Monthly Archives: October 2011

4L60E Valve Body

the main difference between the 700R4 and the 4L60E is the valve body in my opinion. unlike the older transmissions….and very similar in the scheme of things to the 4l80e and other modern trannys, the valve body is constructed out of aluminum instead of iron and is computer controlled. the valving seems somewhat elaborate but to be honest, there are only a few areas you really need to concentrate on while servicing these valve bodies. the ATSG and the aftermarket performance  manual i bought on these trannys left a bit to be desired, and of all things i had to spend quite a while digging around to come up with a version of servicing these valve bodies that makes sense. one builder will tell you the whole damn thing has to come apart……..another builder says replace the force motor- clean it-say piss on it…….yet others replace the seal in the accumulator and buy a new mid plate! so, figuring that i write a lot of this for the do- it -your-selfer, i am going to attempt to guide you through one as simple as possible.

like i mentioned in my previous article about the front pump, the achilles heal of these trannys is the extreme wear of the valve body because it’s made of aluminum, although for the most part the valving is not steel. while some valves wear excessively- others do not.   have an ATSG manual handy for referrence. 

S3700072First thing to do is to remove the forward accumulator. there is a lot of tension behind this cover so when you remove the small screws take note. there will be two springs and a piston underneath the cover. the larger one is for the accumulator and there are different ones for different applications. the piston can be either plastic or aluminum. to the right of the piston under the cover is the low overrun valveand spring. remove and set it aside…..below that is yet another valve in the same passage…..this is you forward abuse valve. and this is one of the points you will have to check later. S3700056there is a doweled plug in this passage holding the abuse valve and spring in. i am pointing to the dowel in the photo. this same style retainer is used in a few other valves in the body as well. simply remove the dowel and the valve comes out. back to the picture above…..to the right of the accumulator cover are your two shift solenoids, A and B. the computer uses these solenoids to fire off the different gears. they can be checked using 12 volts and you will also need to make sure the ends of em are clean of debris. valve A has some spring tension whereas valve B does not. it is no where near as much tension as the accumulator. the valving below these 2 solenoids can be ramoved as well and set aside if you chose to, and is not a bad idea but can be time consuming and frustrating. coax em out with a small screwdriver but do not slam the valve body on the bench to get em out! you will fuck up your valve body and be in deep shit. remember it is aluminum……also remember it has sharp edges and will cut your hands nicely.

next to come out is our force motor. this is removed via a clamp and a bolt. there is no way to check this with 12 volts so you should shit can it and buy a new one during a rebuild. S3700067if for some stupid reason you need to re-use it, be sure to clean the screen at the end as it will fill with debris. below the force motor is the valving for it. it is removed by pulling a clip out the top of the valve body….similar to the two shift solenoids. the clips can fly off to neverland…….and the plug, spring, and valve can take flight as well so be aware. this valve is called the actuator feed limit valve.

the last thing that has to be removed is the 3-2 downshift solenoid. 1996 and newer used and on/off type solenoid that can be checked with 12 volts. older, earlier models used a pulse width modulated solenoid that is a throw away cause you can’t check it. sometimes the 3-2 solenoid has already been removed during main disassembly so you could get the TCC solenoid out of the pump. basically it’s a plug-spring-and valve below the solenoid if you chose to remove em.

with all electrical removed from the valve body, you need to clean the valve body with solvent and dry it. the two spots you have to concentrate on for excessive wear are the forward abuse valve and the actuator feed limit valve below that force motorS3700063(the one you throw away and replace). these two have to come out and get checked. with a clean valve body, shove the abuse valve in the body and shine a flashlight down from the top while looking down in the port. if you see a shit ton of light resembling the moon……it will leak and needs to be repaired. if you see very little light, then it will be fine. it is impossible to check this with oil on the parts as they will fill the gap….so it all has to be dry and clean to see the wear.

 

theS3700069 actuator feed limit valve needs to be checked in the same manor, except there is a problem the part you need to check is blocked by the outside of the valve. my index finger is pointing to the front of the valve and middle finger pointed to the wear point you need to check. to make this check, i basically found another valve and cut the end off it so i could see the light…..so to speak. the force motor replaces both the vacuum modulator and governor found on the older trannys and is the main component the comuter uses to control fluid pressure…..it motions several times per second like an electronic fuel injector and needs to be adressed above any other component in the valve body.

Sonnax makes oversized valves/tooling for both of these valves….as well as other valves throughout the valve body. the stuff is expensive. if you aren’t planning on doing a whole hell of a lot of these and need these fixed, try and find a local tranny shop to fix it for ya with their tooling or bite the bullet and buy a new valve body. now i have to admit , i only remove the solenoids and these two valves first. if both of these valves look good, i will stick a pocket screwdriver in the rest of the valves to make sure they move and the springs are working, check my solenoids, and put the damn thing back together with a new force motor/pulse width modulator. if they aren’t worn in these two areas…..more than likely the rest is alright.

the last thing to check isS3700062 the pressure switch assembly. this is the view from the top side and in the picture  S3700061to the left, i am pointing to the oil temperature sensor. the switch assembly here has  5 ports that need to be checked. 3 of them are normally open and two are normally closed. basically you take an ohm meter and check them for function by pressing the center of the switch with a small punch. these are simply on-off switches so if you have a continuity noise maker on your ohm meter that’s all you are looking for. there is also a resistance per temperature spec for the oil temperature sensor. this piece is basically what the computer uses to monitor what the hell the tranny is doing. basically if what this thing tells the computer to do:doesn’t match what the computer is tellling it what to do: it sets off that wonderful idiot light on the dash and creates drivreability issues. both of these tests are outlined in your ATSG manual.

4r70w/4r70e improvements

 ok guys, i did not write this i found it elsewhere, so credit should go to whoever did the research on this one. i can’t remember where i found it originally several months ago. basically it describes the upgrades in the early 00’s of the ford 4R70 and4R75  automatic transmissions found in most crown vic style cars. i saved it for my own referrence and figured some of ya might like to read it too………..

 

 For those unfamiliar, somewhere along the way FORD started to standardize their naming of transmissions. The first number (4 in the case of 4R70W) stands for the number of forward gears. the R stands for rear wheel drive, the 70 (or 75) is torque handling capability [add a zero at the end and you have the torque capacity in foot lbs – 70 = 700, 75 = 750] and then the W in the case of the 4R70W stands for Wide ratio gearing. Initially FORD used an E on the new all electronic versions of older trannies when they were introduced (AXODE AODE 5R55E etc). The return to a 4R70E and 4R75E is still somewhat a mystery, unless it was designed to denominate a standard gearing ratio tranny as opposed to the wide ratio 4R70W. But I digress…

In 2004 the venerable 4R70W got some significant changes made to it. Remember the 4R70W traces it’s lineage to the AOD, which has been around nearly 30 years. the 4R70W was born in 1996 from the AODE. Significant changes occurred in 1998, and some smaller ones since, but nothing like this.

The changes are as follows:

1. redesigned pump and stator assembly
2. redesigned intermediate clutch assembly
3. redesigned forward-clutch drum (with a new Sun shell as well)
4. redesigned center support
5. new style anti clunk spring (now called an anti rattle clip)
6. redesigned transmission case
7. shorter output shaft speed sensor
8. redesigned ring gear

FORD says none of these parts are reverse compatible. While I understand what they say, I do know that in the past they have said that and ingenuious folks have found ways to work around and MAKE them reverse compatible. Still, at this juncture I’ll take them at their word.

One of the interesting things about redesigns by the manufacturer is that they highlight problem areas – usually already well known and with existing aftermarket fixes.

Here is what we know about the 4R70W in terms of weak areas. The pump sealing rings have been a minor problem area and often that has led to problems in the forward clutch area due to inadequate pressure. Aftermarket one piece teflon seals have appeared in an effort to solve this. Also drilling the feed hole to the forward clutch circuit is also not uncommon. The direct drum had similar issues with scarf cut type sealing rings on the output shaft feed, and that was fixed in the aftermarket by adding one piece sealing rings (which FORD even includes now in their rebuild kits as well.) The intermediate clutch was not a problem area to my current knowledge, but FORD has upped the size of the apply piston in their upgrades.

Let’s look at the upgrades one by one.

1. Intermediate piston

The old intermediate piston design had a piston that was .550 inch wide and that used lip seals. The new one is .690 wide and has a bonded seal. The old piston had a bleed hole, and the new one uses a checkball capsule. The old spring retainer has been eliminated, and in its place there is a case mounted wave spring used as a return spring.

2. Pump

The pump stator has a deeper sealing ring groove and FORD has gone to a plastic butt cut sealing ring. The pump body was redesigned to accomodate the larger piston for the intermediate clutch and elimination of the return spring assembly.

3. Forward Drum

The forward drum was changed to provide a triggerring mechanism for a new speed sensor.

4. Sun Shell

The sun shell was changed from a ferrous material to aluminum to allow operation of the forward clutch sensor. This meant using some rivets to retain the shell to the sun gear (I openly wonder the strength of this setup).

5. Center Support

The center support has yet another notch cut in it to accomodate the new speed sensor. In 2002, FORD apparently eliminated the old style “clock spring” anti klunk spring in favor of a new style “clip” looking thing. I plan to investigate the reverse compatability as I HATE the old style. For those interested the new style is FORD P/N 2L3Z-7F277-AA.

6. Output Shaft Speed Sensor

The old output shaft speed sensor was made .100 shorter, and instead of triggerring off the holes in the ring gear, it now triggers off the parking pawl teeth, which have been made longer. I suspect the days of ruining the output shaft sensor on disassembly are now gone.

7. Case

Finally, the case has been slightly redesigned to accomodate the added sensor (turbine shaft speed sensor) on the forward drum.

I do not know exactly how the 70 became a 75, but someone earlier claimed there was a running part change in the planetary assembly that they attributed the increase in torque handling to.

700R4/4L60/4L60E Front Pump Service

 Fundamentally, all automatic transmissions use the front pump simply as a hydraulic pump. it’s like a farm tractor uses a pump to run implements by supplying oil to the control valves- then to components to create a function. on a tranny we use the outer shell of the torque converter to drive the pump- then send the oil to control valves that dictate what comp0nents need to be fired off to create function.

On these transmissions,as well as the 4L80E, this is where they really set themselves apart from the older generations of trannys like the th350 and th400.S3700012 the older trannys used a gear type pump sandwiched between two  iron halves. they are known for wearing the gears into the pump halves creating internal leakage and loss of pressure. the end play is also adjustable via the washer at the back side of the pump around the stator hub. here in the picture is a newer style hydraulic pump made of aluminum. the thrust washer on these is not the adjustment however- the adjustment for end play is on the front of the input drum. they also switched to a vane style hydraulic pump over a gear type pump.  it also contains two of the control valve assemblies: the pressure regulator assembly and the torque converter clutch valve assembly.

there are several vanedifferent pumps and combinations throughout the years, so here again unlike the older trannys, the pumps cannot necessarily  be swapped around and are year specific to an extent. early 700R4 pumps ad a different size stator and smaller input shaft….and are considered undesirable. in the mid 80’s they beefed up the input shaft. early 700R4’s up to around 1987 also used a 7 blade vane pump. they are known for failure and also had an outer slide that was a fail point. later models beefed this up to a 10 vane pump and a hardened outer slide ring. later years of the 4L60E used a 13 vane pump. now, this was primarily done to smooth out oil flow for a more consistent output: better driveability. they all put out the same amount of oil flow. a 7 blade pump is considered obsolete if you ask me and if it were me , i would replace it with a 10 vane pump and ring set up. a 13 vane set up is kind of like 10 lbs of shit in a 5 lb bag. under high hp applications it can crack. so to me, if you have a 7 blade pump, i would upgrade to a 10 blade. if i have a 13 vane pump: if it is in good shape i would re-use it. a 10 vane i would simply check it for wear. at the very least if you want to re-use a 7 vane pump buy a new outer slide ring. also when switching around pumps, remember there are different witdth’s of pumps and cover halves- so be year specific. the wrong pump in the wrong half and you will be in deep shit!

there are a few seals for the gears in these pumps and are supplied in an overhaul seal kit. vanes can be replaced individually for wear. the front pumps of these are also known for the front seal comming out. early model 700’s are known for this and GM came up with a retaining ring that fits over the seal. if you don’t have one of these  on the tranny you’re working on they can be had cheap(scrap yard core pile) and are not a bad idea.  i have heard of guys drilling the drainback hole out larger in the pump cover to prevent the seal blowing out…..not for me i guess. also it is worth noting that newer style 4L60E pumps have a different converter support bushing in the front and some builders feel they are better. if necessary to replace a bushing, if it needs to be staked in place do it. the bushing will walk out of the front of the pump and take out the seal.

aside from inspection of the pump, the other areas you need to deal with in the stator shaft pump_valves_lineupcover/rear cover are the two valve passages. both the pressure regulator valve and the TCC valves are steel….in aluminum bores…..yeah it is a high wear area and MUST be checked. pictured here is the regulator valve and TCC valve locations, along with a referrence to modifications described later in this article.

 if there is a lot of slop around either valve……when you get hot weather and that fluid gets hot…..all sorts of goofy shit will start to happen. on the regulator valve it will basically lose optimum system pressure and cause all sorts of long term damage from slipping bands and clutches…..especially after you get a trailer full of scrap behind the truck on a nice july day. same thing with the TCC valve- good hot oil and you have oil leakage- the Torque converter will lock and unlock- slip. it will feel like you are riding on a bull if it gets extreme enough.both of these problems as odd as it may seem- may go away in the fall and winter. thicker oil and it won’t leak- or a can of lucas oil.

to be honest, checking the wear on these valves is a pain in the ass. i remove them- clean the housing real good and stick the valves back in the bores dry. if they seem real sloppy they need repair. Sonnax makes repair kits for both of these valves. you basically ream out the passage and install an oversize valve. the tooling is expensive as hell, it is usually cheaper just to buy a brand new pump or at least a new stator half than it is to repair the passages. so make sure you don’t have to repair these valve passages BEFORE you order pump parts for the vane pump. it will be cheaper to buy the whole damn thing. also on the regulator valve, there is a land you must either grind off or buy aftermarket. it is a service bulletin from the mid 90’s from what i can gather and is in the ATSG manual. it’s pretty simple. it is to improve lubrication and reduce pump fluttery noise that can occur.also i found referrence to also modifying a land on the TCC valve and changing the spring….also listed in the picture above, but they ARE NOT described in the ATSG manual, so all i can say is if you chose to do what is in the picture it is at your own risk, consult your tech manual and/or valve body kit you may be using.

the pressure regulator also contains the reverse boost valve and the throttle valve boost valve, or TV boost valve.boost the TV boost valve was also a problem area of these older trannys, and there are several different sizes available. as a rule of thumb, i always install a .500″ diameter boost valve. in the picture it is the one on the left and is the first one to come out of the regulator passage after removing the retaining clip. the larger diameter boost valve allows the throttle valve to ramp up pressure quicker for a better clutch apply. some builders prefer a .471 diameter over the .500″ diameter for driveability reasons. i prefer the .500″ simply because i rather have a stout shift than a burned up tranny in 6 months.

now i know iS3700041 have missed a few things here, cause there is a check ball, orfices, and what not, but i hope it gave you some idea of the major things to address on one of these new style pumps. also don’t forget to replace this straining screen. it keeps the shit out of the the TCC circuit i think. if it plugs it will do all sorts of goofy shit too……but if it is plugged the it is probably from stuff elsewhere that failed anyways. don’t forget to replace it. you get one of these in the overhaul kit too.

Torque Converter Clutch Hot Wiring

Well  to answer a few questions i have gottenon a 700R4( and 2004R) , they obviously have what is called an internal torque converter clutch, or TCC for short). as i have gone over before, it is basically a wet clutch applied by the transmission to lock up a torque converter for mileage. it is usually engaged by the computer control from the factory. now, there 700R4’s that had lock up internally in the transmission without any external computer control. gm actually originally designed the valve body for this, then quickly converted it to computer control primarily for emissions/mileage reasons. most 700r4’s have aluminum plugs in the valve body where the original tcc valve would have gone. you can retro-fit the valve body with aftermarket parts to do this as well. i have never done one or ran across one yet, but i know it can be done.

BUT,  we are all cheap bastards, so usually what is going on now-a-days is swapping these older overdrive trannys into street rods and plow trucks for mileage…..or we simply had a working tranny laying around from an old derby car we gutted and th350/400’s are getting hard to find.

So, when doing a swap into another vehicle, the only real critical thing you need to worry about is adjusting and installing the throttle valve cable correctly. the electrical connector for the TCC can be left unhooked.  OR if having one rebuilt, you can simply install a cheap kit into the pump and omit the clutch all together…..which is what i did. however this causes you to lose some efficiency and mileage due to the converter slippage.

to be honest even though it has a 4 prong connector hanging out of the case, the actual engagement of the TCC solenoid is a 2 wire solenoid with one grounded and one 12v power source. GM used several different wiring formats throughout the years some using as many as 4 pressure switches …….some only one. this is because gm was trying to lock up the converter in more than one gear…..which probably led to pre-mature tranny failure.

the way i wire it up it to basically drop the pan, rip the 4 pin connector out of the case and install as single wire kickdown plug from a th400, then run a single power wire from the 1 pin th400 connector to one side of the TCC solenoid. now, the other wire off the solenoid is ground. i then use a pressure switch in the 4th gear passage  on the valve body as a ground. there is usually one there anyway, but you should make sure you got the right one.

this way no matter what you do for power, the TCC will only engage in overdrive. you can run the ground wire off the TCC solenoid straight to ground but if you forget to shut off the switch, it will stall out the engine and scare the shit outta ya. i would either use the ground switch or leave the tcc unhooked all together.

now, if you have any idea what i am talking about by now, you can figure out that you could just wire the damn TCC to a toggle switch  on the dash and lock it up whenever you want. by using a psi switch in the 4th gear port, you basically can flip the switch for highway driving and as soon as it hits 4th gear you got lock-up. for in-town/city driving you can leave the switch off pretty much cause a TCC doesn’t doo much good on these trannys in heavy traffic anyways other than tear up the tranny faster.

the pressure psi switchswitch you want to wire to is the one marked letter “A”. this is the 4th gear pressure port. GM used both normally open and normally closed switches….both single and 2 pronged. i like to use a single prong normally open/psi closed switch. i believe the GM part number is GM#8627332 . now some valve bodies didn’t use and psi switches at all and simply have 1/8″ pipe plugs. if you decide to do this, you can omit the rest of the psi switches and replace em with pipe plugs to save confusion later on. you can also modify your wiring and make whatever switch you have on your valve body work to engage the TCC only in 4th gear.

 

here is a rather wiring tcc terrible drawing of how the wiring goes. the red obviously is 12v and the blue is ground to the 4th gear psi switch.

 

 

 

 

 

now, if you do not like the idea of just using a toggle switch , or the driveability using a toggle switch isn’t to your liking,  you can then take the 12 wire and instead of wiring it to a toggle switch you run it to a low manifold vacuum switch….then a brake pedal switch…..in series….before you get to the transmission. the part numbers on these components i believe are a Low-vacuum switch – GM #14014519 and Normally open brake cancel switch – GM #25524845 .

 the low-vac switch so the converter will unlock in low vacuum situations, such as going up hill and heavy throttle.  The brake cancel switch unlocks the TCC when the brakes are applied.  Trucks that came stock with 700R4 trannys came with a low-vacuum switch and a brake cancel switch.  The stock low-vac switch didn’t let the TCC unlock soon enough with this mod. the vacuum on the stock switch kicked in at 3.5″, meaning the vacuum has to get real low before it will unlock.  The vacuum switch part number above  kicks in at 7.5″, which will let it unlock sooner giving you a bit better performance. The brake cancel switch on 700R4 equipped trucks also disconnects the cruise control (if equipped) when the brakes are applied

Now to the outside wiring. run the power wire from 12v key on hot through a normally open brake cancel switch.  This switch will allow current flow, only when it is depressed.  The brake pedal depresses the switch, normally, and releases the switch when the brake is applied.  This switch works exactly opposite the brake light switch, whereas the brake light switch allows current, only when the brake pedal is depressed, the cancel switch interrupts current when the brake pedal is depressed, thereby unlocking the torque converter clutch, such as in a panic stop.  The cancel switch is mounted on a bracket under the dash.  The brake pedal arm makes contact with the switch when it is all the way out.  Just so you will know, most of the time the brake cancel switch is also a cancel switch for the cruise control, if you have cruise.  This is why it is called a cancel switch, it cancels power when the pedal is pressed.  You need to make sure that when the brake pedal is all the way out there is power going through, press the pedal and the power is interrupted.

From the brake cancel switch, power is routed through the low-vacuum switch.  use a junkyard donor for the plug if you can as the prongs are close together and can be a pain in the ass. you can probably find most of these parts in a junkyard if you look in the right spot.  If you can’t find a plug, you can either use some slim female spade connectors or solder the wires on.  Mount the low-vac switch on the firewall or at the very least away fro mthe engine a bit.  Then connect to the new single-pin connector at the transmission .

 

you have pretty much just made yourself 120$ lock up wiring kit for a fraction of the cost. enjoy!