This site consists of a compilation of public information available on the internet. Disposable paper towels are actually good for this, since they tend to leave very little lint behind, and any lint which does remain is soft, non-abrasive, and is easily trapped by the filter. Shim washers are typically placed behind the thrust bearing on the input drum before the reverse input clutch and drum are installed. Rotating the input drum to help align the clutches makes the task possible, and up to seven plates on a stock clutch you should have counted them need to be aligned to allow full engagement. If the dimension is below 1. Inspect the slew ring and springs closely there are two concentric springs for damage or distortion.
It was first introduced in the 2007 model year in several different models. Anyone undertaking a transmission repair is strongly urged to acquire a thorough repair manual and review it fully. Install the thrust washer on the rear face of the pump housing and retain it in place with TransGel or Vaseline. This method required more than 32 hours, not counting chasing parts and supplies. Click for larger image Install the input drum assembly onto the input planetary gear set and reaction sun shell. Install the reaction sun gear and transmission output shaft. The 8L90 utilizes an off axis chain drive pump to maintain fluid volume and operating pressures.
The separator plate should also be inspected closely where the check balls seal. Later factory versions and aftermarket heavy duty kits provide up to nine clutch plates and steels, greatly improving the holding capacity of the clutch assembly. The orientation is self explanatory if you observe the bolt pattern. If that is why you are reading this, it's likely your transmission has slipped a hub on reaction sun shell. There should be between 0.
Note: There have been many engineering changes in this transmission since its introduction. Assemble rear input planetary set, sprag clutch, support plate, and large lock ring in reverse order of disassembly. In preparation for installation into the vehicle, it would also be good to clean the cross member, lines, and vehicle wiring harness. It is merely anecdotal information presented to clarify the procedures and directions found in published manuals and instructions. Press or drive a new pump bushing into the housing with a suitable tool. Install the single loose upper check ball and accumulator spring, and check that the caged check ball is still in the proper location. Inspect the forward sprag clutch.
Remove the lock ring for the reverse input clutch, then the backing plate, clutch plates and steels. Check and rectify this before proceeding further. We use the most popular pdf document viewer called. Applying antiseize compound to engine fasteners, chassis and mount bolts, exhaust studs, and other various fasteners is always prudent. Closely inspect the splines in all locations, specifically the reaction sun shell hub and mating reaction sun gear spline, the reaction carrier hub spline, input sun gear, and the 1-2 planetary ring gear carrier hub. This information is not intended to supplant or supercede that which is published in commonly available service manuals. Needless to say, I wouldn't be very profitable this way, but a learning experience is almost always worth the journey.
Assemble the low-reverse support plate and clutch stack on a flat surface and check the overall thickness of the stack at its extreme outer edge. Replace seals and wipers as necessary before assembly. A magnetic pick-up tool will be useful. Assemble the 3-4 clutch and supports in reverse order of disassembly. Any signs of damage or cracking in the carriers should indicate a need for replacement. Lightly lubricate the pump rotor and vane support rings, and pack the pump cavity with TransGel or Vaseline to insure fluid pickup once the transmission starts to operate.
Remove the 3-4 clutch steels and plates, apply plate, and retainer, being careful to maintain their order as removed. Replace any parts as necessary. Install the upper separator plate gasket and plate. At a minimum, the existing forward sprag should be disassembled and inspected closely for roller and race damage. Repeated operation of the checks will cause the balls to actually pein the openings in the stamped steel plate until the holes are distorted and enlarged.
Assemble and install the 2-4 servo from the outside of the transmission housing, making certain the clamp pin engages the band. When installed with the support plate and lock ring, the total clearance of the stack should be between 0. 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. Any clutch plates installed new or after solvent cleaning must be soaked in clean transmission oil before assembly. You will need a good supply of towels, rags, or wipes to clean and dry parts. They can also be used under the vehicle to absorb drips and leakage without creating harmful dust. Lift out the vane backing rings and pump rotor and inspect for scoring on either face.
If you have an assistant, you may be able to wrestle the transmission out without a jack, but it is far safer and easier with an appropriate jack. If it has not already been done, drain the torque converter completely. Install the tailshaft housing and seal the end with a suitable cap. Inspect the reverse clutch spring pack and springs for damage, distortion, or breakage. When installed correctly, the converter should slide all the way back to the point where it contacts the adapter bell. The steels for the overrunning clutch should be 0.
Tighten the two M6 X 35 and one M6 X 65 hex cap screws for the accumulator to the same torque specification. Covers transaxle assembly, dis-assembly, diagnosis and troubleshooting Note: There have been many engineering changes in this transmission since its introduction. Install the reverse input drum by aligning the clutch plates and rotating the drum as necessary to engage all the plates on the inner hub, as well as the outer fingers into the reaction sun shell. Remove the forward sprag clutch as an assembly. The pump housing will only orient one way, since there is only one area of the pump which has two bolts close together. It should rotate with some amount of light resistance in the clockwise direction, and not rotate in the counterclockwise direction at all.