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.

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