Monthly Archives: June 2011

GM 4L80E layout of components

well, i have also been doing some research into the 4L80E, which is the later 4 speed computer controlled version of the TH400 starting around 1992 to present. i ran across a forum where another gentleman had done a disassembly and pictoral layout of the internals on one of these trannys. i copied it to help me during disassembly and to be honest thought it was pretty good cause it’s an actual picture not a drawing.  i copied it and posted it to my blog. due to the format of my blog, you may have to copy the pictures to your computer and blow them up to read the numbers.   i give credit to whoever put this on an open mechanic’s forum i ran across on the internet.  BTW, i did check my service manuals and the labelling on the components is correct. 



Number listing for rotating assembly 4l80e

4: complete pump body assembly
504: 502: housing assembly overrunning clutch and turbine shaft
529: 4th clutch housing
529: 4th clutch
602: forward clutch housing assembly
623:628 direct clutch & forward band
632: intermediate clutch
640: center support
651: reaction drum and carrier assembly
657: rear brake band assembly
661: 662: 668:671:ect:
Carrier output assembly, main shaft, rear rear internal gear, output shaft assembly , ect


Number listing for valve body assembly 4l80e

301: valve body
302: force motor feed filter screen
303: coiled spring pin
304: check ball plug
305: .375 diameter check ball
306: 3rd reverse check ball bushing
307: o-ring seal
308: 3>4 shift valve
309: 2>3 & 3>4 shift valve return spring
310: solenoid bolt
311: 2>3 shift solenoid
312: 2>3 shift valve
313: 1>2 shift solenoid
314: 2>3 shift valve
315: 1>2 shift valve return spring
316: shift solenoid feed plug
317: shift solenoid feed filter
318: low/reverse check ball sleeve
319: manual selector valve
320: variable force motor (can)
321: force motor retaining clamp

322: PWM solenoid retaining clip
323: PWM solenoid assembly
324: TCC regulator apply valve
325: TCC regulator apply valve spring
326: actuator feed valve bore plug
327: actuator feed valve limit spring
328: actuator feed limit valve
329: accumulator valve bore plug
330: accumulator valve spring
331: accumulator valve


Number listing for Accumulator housing assembly 4l80e

49: 4th clutch accumulator piston spring
50: 3rd clutch accumulator piston spring
52: accumulator housing to valve body bolt (Long)
53: accumulator housing to valve body bolt (short)
402: snap ring
404: 1.615 square cut seal
405: 3rd clutch accumulator piston
406: .859 square cut seal


Number listing for pump assembly 4l80e

202: 4L80E pump Body
203: 4L80E Oil Pump
204: Driven pump gear
205: pump drive gear
206: Pump cover
211: coiled spring pins (3 total)
212: converter limit valve bore plug
213: converter limit valve spring
214: converter limit valve
215: spring retainer sleeve
216: TCC enable valve spring
217: TCC enable valve
218: thrust selective washer
220: M8 x 1.25 x 40 mm bolts (5 total)
221: snap ring
222: TCC valve bore plug
223: TCC valve
224: TCC valve spring
225: TCC valve bore plug
226: retaining ring for boost reverse valve bushing
227: reverse boost valve bushing
228: reverse boost valve
229: pressure regulator spring retainer
230: pressure regulator spring
231: pressure regulator valve
232: pressure regulator plug

GM 700R4/4L60 Transmission

well, i tore down a 4L60E and am building a non lockup 700R4. since these transmissions overlap so damn much both in design, upgrades and parts interchange since 1982, i am going to combine both into a general knowledge source to help you out with whatever transmission from this family you may be working on. in my parts books they even list all of them in the same section. so as i add articles, i may seem to be bouncing between the two styles of transmissions….that’s cause i am.

First, i am going to hit on a few basics and some history of this line of light duty overdrive transmissions. Although these are definitely a different breed of transmission than the non lock up th350’s most of us talk about from old iron cars, they are ancestors. you can see a lot of similarities in how they have evolved over the years. To me it all started in the late 60’s when buick and chevy divisions had a demand for a light duty cost effective transmission over the 400 but not a two speed like a power glide. this is where the th350 came into being. during it’s run primarily in the 70’s it underwent several updates, changes, and variations, including a lock up torque converter clutch….or for short a TCC…to add to fuel mileage.

 in the early 80’s with emissions and fuel mileage becomming a major deal GM had a simply approach to it….2.6:1 rear axle gears, more gears in the tranny, and make a smaller engine idle most of the time with a q-jet. in essence robbing peter to pay paul. This is where the 700R4 came into being, as well as the 200R4 (which was a spin off of the th200 metric trannys). where the th350 had a 2.52:1 ratio in first gear the 700r4 had a 3.06:1 in first gear/1.61 in 2nd, 1:1 in 3rd, and an overdrive of 1:.70,  or 4th gear. they also incorporate a TCC, as do pretty much all modern transmissions to date.

I may have blogged about this previously, but the TCC is basically an internal clutch that is applied by fluid pressure in the torque converter to lock the converter solid so there is no give in the converter.  on the 700R trannys some units would start hitting this as early as 2nd gear but most of the time it was programmed to hit it in either third or 4th gear to improve mileage. When a tcc gets fouled up….it will give you that tell tale jerking sensation at cruising speed going down the road. or better yet when you pull up to the stoplight it kills the engine cause it locks the engine solid to the trannys. when that happens you basically start it in neutral and drop it into gear like an idiot teenager trying to get out of the intersection or you abandon it at the light in the turn lane pissing everyone off within a 1/4 mile and call the wrecker.  yeah….been there done that…..towing the old man’s boat to boot!

if you hear about a 700R4 and or a 4L60, they are actually the same thing. 4L60 is the modern designation of the 700R4 the same way a th400 is referred to as a 3L80. where an older tranny like a 400 or 350 would have both a modulator valve and a governor to control shift points, the 700R’s used a cable in place of a modulator valve. now this is not to be confused with the cable used on a th350- on the th350 the cable was simply used for forced downshift(passing gear). on the 700R4 and 200R4…..and most overdrive trannys through the 80’s…..the cable controlled a throttle valve and was used to regulate low speed pressure and timing to the shift valves directly off the throttle position rather than using engine vacuum. although this is more accurate and in a sense kills 2 birds with one stone, it now makes it much more interesting to change a carburetor from one brand to another. the position of the cable to the center of the throttle shaft is critical so the pressure and timing of shift at cruising and part throttle speed is accurate otherwise it can be an unpleasant experience outside of wide open throttle. 

The older style 700R4/4L60 trannys underwent  several upgrades during the 80’s to resolv7004casee several problems including faulty throttle valves and weak input shafts. there were numerous upgrades and i will detail them in more detail in later articles as i get further into my build. starting in 1987 they had most of the bugs worked out of them. in the picture here to the left is an example of how to identify one of these 700R cores. on the passenger side, the casting has what pretty much looks like a camshaft lobe casting mark over the servo boss. in the picture,i circled it and put a red arrow to it. when you are starting out to rebuild a unit and don’t have a core, this is what you shop for at the yard, and an easy way to spot the right one.

 you time and money purchasing and chasing down upgraded components by going with the newer one, however if you can’t find one or the one you got already is not a newer one: don’t worry- it’s not that big of a deal!  upgraded later 700R4 parts  and numerous update parts and kits are available aftermarket and are a must for any serious built you want to last.

TH700-R4_1now after you find the model you want and the generation you got- you need to know the exact year too. yeapers- numerous valve body mid plates-accumulators-springs- yeah you get the point. it can get down to different models for the same year. if you are lucky you may still have the tag on the top of the housing with a bar code- otherwise above the oil pan to the right rear is a number you need. here is a chart i found that explains it pretty simple on how to figure out what you got.

For me i ended up with a 1988 vintage unit-2 wheel drive. i have already torn it down and will be doing a full pictoral and description of the upgrades i will be doing in future articles. these  are a very popular choice for street rods these days not only for mileage of having an overdrive gear, but the higher first gear ratio.  i will also be converting this to a non-lockup transmission and omitting the lock up clutch. i plan on using this in a non-computer controlled engine application: this leaves me with two options- i would either have to buy an extra kit to control the clutch lock up or literally wire up a toggle switch to lock up the converter.  i elected to just omit it during the build using an aftermarket kit and save a big pain in the ass at the sacrifice of a bit of mileage.

Chrysler A618/torqueflite

So one of my friends here in town decided to go truck pulling and hit me up for some transmission advise and service. sounded like fun so i am game. well, the first thing anyone should do when getting into new projects is to do some research so you have some fucking clue what the hell to look for and what you are working with upon innitial disassembly.

Back in trade school, we had to disassemble/reassemble a chrysler 777 tranny as part of a rebuild class. to be honest that was about the only time i spend on a chrysler production tranny for several years. hell i am an oldsmobile guy . back 8 years ago i teamed with my friends at bottom bulb racing to chassis and fab up a 71 duster for bracket racing that is still running today. this is where i got into the chrysler stuff again and along with it: the torqueflite 727. these are a very popular drag race and motor sports tranny. i have gotten into a few of these in recent years but there simply isn’t the demand for them like the GM transmissions.

Unlike the gm transmissions that have two or 3 major lines/designs of transmissions that changed over the years, chrysler pretty much based all their trannys off the same initial concept torqueflite tranny that debuted in 1956. to look at all the variations would be like looking at the family tree of my great great grandfather from sweden who had 14 kids-who all had 14 kids-who had…..well you get the point. inherantly all the chrysler trannys from the one in my dodge dakota-to the one behind the cummins-to a 904 from the late 70’s-to a 727 from 1969 all share some similar characteristics: and all of em have undergone numerous design improvements and changes.

The A618, later 47RH (hydraulic controlled governor pressure) and 47RE (electronic controlled governor pressure), is a heavier-duty version of A518. It was used in trucks and vans starting in the mid-1990s. While currently used with some internal changes when coupled to the 5.9 L Cummins Turbo-Diesel and the 8.0 L V-10 applications, it’s still a 727 with overdrive and stronger internal parts. It has an input torque rating of 450 lb·ft (610 N·m).

Gear ratios:

1 2 3 4 R
2.45 1.45 1.00 0.69 2.21


95 and earlier trannies (designated –rh)

The earliest version of the RH trans did not have a lockup converter. In 94 a lockup converter was introduced to the RH. Even though the RH is designated H, overdrive (and when present TC lockup) use solenoid(s) to turn on and off hydraulic fluid pressure to actuate these functions. These functions are controlled in an on-off electrical manner in a RH tranny.

The 94 up trans with lock-up has a place in the trans for the lockup solenoid and has fluid passages that do not exist in the earlier non-locking 74RH. A problem with these on the diesel applications is the converter clutches in the 47RH will not handle high throttle or engine braking.

96-up trannies (designated –re)

Were also not true electronic trannies, in that 1-2-3- shifts are still hydraulic controlled. They DID however – rather than use a cable to set throttle position control like they did in the –rh trannies – decide to use a PWM (pulse width modulated – a sort of digital control signal) to operate a pressure control solenoid in the valve body. This is not simply an on-off solenoid, it controls a variable pressure and REQUIRES a PWM driver to control it.

So at this point we are dealing with a 95 year truck with a modified 5.9L cummins…..with a shitload of boost. so i next need to establish if i have the original tranny or not in this truck, then find the appropriate core to begin with to make life A LOT easier for the rebuilder-yours truly. this should be a fun side project so stay tuned!