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willyman82
03-10-2010, 12:14 PM
Hi All,

I have a 1995 Chevy Corsica with the 3100 and 4t60E transmission.

At highway speeds under even the slightest load like going up a hill it feels like it has no power (TCC still engaged?) then it feels like it might be slipping somewhere then suddenly grabs and goes. There is no tach so I cant really tell very well what the engine is doing. I have read about a lot of different TCC problems with these transmissions (stuck TCC valve, leaking TCC valve, bad TCC solinoid, bad PCM TCC solinoid driver or a bad vacume pressure actuator). Is there anyone with enough expertise to help me differentiate between possible problems? I thought it was the 4 gear clutches so I "shotgunned" a transmission with 51K into the car. I changed a bunch of other stuff while I had the motor out so it wasnt so bad. It was working great for about 2 weeks, but now the same old problem is back, which invalidates all the other work if I cant nail this problem.

Other things that I replaced before doing the transmission were engine position sensors, TPS, FPR, fuel filter, plugs and wires. I have not replaced the MAP and have read that this helps the PCM determine engine load for unlocking the torque converter. I am going to check this out with a DVM and hand-vac this weekend.

Thanks for any help!

3400-95-Modified
03-10-2010, 01:05 PM
If you did have a bad map then I think you would be noticing many more issues... and a 1995 corsi IIRC the TCC stuff goes by throttle position and speed, not engine load.

If you've replaced the entire transmission then I can tell you that the TCC valve, TCC solenoid, the PWM solenoid, and the vac regulator are fine, Unless you swapped all those parts onto the new trans from the old... Which I doubt you did.

Next in line is the converter itself. Did you re-use your original one when you swapped transmissions?

willyman82
03-10-2010, 05:34 PM
Converter, valves and vacuum actuator came with "new" 51K mile transmission. I changed the fluid when I did the transmission. I dont have a flush tool. I just filled it up after the swap, cranked it for about 30 seconds with one of the cooling lines off, topped off, repeat, until I went through 2 gallons of fluid. So the fluid that is in there isnt perfect but it was coming out clean to begin with. I would think that if there was a major issue with the car that it came from, then the original fluid wouldnt be so clean. I did not change the filter. I was going to let it go 3000 miles to the next oil change then do the transmission fluid again after letting it wash through the whole transmission and the filter at that time.

Some more detail:
When I put the shifter into D (assume 3rd gear) the engine revs higher and I can feel when the TCC locks up. It doesnt unlock until well after 1/2 throttle at which point it seems like it is slipping while releasing, almost like a half hearted release. This is the same sensation as when in OD, except I can feel it more because the gear ratio is higher. This shudder happens around 1/4 throttle when in OD. I dont know if this means the valve could be sticking when the PCM is trying to release it or if there is a line pressure problem (holds stronger at high RPM). There are no codes in the computer, but I dont think the computers checked for these types of problems in 95. The trans came from a granny-mobile, so I doubt it ever saw much of the torque converter locking up around town. The torque converter was not discolored or rusted at all. The old one looked like it had been sitting in an annealing oven for 2 years, rusted and discolored. Also, it doesnt stall or even shudder when downshifting or coming to a stop.

I hope the level of detail is more helpful than it is annoying. :confused:

robertisaar
03-10-2010, 06:42 PM
the "slipping release" is exactly what it should do, due to the PWM TCC. it's intended to do just that.

willyman82
03-10-2010, 07:40 PM
The way I understand TCC opperation is that it is supposed to progressively lock up (PWM apply) under light load, then hold until a certain threshold is reached, then it is supposed to just let go under higher load (a hill on the highway). And the problem is that it never actually lets go. I havent confirmed with a meter+test drive yet, but I would bet the computer is still holding the TCC engaged when I feel this pulsing/slipping sensation. When I feel the slipping, I can either let off and it stops (assume TCC remains locked), or press the pedal to the floor then it unlocks and the car actually goes. So it seems that it isnt holding hard enough near the threshold of where the PCM would normally command it to release. The interesting thing that I discovered in today's experiments is that it seems that 3rd gear has a higher power threshold before I encounter the problem, but it still exists. Driving around in 3rd isnt so great for gas milage.

The more I think about it, the more I think the computer may be trying to hold it too long (an attempt to improve milage by GM) or there is an apply line pressure issue.

I found this:

http://www.transmissionpartsusa.com/SC_4T60E_1_transmission_reconditioning_kit_1997_up _p/400-0sc4t60e1.htm

http://www.sonnax.com/instructions/SC-4T60-E-97-IN.pdf

Thanks,
-William

robertisaar
03-10-2010, 07:54 PM
The more I think about it, the more I think the computer may be trying to hold it too long (an attempt to improve milage by GM) or there is an apply line pressure issue.


that notion is pretty relevant to almost all settings in the ECMs made by GM... but the PCM does release the TCC in a PWM fashion, just like TCC lockup, though with that type of slipping/pulsing, it's possible that the convertor itself is toast...

gpse3400
03-10-2010, 10:36 PM
I agree that it could be the converter if you are still using the old one. Another trick you can do, cut the wire for the PWM soleniod and see how it operates then. The apply will be more noticable and the converter should hold harder. If you still have the problem, I would lean on the converter being bad....providing you did not change it prior.

willyman82
03-11-2010, 10:15 AM
I used the "new" 51K miles converter with the trans swap. I tend to think that it isnt the converter, because when its in 3rd the problem doesnt happen until well after 1/2 throttle. So if it was a problem with the converter, I would expect it to slip with the same amount of torque applied from the engine. 4th gear at 1/4 throttle (75MPH) is probably less torque applied than 3rd gear at 1/2 throttle (75MPH).

GPSE3400: Could you please specify which solenoid you are referring to?

I dont understand all of the ins and outs of the trans, but is it correct that the converter will still lock up without the solenoid powered? I thought the solenoid actually drives the valve that locks and unlocks the converter, as opposed to just regulating the operation. This trans has a vacuum cylinder that controls operating pressure instead of a PWM solenoid like newer transmissions.

Thanks,
-William

Edit: One of my friends told me that there are two things in automatic transmissions, ATF and magic. Maybe I just forgot to add the magic back in...

robertisaar
03-11-2010, 10:59 AM
in 3rd with 50% throttle, yeah, more torque, but less load.

the convertor will NOT lock if the TCC solenoid isn't getting power.

payback
03-11-2010, 12:53 PM
ive had identical issues with my 4t60....its possible the TCC solenoid itself is bad, even on the newer tranny. very common.
but im under the impression the valve is stuck, yes the solenoid is supposed to actuate the valve, but if its stuck its stuck.
mine actually threw a code (TCC solenoid lockup stuck on) but mine is obdII.
the problem mysteriously went away but every once in a great while it comes back, but not nearly as bad or as long..which tells me its more of a "somethings stuck" problem rather than an "its bad" problem.

3400-95-Modified
03-11-2010, 01:13 PM
The more common issue that a bad solenoid on a 4t60e is the valve getting stuck itself.

The solenoids go bad on 3t40' but for a 60e, the way to fix this is getting the Shift Correction kit installed, It adds a spring on the return side of the TCC valve, and also makes you chamfer every edge of the valve itself to prevent hang up.

I don't have pics right now of the fix, but I'll be pulling my trans apart soon and I'll show you what they make you do to a stock valve. I will also be replacing the stock one with a Sonnax repair valve, Those have a Teflon seal on them to help prevent any TCC issues later down the road.

I had really bad TCC problems once and the issue that I ended up having was my roll pin that holds my center shaft in my diff snapped off because the outer spiders were galled to the pin... One wheel burns will do that... with a 60e the pin can't fall completely out.. It will sit there spinning around slowly scoring a mark all the way around the outside of the diff housing which in turn spreads aluminum through the motor... in doing that, almost ALL of my valves ended up getting stuck, or started sticking from the aluminum flakes in the oil. It was BAD when I took it apart. I had to replace the valve body completely.

gpse3400
03-11-2010, 05:51 PM
I used the "new" 51K miles converter with the trans swap. I tend to think that it isnt the converter, because when its in 3rd the problem doesnt happen until well after 1/2 throttle. So if it was a problem with the converter, I would expect it to slip with the same amount of torque applied from the engine. 4th gear at 1/4 throttle (75MPH) is probably less torque applied than 3rd gear at 1/2 throttle (75MPH).

GPSE3400: Could you please specify which solenoid you are referring to?

I dont understand all of the ins and outs of the trans, but is it correct that the converter will still lock up without the solenoid powered? I thought the solenoid actually drives the valve that locks and unlocks the converter, as opposed to just regulating the operation. This trans has a vacuum cylinder that controls operating pressure instead of a PWM solenoid like newer transmissions.

Thanks,
-William



Edit: One of my friends told me that there are two things in automatic transmissions, ATF and magic. Maybe I just forgot to add the magic back in...

The PWM Soleniod for the TCC flakes out very often on the older transmissions. when it does it can cause the TCC to engage poorly or not at all. By disconnecting it the main TCC soleniod will have controll over the circuit. I'm not sure what wire it is, you will need to get a wiring diagram. Just cut the wire or remove the pin and drive the car. The problem should go away. Keep in mind the TCC will engage more noticably.

robertisaar
03-11-2010, 06:07 PM
this should help with the wiring... brown wire in the tranny connector. and if you can happen to see the lettering on the connector, it's position C.

if you need the diagram for the plug itself, i'll have to upload that too...

willyman82
03-12-2010, 08:44 AM
This is all good info. One thing that is still conflicting is whether or not the TCC will lock up if I cut the connection to the TCC solenoid. I was under the impression that it will NOT lock up if power is cut. The wiring diagram that I have shows that the power for the TCC solenoid comes from a switch on the brake pedal that is intended to shut it off when stopping. This would imply that cutting any wires will cause the TCC to not lock up. The diagram that robertisaar uploaded doesnt align with the diagram I have for my 95. Maybe later 4t60e's had more stuff in them? My diagram shows only 3 solenoids with no temperature sensor. I measured to all of the pins on the connector of the old transmission. I get 48 ohms between two circuits with a common pin (suspect these two are the shift solenoids). Then 10 ohms between two other independent pins. I suspect this is the TCC solenoid. All other pins appear to be open circuits on the old transmission. I still have to test the new one to see if I get the same results. Does anyone know what these resistances are supposed to be?

The "new" trans came from a car with 51K that was a 95 Cutlass I think... There is no way the donor car saw a lot of highway time with the TCC locked, so I am struggling with the concept of how anything could have worn out related to the TCC hydrolic circuit.

More testing will happen this weekend...

3400-95-Modified
03-12-2010, 09:25 AM
The TCC locks up ALL THE TIME, not just on the highway so its not uncommon for it to wear out even if driven by a g-ma. Its more the act of town driving and 45-50mph where its locking and then unlocking... At least its like that in my area because we have lots of hills.

95 4t60e's had the temp sensor as well. I have a 94 trans in my 95 beretta thats run by a 97 venture ECM and I can read a trans temp value, and I've seen it with my own eyes.

robertisaar
03-12-2010, 10:20 AM
just like clutches, lock/unlock, engage/release: every time it does it, it wears it out a little more, and eventually it will fail. granted ~50K miles isn't that much, but who knows how those miles were driven.

EDIT: and removing the PWM wire from the equation will just only allow 100% apply or 100% release, nowhere in between. it's strange that GM decided to use two circuits here, but it works. when the PWM solenoid hits 100%, the on/off solenoid goes on and the PWM probably turns off(i haven't had a need to deteremine if it does or not). and then when it's time for release, the solenoid would power to 100%, the on/off would go off, and the PWM would dial down to 0%.

at least that's what i'm being told from alldata.

willyman82
03-12-2010, 02:11 PM
Ive just been visiting all-data also. I understand now what you are saying about cutting the PWM wire. I may do this and see what happens this weekend. A hard lockup and hard unlock may not be so bad to eak out another 50K from this F'in car. Just a bit uncomfortable for the driver to get slamed around. Just so Im straight on this, the ECM modulates the PWM valve to control the presure to the lockup plate in the torque converter, and the other solinoid is just on/off? So the car will remain drivable and wont stall at lights, etc?

robertisaar
03-12-2010, 03:36 PM
more or less, that's exactly how i would explain it.

gpse3400
03-13-2010, 09:36 AM
Ive just been visiting all-data also. I understand now what you are saying about cutting the PWM wire. I may do this and see what happens this weekend. A hard lockup and hard unlock may not be so bad to eak out another 50K from this F'in car. Just a bit uncomfortable for the driver to get slamed around. Just so Im straight on this, the ECM modulates the PWM valve to control the presure to the lockup plate in the torque converter, and the other solinoid is just on/off? So the car will remain drivable and wont stall at lights, etc?

Its not that bad. But ultimately If you do find it that harsh, you might be able to reign it in with an adjustable modulator if you don't already have one. But as a result, your normall shifting might get alittle mushy.

willyman82
03-15-2010, 09:25 AM
This weekend was a bit of a washout because of the rain, but I got some tests done. The solenoids are 22-23 ohms for 1-2, 2-3, TCC and 12 ohms for the TCC PWM solenoid. Temp sensor is about 2K warm and about 7K cold. The vacuum actuator works and gets the same vacuum as I measure at the direct manifold tap (17 inches Hg). I get 11.8V at the common supply to the connector with the engine off and key on.

I clipped the TCC PWM solenoid wire. The lock/unlock feel is much more defined, but it doesnt hold any better than before. The judder is the same as it was when I encounter a small hill on the highway. It seems unlikely that the TCC would be bad from a 51K trans, but I guess its possible. I sure don’t want to pull trans again if that is the case. I think clipping the PWM wire rules out issues with the computer not applying enough pressure to the TCC. Other opinions on that?

Once the weather clears I am going to do a line pressure check using the tap on the top of the trans to see if it is low. I may even run a long piece of brake line into the car to watch the gauge as Im driving and the TCC locks up. Next Ill drop the pan and check the filter. This may sound dumb, but I figured I would do the filter after driving the new trans for a few thousand miles to wash any stuff through so as not to foul up a new filter right away. Wouldn’t the pump make a lot of noise if it was having trouble pulling fluid?

I already pulled the end off the old trans and it doesnt look like a valve body job on this thing would be so bad. Ill just pull the whole driverside suspension and K frame, lower the engine and pull the brain bowl off. Has anyone else done this before?

Thanks,
-William

3400-95-Modified
03-15-2010, 10:43 AM
It's not that hard, but you need to catch all the ball bearings that are between the VB and the Channel plate, and put them back where they belong ;)

I would suggest getting a ATSG Book before pulling the VB off, and if your going that far I would also suggest doing the Transgo shift correction kit. It's a $40 kit and worth it to prevent this again.

I just dropped 230 on valves and such for my trans this year, and thats already got the Trans-Go kit.

willyman82
03-15-2010, 10:48 AM
Is this the kit? If not, could you please provide the link.
http://www.sonnax.com/instructions/SC-4T60-E-97-IN.pdf

I already have the book on order. What is the correct type of grease to use to hold the check balls in place for re-assembly? I have read everything from bulb grease to petrolium gelly and axle grease. Axle grease seems wrong because I would think that would dammage the clutches.

3400-95-Modified
03-15-2010, 11:03 AM
I use Trans assy lube, its a green grease that dissolves with transmission fluid.

That would be the wrong kit since its 97 and up, you want this one.

http://www.transmissionpartsusa.com/TRANSGO_4T60E_Shift_kit_1991_99_p/500-000037936.htm

and you want the assy goo thats on this page. I use the green, but I guess the blue is good too.
http://www.transmissionpartsusa.com/Lubegard_Fluid_Additives_s/6351.htm

You can also buy a new TCC valve from TPA if you wish. I just did, They offer it in reamed size if your bore was destroyed and you have a ream tool, OR just the stock size to help prevent side loading and sticking.

also the SC kits are much more in-depth And require tool kits to install... so the kit is $123, and then the tools are $104. Probably only needed if the trans is worn really bad.

willyman82
03-18-2010, 09:54 AM
Hi All,
I have been studying the hydraulic circuits in the manual for this trans. I think there might be a leak at the TCC apply valve between the 2nd feed circuit and the exhaust port (top of the valve). This would explain a weak lockup and eventually no lockup (as was the case with the last transmission). In comparing all the differential pressures in the valve body, this point has the highest differential pressure and therefore would be the most likely to fail. Also, it is the narrowest so any leak past the seal would not be slowed by boundary condition turbulence as it would in the other valves. The leak could certainly be elsewhere, but this reeks of a bad design and is highly suspect. My fiance has decreed that I wont be taking the valve body apart until I can prove my theory by taking apart the old trans valve body and examining the TCC control valve seal...in the summer. Since I need a car before then I did a few experiments.

First experiment: I disconnected the vacuum regulator on the side of the trans to command max hydraulic pressure. Oh boy shifts are firm! TCC seems to hold a bit harder in OD but still shudders on hills.

Second experiment: I disconnected the PWM solenoid for the TCC with the vacuum regulator still disconnected. This gives max feed pressure to Apply circuit and the valve will stroke further because the 2nd circuit has higher pressure than before. I was unable to recreate the shudder problem with these two changes.

Obviously the car still is not drivable like this, so I came up with a circuit that does two things. When in 4th gear as commanded by the PCM (Sol A - ON / Sol B - OFF) and the TCC solenoid is turned on, a circuit will enable a vacuum control valve on the vacuum modulator (vent modulator vacuum to atmosphere) and disable the PWM solenoid. So when on the highway and the PCM commands the TCC to lockup, it will go to max pressure with no PWM control of the TCC. Otherwise it will drive like normal around town and still have PWM TCC control when in 3rd.

Can anyone find a fault with this as a temporary fix? Could anything be damaged by running continuously at maximum pressure (not shifting just constant)? Is there any chance of blowing something apart internally or can the trans handle this?

Thanks,
-William

3400-95-Modified
03-19-2010, 09:00 AM
Hi All,
I have been studying the hydraulic circuits in the manual for this trans. I think there might be a leak at the TCC apply valve between the 2nd feed circuit and the exhaust port (top of the valve)

This is probably why they have come out with this valve to fix it. I ordered this along with the anti stick 1-2 2-3 3-4 and the 4-3 3-2 valves... and line pressure boost vavles and such. Same as I did with my first trans and I really liked the shifts after doing that.

http://www.transmissionpartsusa.com/v/vspfiles/photos/400-08475422K-2.jpg

The new TCC valves sold to replace the fully steel ones have a teflon seal at the end.

Unless this is not the area you are speaking of.

willyman82
03-19-2010, 10:38 AM
3400-95-Modified: Did you increase your line pressure by changing the regulator springs? If so what did you increase it to? Im trying to get an idea of what the trans can handle...

That valve is exactly what I am talking about. Problem is my fiance wont let me do a valve body rebuild until the summer when the weather is better and we have more time. I already did the trans swap and that took way longer than it should have because I threw out my back doing it.

NEWS! I verified that the old transmission is code WFW and the new one is a WFW also. Phew! Now I just need to make it work until I can fix the valve body. I dont know much about GM platforms, but the Acheiva (donor) was a type N and my Corsica is a type L from what I can gather. The WFW only went in those two types. Other 3100 drivetrains with the 4T60E in other platforms got different transmission codes.

Thanks,
-William

3400-95-Modified
03-19-2010, 11:54 AM
I've used up to 99 buick transmissions in Beretta's... The only change is the final drive, the torque converter and a few internal hard part upgrades. So having an exact WFW is not necessary, but does make it easier. To make a newer 99 one work, I've had to swap the side cover, and the tone ring on the differential to keep the speedo right. This works on 94-95's since they use speed to shift, on a 96 it will throw a code unless you fix the gear ratio multipler telling it your are running a 1:1 chain vs the .89:1

I am usng the adjustable vac modulator for upping the line pressure some, and I also shimmed my accumulator springs to put more preload on that. I don't have the tools to check the line pressure so I am not sure how high it is... I know its no where near pegged or at the limit. I will typically adjust it and keep my eye on the trans temp to ensure I'm not stressing the pump and generating a bunch of heat... As of right now I think it was staying under 190*f driving around town... I do not live in a city so I do not know how it would respond under those conditions.

I'll be posting pictures soon in my Performance 4t60e thread showing whats coming out of my car as well as what I'm putting in it. I'm going to be tearing into it tonight and I hope to get all the valves that I ordered this week.

Here is the list of valves that I bought from TPUSA

IsaacHayes
03-19-2010, 12:42 PM
Willy, have you already built the circuit? Could you post the diagram if you have drawn one out? Sounds interesting. If you do run a solenoid to vent the modulator, make sure there is a check valve before the vent so it doesn't create a vacuum leak and possibly a filter on it to keep dirt from going into the modulator/engine.

If you have a laptop and an ALDL cable, I have a TunerPro RT definition to scan the 94-95 V6/4T60-e engines. You can see TCC slippage, trans temp, etc etc. and log and datalog it in real time...

I believe the trans is also controlled based on MAP load too.

robertisaar
03-19-2010, 12:47 PM
I believe the trans is also controlled based on MAP load too.

there is a way to test that....;)

you'll run a bit rich though.

3400-95-Modified
03-19-2010, 01:04 PM
I believe the trans is also controlled based on MAP load too.

In what regard?

Pressure is controlled ONLY by engine vac and the vac modulator... The rest is electronic shift control.

Are you referring to shift logic and TCC lock up and unlock procedures?

IsaacHayes
03-19-2010, 01:15 PM
Yeah, the shift and TCC control uses MAP input I believe. I was not referring to line pressure.

I've gone up hills before and before I can tell or the speedometer is registering I'm going slower the TCC unlocks as the engine becomes more bogged sounding. Tach really isn't changing either.

3400-95-Modified
03-19-2010, 02:25 PM
TCC uses throttle % vs MPH to determine when to lock and unlock. There is no MAP info used. At least not in any tables that I can edit in a 96 and 97 ecm... I have no idea how a 94-95 OBDI.5 does it. Hell they dont even use RPM as a "critical" shift function.

willyman82
03-19-2010, 03:47 PM
Modified: I am using a 1/8 inch NPT thread to hardline fitting to connect the trans pressure tap to a 1/4 copper tube. I checked the thread on the old trans and it goes in more than 5 turns by hand. Its not a perfect fit and will probably leak a bit, but I am running this to another fitting that I hooked up to my compression tester that goes up to 300psi. I will post a video on Youtube in the next few days. I bought enough tube to snake inside the car, but havent tried that yet. If I do Ill take some more video and edit it all together.

I will post a circuit schematic of the temporary fix for this once it is done, tested and working.

Thanks,
-William

willyman82
03-19-2010, 07:06 PM
Test Drive Results:

1) Control (PWM sol and vacuum modulator hooked up) Torque converter shudder is experianced almost as soon as the throttle gets past 10%. Anything but driving straight and level at 70mph causes it to shudder. Line pressure is about 100psi when shudder starts.

2) TCC PWM solenoid disconnected yeilds a higher throttle position threshold before shudder is experianced. Higher throttle input causes the PCM to unlock the converter and all is well. Line pressure is around 150psi before being unlocked with shudder occuring and about 160psi after being locked up with 1/2 throttle.

3) Vacuum vent solenoid enabled yeilds higher opperating pressure as expected. 160psi at idle in OD and about 180psi on the highway at 70mph. TCC shudder is experienced just before the threshold of the ECM unlocking the torque converter at about 1/3 throttle. Pressure doesnt seem to want to go much past 180 when in drive (160 -180 depending on RPM). I suspect this is due to various blow off valves throughout the hydrolic valve body venting the excess pressure at 180psi.

4) Park pressure with vacuum actuator disconnected is over 200psi! Shifting into drive or reverse gives quite a jolt.

So based on all this data, I think the car would be perfectly drivable without signifigantly increasing line pressure if my proposed hack solution is implemented (increase line pressure and disable PWM sol when in 4th with TCC commanded from PCM). As soon as I am done and have tested the results, I will post schematics, diagrams and video links.

A funny side note is you can really hear the transmission pump LOUD inside the car with a spool of copper tubing filled with pressurized transmission fluid. I also got a very funny look from a cop that I passed heading back to the house with wires and 1/4 copper tubing snaked out the passenger window and under the hood :-)

-William

willyman82
03-31-2010, 08:13 AM
Sorry that I havent posted any of the videos yet. I just havent had time to edit and upload them to utube.

I pulled the old trans valve body / channel plate / pump housing assembly off last night and found several things that were interesting.

The first thing I noticed was that all the bolts around the assembly were different torques. Some seemed way too tight and some were almost loose. I didnt think anything of it at first since they are all different lengths, but then I found more weird things. The TCC solenoid had a small O-ring stuffed in the small bore of the solenoid itself. I cant imagine where this could have come from inside the transmission, so I suspect it was put there intentionally (not by GM). The valve itself is actually steel!?!? It was sticking in the bore, so I couldnt get it out by using the return spring shoot it out. I ended up using a magnet as soon as I realized it was steel. It is not the sonnex valve with the teflon seal, but it is not the aluminum valve I was expecting either.

Has anyone ever pulled apart a 4T60E and found a steel TCC valve? Is it safe to assume that the original trans (262,000 miles) had been rebuilt before I bought the car at 100,000 miles? Maybe that is why it made it to 262K...

More to come as I get to upload videos and pictures and get further into the original valve body.

Thanks,
-William

3400-95-Modified
03-31-2010, 10:14 AM
Measure the valve... Unless they changed in 96 and went to aluminum from the steel it should have been aluminum. Also with the O-Ring, there should be one on the TCC solenoid itself, but not in the bore between the valve and the solenoid if thats what you mean.

Also yes all of the VB bolts will be torqued differently... Check the book they are different depending on what size bolt they are.

Get pics of the spacer plate, and I can tell you if they put the trans go kit in it before... Also how bad was the valve sticking?

I have to go back and look at my pics of my other trans I did, but IIRC the original TCC was aluminum, and the one that I got with the new VB I bought was a purple anodized one since it was the oversized version that was put into that setup.

Actually I think I still have that valve body at home from the old trans... so I should have a 94 to compare.

willyman82
03-31-2010, 10:55 AM
I will get pictures sometime this weekend. I doubt that I will have time to dig it apart before then. I can measure the TCC valve tonight. Just to make sure everything stays clear, this is a 95 vehicle with the WFW 4T60E varient.

There is 1 O-ring on each solenoid, except the PWM which has two. The TCC control solenoid had a 2-3mm ID O-ring stuffed in the hole in the middle of it. Could this have come from the TCC-SIG orfaced flow regulator? From the diagrams that is the only thing up the line from the TCC control solenoid. It doesnt look like anything could get past that from the pictures in the book. I havent actually seen it yet though. The only thing I can think of is that a transmission tech stuffed this in there during a rebuild to restrict flow through the solenoid for some reason. I dont see how this would do anything if the solenoid valve wasnt working properly. If anything it would cause the TCC to be lightly engaged all the time.

When I pushed the valve in from it's parked position it moved freely, but on a slow rebound I could feel something hanging up just slightly. When I tried your trick of letting go fast to shoot the valve out of the bore it just stopped when it hit the lip of the TCC-SIG orface. After trying a few times I realized it sounded funny when my screwdriver was making contact with the valve and thought it might be steel. So I tried my magnet and was able to pull it out without too much effort.

Thanks,
-William

3400-95-Modified
03-31-2010, 12:14 PM
I've never seen an O-ring on the ID of the solenoid... Thats really odd...

and yes I would be looking at a similar trans, the valve bodies were all the same for 93 to 99 (may have just use different material valves) as far as I know. And I may actually have a 95 VB at home... i think the 94 one I did use before ended up going back as a core to someone, or maybe I just have both... lol