Hey guys I've got a 2nd hand 4l60e I stripped to rebuild my box that had damage to some hard parts. The box was apparently only a few thousand KMs old but started slipping. I did ask any questions as long as it had parts to fix mine. Anyway I stripped it today to discover 3/4 clutch failure (raybestos z Pak) but box did have some good stuff like new reverse drum, wide band, transgo shift kit and billet servo.

I already have a new Corvette servo for my box but should I use this. I heard they can make shifts a little harsh. No clue what brand it is. what you guys think.

I'm still planning on using my new Borg Warner hi energy not the wide band I found in the case

 

Those servos are from Superior Transmission.

You have their 2nd servo and their 4th servo.
Both of the servos are the largest (most aggressive) piston models produced for the 4L60E

The Sonnax 2nd and 4th servos are slightly less aggressive and much more popular over the Superior servos.
Keeping separator plate orifices small here can help tone down a large servo if needed.

Most people are happy with the Corvette servo unless they are a person looking for extra firm gear changes or have a really loose torque converter and need a larger servo piston for a better apply ratio.

 

Sonnax Dual-piston 4th gear has more apply than the superior.
But for single piston designs, superior is largest.

Corvette servo with wide band and new Reverse Input drum has served me well at builds over 600hp
At this point, I'm not going to mess with a recipe that works until it doesn't anymore

 

I went with this expecting to use Borg Warner hi energy band and Corvette servo but wasn't expecting to land a freebie.

band .098
1-2 .078
2-3 .118
3-4 .118

Also when I installed HD2 kit I put no spacer with accumulator piston and everything has been carried out as per kits instructions.

No clue what brand the wide band I found in the box is. Friction material is dark maybe even black but no markings on in to indicate a brand

I unfortunately have to run a standard converter modified to have a 2200rpm stall but only until I get my 9" dominator 3800 rpm stall rebuilt and installed again

 

The Extra Wide black/dark gray band is the Alto Carbonite band. This is a good band, a little harsher on the part throttle shifts. I prefer the BW Hi-E band for almost all applications, as they work and wear very well. The Corvette servo will give you fairly smooth shifts at part throttle. When using the HD2, use .093" with the stock diameter torque converter. Install the white spring at the 2nd accumulator in the valve body. The 3-2 feed hole (almost in the middle of the separator plate with a checkball next to it) should be 120". Band release leave at .082". When using the 428 accumulator housing, use the spring seat as per instructions. With the 937 housing, no spring seat. Springs and piston only. Grind off the ten nubs on this accumulator piston. With the 9.5" torque converter, you can drill the 1-2 feed hole to .099". Leave the rest the same as I had stated here. The Superior 2nd piston is for drag race only. Very hard to get a fairly smooth part throttle shifts, as they do not use "cushion springs". It is very hard on the band anchors (band breakage can occur) when the feed holes are larger than they should be. The Sonnax 2nd apply servo is the best to use for high horsepower and be very streetable, and is much easier on the whole gear train, when compared to the Superior 2nd apply servo. Since you have the Superior 4th apply servo, use it. It offers a 10% more apply area over the oem 4th apply servo. If you plan on making 3-4 WOT shifts more than just once in awhile. Then drill the 3-4 feed hole to .140" - .155". Go with the Sonnax 4th apply servo here if you are making higher horsepower and you drive aggressively. It offers 40% more apply area than the oem 4th apply servo. This will keep the band alive for a long time. If you change from the Corvette servo to a larger one, let me know as you can change feed holes to increase the torque capacity here for handling more horsepower, on the 2nd and 3rd shifts. Hope this helps here.

 

I think I'll just stay with my new Corvette servo and sell the billet one to recoup some costs. Not interested in firming up 3-4 shift. Don't think I've ever had WOT in 4th other then a couple back street drag races back in the day. 3rd gear top speed puts me around 200km/hr so kind of unnecessary

I've already made the separator plate holes those sizes so not sure I can shrink the band hole back down that much and I thought keeping the 1-2 hole on the smaller side was recommended.

With the install of HD2 kit, .500 boost valve and Corvette servo the shifts are definitely gonna be firmer then I've had.

I did use the white spring if memory serves but that's what the instructions said to use if I had a Corvette servo. I'll definitely look into which accumulator housing I have and adjust accordingly to your instructions Dana. Thanks mate all the advice helps.

I didnt do anything to the 3-2 feed hole unless it was in the transgo instructions to drill out. I would definitely be interested in firmer downshifts to help slow the car down (commodore brakes are a little mediocre) any instructions on modifying the valve body or seperator plate I'll take ✌️

So far I've finished my pump(all new hard parts and hi rev kit), reverse drum, input housing all set up (new HD sprag, 7 clutch upgrade, moulded pistons, stiffer springs), shift kit installed with sonnax 2-3 valve

All I got left is install new heavy duty sunshell, replace the seals and clutches related to the back half/output side of transmission

 

every one hates those to firm 3-4 shifts......said no one ever !

the sonnax servos are great ....if you can afford them use them IMO

 

Thats a typo on the 3-2 hole. He's talking about the 2-3 AKA 3rd feed.
In fact if you read Danas hole size recommendations through the years they change often, and I don't think it's application specific.

And about the 2nd feed being bigger, it's all in the accumulator set up. The feed hole can be bigger (up to mid .090 range) if the accumulator is set up to match and a corvette servo used with the transgo springs. Dana used to be specific about the 1-2 accumulator piston, either use the late style without the three legs or grind the three legs off. I have no idea why he wants to grind the 10 nubs off of the piston. In the deep housing this will provide soft shifts at low throttle and firmer shifts with throttle (with the recommended feed hole size) And it can easily be changed by removing the pan and three bolts instead of the whole valve body.

IMO you need to feed the apply components to make them live and if you don't like how it shifts either deal with it or change it with the accumulators, a higher stall speed will cushion the shifts in the drivers seat (not necessarily at the transmission).

You can also do the firm third modification below. No, it doesn't effect the 3-2 downshift at all.

 

Haha no I just meant the shifts will already be firmer then before and I don't think it's worth spending the extra cash on this particular build on something that's never bothered me before

If I had cash the box will be filled with all sonnax goodness I wish I could afford

 

Yer I already assumed the feed hole size thing is a trial and error based on the fact every build and engine requires a little different something

Blocking the 3/2 control valve doesn't have any negative effect? When you remove the spring what stops the valve from moving back and forth. Do you make a plug and put a spring on the side of the valve?

The only thing left that I wanted to buy. The unit I'm rebuilding had a burnt forward clutch assembly. I wonder if I should install a sonnax pinless accumulor piston for the forward one only just incase there was a hydraulic leak around the pin causing the failure. The valve body did look in good shape but can't figure out why the forward clutch failed. Unit did have 180,000km on it

 

There is no harm in any of those valve-body modifications as well as a few more that have to do with what you have mentioned:

-Block the 3-2 control valve
-Block the 3-2 down-shift valve
-Sonnax pin-less forward accumulator piston
-Sonnax pin-less 2nd accumulator piston
-Sonnax forward abuse valve end-plug
-Sonnax reverse abuse valve end-plug
-Sonnax O-ringed end-plugs

All of these valve-body changes are correcting circuit leaks normally found in the 4L60E valve-bodies.

Note: TCC valve-train and AFL valve-train are almost ALWAYS worn and should be corrected with tooling and new valve-train

 

Sweet. I've taken everything under advisement. I thought a pinless 2nd accumulator piston doesn't work with the transgo HD2 kit I have?

Do people still block the 4th accumulator and remove the piston? Was thinking of doing that also. Do you just remove the pin, spring and piston and knock a checkball where the pin used to go?

How to you guys go about blocking off the 3-2 solenoid and valve and I'll do it

Was also thinking of disassembing the input drum again to add those oil feed holes in the new forward sprag I've heard Dana mention in other post

 

It was not a "typo". I said to enlarge the 3-2 hole that TransGo has you drill to .093" to .120". It is the feed hole just above the 2-3 feed hole. With using the Sonnax HD 2-3 shift valve, you need to grind the 4 slots in the steel servo spring cover on the Corvette apply piston. These instructions are in the TransGo 700R4 Junior Shift kit. The reason here is to eliminate some of the downshift clunks when using the Sonnax HD 2-3 shift valve, which will be more pronounced when in drive. With the addition of this valve, the transmission will act just like the 700R4, which has the overruns on in when in "drive". Stock 4L60E's never had this when in drive. When blocking the 3-2 valve as shown in the posted instructions, you can open up the band release hole (when using the Corvette servo) to .101" and the 2-3 feed to .135". When using the Sonnax 2nd apply servo, you can open the band release feed hole to .104" and the 2-3 feed to .140" - .155". Do not use the Sonnax pinless for second accumulator. It will not work. I did say to grind the 10 nubs off the second accumulator piston. The reasons being is that the blue spring eats into the nubs, and eliminating them will stop that. The other reason is to soften the 1-2 part throttle shift, even more so with the 937 accumulator housing. Leave the 3 large legs alone. The TransGo Isolator converter valve will solve lockup problems by eliminating the pwm. This valve is now a on/off valve. The stock LS torque converter is 30 or more pounds heavier than the 9.5" torque converter. A smaller diameter torque converter is much easier on the drive train. Less shock on the shifts. Do not disable the torque management completely. 50% is a pretty good place to start with. Transmissions live much longer with it being used. On the input sprag assembly, if it has the brass retaining rings, add 4 - 6 holes (.125") on the retainer that makes contact with the overrub hub. Leave the other retainer alone. This will improve the wear, where the overrun hub makes contact the retainer.

"Everyone hates those to firm 3-4 shifts......said no one ever!" That's a good one...They are not the same as the 2004R, which can have a very firm 3-4 WOT shift.

 

Haha maybe I will use the billet 4th and cover since I have it and it was free. Sure I can sell the 2nd to some 18 year old with a V6 who wants to chirp gears.

I can not find any instructions for blocking 3-2 valve. Can someone maybe post a link. If I spend any more time researching 4l60e things my wife will start to think I'm having an affair typing away on my phone all day lol

What about blocking and removing 4th accumulator piston?

You mean grind 4 notches like that?

 

Yes, that is what you want to do here when using the Sonnax HD 2-3 shift valve. The TransGo HD2 kit has you blocking one valve and the other valve to be blocked inboard is shown in message #10.

 

Yer I was just wondering what you guys use as the "install something here"? I'll use a tightly wound spring like the HD2 kit if I can find a spare one

Thank you for all the input. 1st gearbox lasted such a long time behind a modified engine I hope number 2 gets a good run too.

Looks like I got a few valve body mods to keep doing now. If there is anything else you think I should tackle while it's all apart let me know. I'll probably get it done end of the week due to work commitments.
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Someone should comment on your choice to use the transgo 3-4 and forward clutch springs while keeping the stock 3-4 return springs in the drum instead of not reusing them as the instructions state.

 

I use a tightly wound spring and just clip it with a side cutter to needed length

 

I still think it will help to reduce drag when the clutch packs aren't engaged right. I know it's counter productive to reinstall a set of springs that fight against another set of springs youve modified to be stronger

But. Since you increase the spring tension so much over stock those 5 smaller return springs aren't really fighting you enough to worry about any negative effects.

Even the new Sonnax input drum comes with new ones to install. Must have a benifits. From my experience car manufactures don't add parts (or should I say costs) that have no benifits

 

I do not run those return springs and have yet to smoke a 3-4 clutch pack and set my stack to .030"
I also spin my motor to 7100 ( not 3-4 clutch pack friendly)
and road course my car.

"From my experience car manufactures don't add parts (or should I say costs) that have no benifits"
This is not necessarily true, Quick example would be blocking the 3-2 valve inboard.