily undone!
Hello,
Just got the tranny back together. Drilled, tapped, and brass pipe threaded to plug up the old hole. ------So easy to undo if needed.
Have to wait for the test drive though, need to fix a badly missing motor.
I also normally would do this same procedure with the #4 Check-ball and #13 orifice as well.
Hello,
I will see how the 3-2 valve blocking and 4th mods work out 1st. I all so changed some feed holes to fine tune a slight - occasional 2-3 bump up-shift.
But thanks anyway, maybe later.
If change too much and things do not work out it will be harder to fix.
Hello,
Just got the tranny back together. Drilled, tapped, and brass pipe threaded to plug up the old hole. ------So easy to undo if needed.
Have to wait for the test drive though, need to fix a badly missing motor.
Do you see what I mean?
Yes.
I personally only use internal-Allen set-screws to block passages.
I do not care for cup-plugs or check-*****.
But I went from plugging passages on engines long before transmissions.
The larger passages on most engines do not take as well with cup-plugs... as they tend to pop-out from time to time.
Smaller transmission passages normally are no problem to drive a check-ball or cup-plug in a passage.
For example... Most builders will plug the reverse passage in the case of a THM400 with a cup-plug, to dual-feed the direct clutch.
Look at the far right passage... it is plugged with a set-screw:
I tap the passage in the center support for a set-screw; and use two THM200 Low-Reverse passage case seals in the THM400 case at the center-support.
It makes no difference in terms of transmission function.
So the preference is yours.
Last edited by vorteciroc; Jun 11, 2020 at 06:46 PM.
Hello,
I will see how the 3-2 valve blocking and 4th mods work out 1st. I all so changed some feed holes to fine tune a slight - occasional 2-3 bump up-shift.
But thanks anyway, maybe later.
If change too much and things do not work out it will be harder to fix.
I do not advise someone to remove and plug the #2 or #4 check-ball locations with out knowing that...
Normally some experimentation needs to happen in terms of sizing the #12 and #13 orifice sizes.
They become very critical when they are the only flow-path in and out of the circuits.
O... and If any of you guys are into the history of some of these transmissions...
You should know that the design for the circuits I have been posting; were first created for the THM200-4R Transmissions.
Even the 3-2 Control Valve (the actual part) was a complete carry-over to the THM700-R4 and early 4L60E.
Sonnax or transgo work great for bores that have too much wear.
But I've found that anything testing around 11 or 12inHg (at least on my tester) will usually clean up to 19-21 inHg with this drop in valve.
It's about 5 tenths over and has a nice annodize to fit the bore.
Its certainly not the best fix, because the valve lands are still the same length and don't offer any extra support to help keep the problem from happening again (like sonnax or t-go does) but...for the home guy...its 1000 times better than not doing anything.
And if the stock valve made it 200k miles...this one will at least make it another 100 HA!
As a side note...on blocking the check ***** and re-drilling orifices as noted above by vortec...be very cautious when attempting this.
Be prepared to drop the valve body a time or two to change your new orifice size.
After the hassle of trying this on a couple units, I've just found hole sizes that work with active checkballs, and I'll use torlon ***** to give the plate life.
Excellent information guys. I've been building for quite a few years, and I even learned some things here.
One thing I wanted to mention is that I'm ALWAYS using my Sonnax vacuum test stand to check the AFL valve readings on 4L60E valve bodies and rarely, if ever, find a worn/leaky valve here... Now on the 4L80E's it's very common, and as a course of habit, I ream and install the O/S valves in every 80E build.. But on the 60's... How often do you guys find the AFL leaking? Seriously.... I can't tell you the last time I had to ream a 60E AFL bore and install the over-size valve. Most will vacuum test in the 19-23 range.
Previously I was talking to one of the Trans-Go tech support guys about how the 60E's rarely ever fail the vacuum test at the AFL.. I remember specifically the guy telling me that if the AFL on a 60E is leaking that it, and I quote his words exactly "is a good thing". I can't imagine how a leaky AFL valve in a 60E could be a good thing. Did I misunderstand him? I remember scratching my head when he said it. But I've never forgotten it. I just test every VB, and ream and O/S valve any that are 18 or less.
Hello,
I will see how the 3-2 valve blocking and 4th mods work out 1st. I all so changed some feed holes to fine tune a slight - occasional 2-3 bump up-shift.
But thanks anyway, maybe later.
If change too much and things do not work out it will be harder to fix.
Hello everyone,
I finally have the truck running for a month now. The above mods worked great, only "feel" change I have is that the 3rd gear gear lock-up to 4th gear lock-up is less of a bump, which is good. So thanks to all that helped.
PS It is true that a ATF shower is good for the hair. [dropping the valve body with the tranny in the truck]
Looks like you're getting most of it figured out.
1/2/3 you have done just fine. The brake line to block is perfectly fine.
for step 4, you have noted the correct hole to block.
As for shift firmness, this will firm the 3-4 shift. It helps the band live a longer happier life, and helps 4-3 downshifts be nicer also (because you don't have a reverse quasi-accumulator trying to backfeed the band while the oil exhausts)
With that said, blocking 4th has NEVER been too aggressive for any setup I've had. From stock caprice classics, to my fiance' buick rainier (she's picky on shift feel too...probably my fault ha!), camaros, pickups, etc.
The reason your 3-4 shift is SO aggressive is because the converter is locked during that shift. Even a stock setup with accumulator and small feed hole will feel bad because the converter is locked.
If you will be towing in D4 shifter position, have 3rd gear converter lockup tuned out. I think you'll find that mileage will not change, and pulling hills or other areas where a 4-3 downshift needs to be made...you'll like how it tows better because the converter will be able to use the torque multiplication in 3rd to help pull that grade instead of being locked and making the motor do it all by itself. No lockup in 3rd also means that your overly firm shift into 4th will be fixed.
Hello,
On the 3rd to 4th convertor up-shift harsh shift:
With a smaller duration cam that pulls good at 2300 RPMs and with my turner's help I no longer have a harsh 3-4 shift.
I just got back from a trip pulling my small camper--against a stiff wind both ways. Kind of like having to walk uphill to school going and coming from school, in the old days.
At 75-85 in 4th going up hills in the wind, when it unlocks the convertor in 4th, it is able to cruise right along. My turner made it unlock sooner. The Yank convertor gives it enough RPMs that it does not need to shift to 3rd.
So I am a happy camper!
Last edited by Metalchipper; Oct 21, 2020 at 07:22 PM.
Time to put the valve body on 
Update--months later 