i-350 L5-3.5L (2006)
Seals and Gaskets: By Symptom
Technical Service Bulletin # SB06-05-S003
Date: 060907
A/T - 4L60-E Fluid Leak From Pump/Bell Housing Area
TSB SB06-05-S003
4L60-E Automatic Transmission Fluid Leak From Oil Pump Or Bell Housing Area
ISSUE DATE: SEPTEMBER 2006
Affected Vehicles
2006 Isuzu Ascender (US/UT)
2006 Isuzu i-280/i-350 (TI) with Automatic Transmission
Service Information
Condition:
Some customers may comment on an automatic transmission fluid leak. Upon further investigation, the technician may find fluid leaking from the oil
pump or bell housing area. This leak may be very slight with only dampness of one or two drops of ATF observed at the bottom of the bellhousing.
Possible Cause:
Investigation of 2006 transmissions has shown small scratches or cuts in the torque converter hub-to-pump seal. These scratches or cuts may be caused
by small burrs on the torque converter hub, pump drive slots.
Correction:
Remove burrs on torque converter hub, pump drive slots, replace torque converter hub-to-oil pump seal assembly.
Service Procedure
Verify that the leak is coming from the oil pump or bell housing area by using oil dye in the transmission. Refer to Fluid Leak Diagnosis in the Service
Manual for further information. Clean the transmission suspected area of all residual oil and drive the vehicle to see if the dye begins to appear. If this is
a vehicle with very low mileage and it appears to have a small leak, it could have assembly oil in the bell housing which is not truly a leak.
Once the dye has started to appear, disassemble and inspect for small cuts in the torque converter hub-to-oil pump seal assembly. The cuts may be caused
by small burrs on the torque converter hub, oil pump drive slots. The burrs can be seen or felt with your finger and if found, the burrs should be removed
with a file. Refer to (1) in the photo. Also replace the oil pump seal assembly. Do not replace the torque converter for this concern. The torque converter
hub-to-oil pump seal assembly leak caused by these cuts is typically very small, causing only a few drops of fluid loss.
Parts Information
