In every situation possible, text describes component operation during the apply and release cycle as well as situations where it has no effect at all. Probably best used as a core for a reman. I read somewhere that the Overhaul kit comes with new sealing rings for these pressure switches. Covers transaxle assembly, dis-assembly, diagnosis and troubleshooting Note: There have been many engineering changes in this transmission since its introduction. I'll get more pics of these parts as I inspect them, but here's what it looks like after these are out: If that roll pin falls out, then this pinion:Is free to sling out of the diff carrier and bust your extension housing. I did not do this rebuild, I found the information to do this and wanted to let everyone know how to do this. It's also crucial not to nick or cut the seals; in some cases, I temporarily wrapped shafts in electrical tape while sliding on the seals to avoid running seals over grooves or sharp edges.
Cracked open the filter with a hammer and chisel:Only some fine clutch mud, no metal particles. This tome walks you through procedures like using the J-34094-A tool in order to set the height of the middle thermo element pin right and showing you where the filter pin fits into your productions. Although this information is available in current model year Service Manuals, its inclusion provides for a quick reference guide that is useful to the technician. This is apparently pretty common on factory 4th clutches. Note: There have been many engineering changes in this transmission since its introduction.
. The 8L90 utilizes an off axis chain drive pump to maintain fluid volume and operating pressures. Transmission Manifold Fluid Pressure Switch:This funky thing has 6 separate pressure switches. The opposite side of the half page contains the narrative description of the hydraulic fluid as it applies components or shifts valves in the system. Operational theories of the mechanical, hydraulic and electrical components are presented in a sequential and functional order to better explain their operation as part of the system. Note: There have been many engineering changes in this transmission since its introduction.
Fold-out pages containing fluid flow schematics and two dimensional illustrations of major components graphically display hydraulic circuits. Transmission Range Switch: This is the one that sits on top of the trans case, right where the shifter cable attaches. I will credit that to my awesome cardboard box and ziploc bag organizational system. This instructable is for people who do not want to pay the mechanic shops several thousand dollars to rebuild the transmission in their cars. This is a fix to the problem the Author had when he needed to have this tool to have more length. For clarity this manual will address the disassembly and assembly procedures for the 8L90 and is intended for use by the professional technician. I've now inspected everything I can at least until the sprag retaining ring arrives.
The differences in the design will also leave you stuck somewhere in the middle of your rebuild and in need of a new transmission. I'm guessing some gunk clutch mud? It is crucial to get these lip seals seated properly, so that they sit in the groove with the lip sticking out all the way around. To give credit where credit is due please go to And thank member agrazela for his mechanical know how. Alternatively, sometimes the spider gears sieze to or wear down the pinion and the gears or pinion itself breaks. This manual is a companion manual to the 4T65-E Blue assembly and disassembly manual and is most helpful during a rebuild. The Master kit will have new Borg Warner 3rd clutches. It is also all-wheel drive capable.
Pan Gasket in excellent shape after cleaning, and can be reused. Regulator valve looks good and the bore is fine. However, words commonly associated with the specific transaxle or transmission function have been defined in a Glossary rather than within the text of this book. Three planetary gear sets provide the six forward gear ratios and reverse. It also uses a four element lockup torque converter, four planetary gear sets as well as five multiple disc and one mechanical clutch set.
After I get new piston seals out of an Overhaul kit, I'll probably swap this unit in it's entirety into the current trans and swap in the current trans' unit with Thrasher shift kit already installed. Had a W-body specific mount bolted to it, will probably give away or sell mount. The transmission in this manual was disassembled and reassembled without all factory tools, if all factory tools are used, the transmission would be assembled differently than shown in this manual. Speed Sensor Reluctor wheel:The pins are good and tight. If you have some basic and specialty tools that can be easily bought , then you can rebuild your transmission yourself and save a few thousand dollars.
The transfer of torque from the engine through the transaxle is graphically displayed on a full page while a narrative description is provided on a facing half page. All the roller bearings, roller thrust bearings, and selective washers are fine. I also discovered I can invert the the old 2nd clutch piston and use it to distribute the force of the tool to depress the new spring assembly without bending it, and have room to push the retaining ring back into place. This book has 120 pages of detailed information about individual model ratios, oil passage identification, diagnostic trouble codes, transaxle end play measurements, line pressure checks and a range of component rebuilds, including drive sprocket, case cover and accumulator housing assembly. So I'm likely going to send the hub and the shaft in to Dave at tripleedgeperformance.
However, this book is not intended to be a substitute for other General Motors service publications that are normally used on the job. These pumps seem to be worn similarly otherwise. Since there is a wide range of repair procedures and technical specifications specific to certain vehicles and transaxle models, the proper service publication must be referred to when servicing the Hydra-matic 4T65-E transaxle. All these clutches and steels will come with the Master Kit. It consists primarily of a four element torque converter, three planetary gear sets, five clutch packs, one mechanical one-way clutch and a hydraulic pressurization and control system.